Off to work.

My office was as beige as it ever was, the 90s aura was not everyone’s favorite, particularly on such a sunny day, but I liked it.

Paperwork was the name of the game that week. A few functional improvements for the shift quality of our 9-speed transmission for the Jeep Compass had been developed and their validation was almost done. A software or calibration change that makes it to a production plant has to go through a long list of tests, checks and approvals.

An engineering Change Document (CN) is what FCA used to call these approval documents, and it was my responsibility to carry it through the required steps.

Dull, is what many engineers would call the task of creating, managing and finalizing a CN. Honestly, I liked it. First, it is a very straightforward and sequential process: you document the change, take it to a meeting with managers and executives to kick off the work – initial approval – and work on documenting the validation efforts as they happen. Different people approve the document once all validation has been completed, and the software is then good to go to the plant. Boring sometimes, but very satisfactory.

My workload had been very high during the winter, but it was now more manageable, so when the email came in, I was happy to offer my help.

Miguel,

Marco is coming from Italy to check on a 2018 MP 1.4L that keeps setting a P0805 on the ECM. The vehicle is a Roush fleet asset, it’s in the Auburn Hills Roush facility. Vehicle Scan Report is attached. Have you seen this issue before? Any help is greatly appreciated.

“What the hell is a P0805?” I thought and immediately logged on to our service website to investigate. I knew it was a DTC (Diagnostic Trouble Code), but I had no idea what it was supposed to mean.

“Clutch position sensor A Circuit Malfunction” was the description, which made sense since the Vehicle Scan Report showed the vehicle had a manual transmission.

Basically, the diagnostic makes sure the clutch position sensor detects a pedal press every time the engine speed changes at a given vehicle speed. In other words, the controls were designed to expect a clutch pedal press every time the driver shifted gears.

My Italian colleagues were responsible for the engine controls for the Jeep Compass (MP is its internal code) 1.4L Turbo, but I was responsible for documentation, release to plant and vehicle integration of this engine, since the Compass was built in North America, where I was based. This meant that when there were issues at a vehicle level, I was expected to lead the investigation. In this particular case, though, I wasn’t made aware of the problem and they decided to fly someone in from Europe to investigate.

My mood was still great. The clock read 10 am, and I was outside, windows down, sunroof open, and my car enjoyable as ever. I was on my way to Roush to meet Marco.

Very friendly and approachable, Marco shook my hand and we chatted for a few minutes before walking in to the main lobby. I followed him inside and noticed his outfit was very… Italian. Business casual would have been an understatement; he looked like a real estate agent from Milano.

“My friend,” he said while addressing the guy at the front desk.

“I am looking for a vehicle, a Jeep Compass, that is setting a clutch pedal fault code. Here’s the VIN.”

The young dude at the front desk checked his computer and told us the vehicle was in the back and handed us keys to it. Before heading out to the car, though, I had a few questions.

“Hey man, a few questions maybe you can help me with,” I told the young man.

“Is this vehicle driven by the same driver all the time? Like, exclusively?” I asked.

“No, drivers have a schedule so vehicles rotate from one to another,” he responded.

“How many 1.4L manual transmission Compass do you guys have in the fleet?”

“Just this one here, but Las Vegas has around 5.”

“Has any of those 5 vehicles ever set this fault code?”

“No, only this one.”

“Is any of the drivers a very experienced truck driver? Someone that might have driven semi-trucks in the 70s or 80s maybe?”

“The driver that reported the issue might have that experience, yes, he is one of our most experienced drivers.”

That was a very interesting clue.

You see, in older heavy trucks, transmissions were not synchronized. When shifting from one gear to another, the speed of the engine changes in relation to the speed of the wheels. Say you shift from 2nd gear at 2000 engine rpm at 40 MPH, 3rd gear, at the same vehicle speed, will mean a lower engine speed, say 1500 rpm.

Without synchronizers, gears would grind when shifting: gears were spinning at 2000 rpm and all of a sudden, you want to engage them with gears spinning at 1500 rpm (slower). That won’t work.

What you do is you pull the shift lever to Neutral, leave it there until the engine goes from 2000 rpm to 1500 rpm, and then push the shift lever into 3rd gear. This can be done without using the clutch pedal.

Modern transmissions are synchronized and you don’t need to wait until the engine speed matches that of the next gear: an internal mechanism slows down the gears so their speed matches and the gear shift lever clicks into position without problems. You can, however, use a synchronized transmission just like you would an older non-synchronized one.

Man, I don’t know if it was my mood that day or what, but I was certain that this issue was really a driver shifting without using the clutch pedal. This is totally fine and expected. I do it all the time, and so do many others.

Were the controls designed by someone who had never heard of this before? Couldn’t possibly be.

I shared my theory with Marco and he immediately said that it was not possible, that such a maneuver would heavily damage the drivetrain.

“I do it all the time in my own car,” I told him, confused by his reaction.

“Maybe you should have your transmission inspected, then.” I detected sarcasm.

We jumped in the car and I connected my diagnostic tools. My laptop confirmed the fault code had been cleared and I gave it to Marco so he could monitor for codes while I drove.

About 15 minutes later, the screen of my laptop showed the magic combination of alpha-numerical characters that I was so excited to see: P0805 – Clutch Position Sensor A Circuit Malfunction – Active.

“There it is. It is a false failure most likely; we will have to send this sensor to our supplier to analyze it,” Marco said.

“What makes you think that?” I challenged him.

“I am looking at the screen and every time you shift, the counter of events (clutchless shifts) increases.”

“Yes, I’ve been shifting without touching the clutch pedal all this time,” I said, proudly.

“Haha, I would have felt and heard if that was the case!”

A quick demonstration, both up and downshifts, and he was now convinced.

Someone who had never heard of non-synchronized transmissions and how they worked had indeed designed these controls and diagnostics.

Gotta love spring, man.

Press clutch to shift gears – a story

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Parts arrive just days before they’re needed. Logistics operate like a living organism. Every vehicle can be built with dozens of combinations. In some plants, multiple models share the same line. The order in which parts are assembled is the result of relentless analysis and testing, all in the name of efficiency.

Engineers work day and night to keep production running. A single minute of unplanned stoppage can mean thousands — sometimes millions — of dollars lost. The automotive industry makes money by building cars fast and cheap at scale. There’s a reason the United States was able to outproduce its enemies during the Second World War. Industrial capacity matters. And much of that capacity was born in automotive plants.

My experience inside a plant, though, was limited — very niche. Throughout my career, I had worked in software and calibration of powertrain modules. In other words, the code that controls engines, transmissions, electric motors. My world lived inside ECUs and CAN messages.

Because of that, my experience centered around a part of the process that many of us quietly fear:

End of Line.

The line never stops for you.

It stops because of you.

And that’s a place no one wants to be.

But those who have been there — who have felt that weight — gain something others don’t. Because when it happens, you enter a strange dimension. Time stretches and compresses at the same time. Sounds distort. Hunger disappears. The constant buzzing, whirring, and shouting of the plant turns into background static. You stop being a person. You become part of the machine.

It started for me on a Friday morning.

It was cold. Walking out of my apartment complex off 12 Mile Road in Southfield, the pavement was dark and icy. It was January. I was in my third week at FCA.

Every morning I woke up excited. Years of hard work had finally earned me a childhood dream: working for an OEM in the Motor City.

I was learning what a Release and Integration engineer in Powertrain Controls actually does — connecting CAN tools, using proprietary diagnostic software, completing DVPs, performing on-board end-of-line tests. My supervisor would teach me the basics, hand me harnesses and guides, and send me into one of the many engineering parking lots to find a test vehicle.

I didn’t have an assigned project yet. No external pressure. My mornings were filled with learning — old Word documents, printed booklets, conversations with engineers who had been doing this longer than I had been driving.

Motivation was through the roof. I was there to learn everything.

During a group meeting in one of the corporate conference rooms across the mall-looking campus, my manager proudly announced that we were about to begin full production of a new product: the 2017 Jeep Compass.

It was going to be a volume seller. Competitive price point. On- and off-road variants. Built in Toluca, Mexico. There was just one problem. The engineer responsible for the program had just moved to another role. He wouldn’t be at the plant to support the launch. At the end of the meeting, my manager paused. He looked worried. Then he looked at me.

“Miguel, you speak Spanish?” he asked in his thick, Russian-like accent — which I later learned was actually Syrian.

“I do, sir.”

“You been to Mexico?”

“I’m Mexican, sir. I’ve been there.”

“Ok. Get a credit card and book flights. I need you at the plant Monday morning.”

“Yes, sir.”

On the outside, I looked calm.

On the inside, I was panicking.

I didn’t even fully understand what my job was yet. I had never booked corporate travel. I had never traveled alone for work. I didn’t know what was expected of me at the plant.

Now I was under pressure.

Sunday morning came fast. I showered, grabbed my bag, and stepped into a foggy, dark, melancholic morning. I started my trusty orange Civic Si — my partner for years — and drove toward the airport.

I cried on the way there.

I was excited. Nervous. Overwhelmed. It felt like I was growing up in real time. Like doors were opening that not everyone gets to walk through. I was grateful — and terrified.

At the plant, I immediately connected with the local engineers and technicians. The hotel was a few blocks away, with a daily shuttle back and forth. The polished concrete floors of the End of Line area shined under bright lights. The smell of assembly grease burning off during first engine start was unforgettable. Technicians in steel-toed boots, white hard hats, yellow vests. Rugged tablets mounted to steering wheels. Cars creeping forward. Controlled chaos.

I loved it.

My first task was a plant tour. My resident engineer, Óscar — a very white Mexican who looked American and spoke English with the most stereotypical Mexican accent — introduced me to the key players.

I saw the whole process: from Body in White to final, where the last electrical tests are performed before Rolls and Alignment. Knowing the local language helped. I made friends. I was learning.

The first vehicles I inspected were the last pilots built before production. Pilots are vehicles used to validate systems and plant processes before customer builds begin.

Two of them had set DTCs — Diagnostic Trouble Codes — so they couldn’t be shipped yet. Another engineer was already looking into it, but I stayed to help.

It was simple. Old software. Quick update. Problem solved.

My first day flew by. Everything seemed smooth.

The next morning, as soon as I walked into End of Line, someone approached me.

“Hey, are you the powertrain guy?”

“Am I?” I thought.

“Yes. I’m from powertrain.”

“Ok. Come with me. Óscar wants to talk to you.”

Óscar looked exhausted. The night before, I had left at 8 p.m. He was still there. It was now 7 a.m., and he was already back.

“He needs to relax,” I thought.

I had no idea what was coming.

“Did you guys make any change to the transmission software for Job 1?”

“I don’t know,” I said.

He took that as an insult.

“So, you’re telling me you don’t know what we’re flashing into these cars at Job 1?”

He was getting upset.

I didn’t even know what Job 1 meant. It’s the official start of production — the moment vehicles go straight to dealerships. Everything must be validated. Certified. Approved.

And I had no idea what software was in those cars. What should have been in them. Or how to check. Or even who to ask. The line had stopped because of us.

Trust between Product Development and Manufacturing is fragile. It’s the oil that keeps that complex machinery moving. Without it, something breaks. And what breaks is always quality.

I was called into a meeting with a Quality Engineering Manager who was furious at powertrain — and I was “the Powertrain Guy.”

I’ve never been asked so many questions I couldn’t answer.

Very calmly, I explained the situation and said I would get the answers as soon as I could.

He looked me in the eyes.

“This is not about what you can do. It’s about what you should have done. Fix the problem before 10 a.m.”

Back in the repair area, I jumped into one of the failed vehicles and opened my laptop, connected my CAN tool and opened the diagnostic software.

And then I realized something worse: my tool didn’t have the right hardware.

I had trained on my supervisor’s setup. I had been issued my own right before the trip, and now it wasn’t working. Imagine what they’d think if they realized I was useless.

Panic mode.

I messaged my supervisor and tried to look busy. His advice was simple: ask for Óscar’s CAN tool. He clearly didn’t understand the atmosphere here, or so I thought.

As expected, Óscar was furious. From his perspective, the guy flown in from Detroit had no idea how to fix the issue that had just stopped his line.

Winning that trust back would not be easy.

At some point, I stopped thinking about my reputation and just focused. I paid attention.

With Óscar’s CAN tool in hand, I began the real work.

Everything I thought I knew about the diagnostic software suddenly felt weak. Those long Michigan afternoons exploring menus and options meant nothing under pressure. It felt like stress had erased my memory. My superpower became appearing calm. If I looked panicked, they wouldn’t trust me. That would put me under more pressure — and my boss under even more. I wanted to build a name for myself. A good one.

Stress wasn’t going to help me get there.

After a few hours working with my supervisor remotely, I finally connected to the vehicle properly. Investigations like this are the bread and butter of Powertrain Controls engineers, but I didn’t know that yet.

Slowly, the fog lifted. And then I saw it.

The vehicles I had helped update the day before? They had old software. So did the first vehicles off the line this morning. When Job 1 began, someone at the plant uploaded the old file — likely from a local computer — thinking it was the latest version.

They had flashed the old calibration back into production cars.

That was it. It was almost embarrassing how simple it was. The pressure evaporated. I could breathe again.

But solving the technical problem wasn’t the hardest part.

By the time the issue was flagged and the line was stopped, dozens of cars had already been built. They were scattered across the 120 acres of the Toluca Assembly Plant, moving through audits and quality checks.

Someone had to track every single one. Reflash them. Verify them. Make sure none slipped through.

No one better for that job than The Powertrain Guy.

The industrial warehouse where we sat was furnished to resemble a corporate office. Technically, that’s what it was. Desks, chairs, bad lighting, the quiet hum of HVAC fighting a losing battle against winter. For eight hours or more we would sit there, minding our business, responding to emails, calling into meetings.

To most people involved, trips like this were fun, or “okay” at best. A change of scenery. A break from routine. To me, they have always been dreadful.

Driving eight hours north in the dead of winter, just to sit in a warehouse that felt hollow and lonely. That’s what these trips were. The kind of place where time doesn’t move forward so much as it pools.

Eight in the morning and five in the afternoon were the only moments that mattered. Not because of clocking in or out—you never really clock out on trips like these—but because those were the moments when something actually happened.

Around five Ram 1500 trucks sat inside industrial freezers at minus forty degrees Celsius. They waited there, motionless, for eight to twelve hours at a time.

At eight sharp, we walked into the freezers with laptops in hand, wrapped in layers meant to delay—not prevent—the cold. Breathing was uncomfortable. The air was painfully dry, biting, unnatural. The smell of unburnt fuel from attempts past always seemed to linger, as if the room remembered every start, every stall, every crank.

The sight wasn’t comforting either. The space felt smaller than it should have, the walls closer than they looked. There was a subtle sense of panic in that realization.

Now the show began. Laptops plugged in. Freezer doors open to drive the vehicles off.

At the push of a button, the 3.6-liter Pentastar V6 engines turned slower than they normally do. The sound of struggling starter motors filled the air, alongside the loud hum of the freezing equipment,

If our work had been done right, the engines fired immediately, climbing into a high idle—just as high as emissions testing would allow—defiant against the cold. Otherwise, back to the warehouse to look at data and fix our mistakes.

“See you at five.”

Press clutch to shift gears – a story

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“Up you go,” Jamie said, as he sunk his right foot while his left guided the clutch pedal back, very slowly, to its resting position. “No Cigar” by Millencollin was playing through the speakers, loud as it should. The HVAC was blasting cold air still; the engine coolant that should warm up the cabin wasn’t ready to do so just yet. A sudden jolt, a “jerk” if you will, surprised Jamie. “Fuck me,” he muttered under his breath. Brakes. Clutch in. Start button pressed. No luck. Numerous attempts failed and 15 minutes later, the path was clear: tow truck.

Turns out Jamie wasn’t the only one. 4 more cases like this happened on that cold November throughout the country, 2 more also in Pennsylvania.

“Make sure you document software part numbers, build dates and sales codes.” My coach was too excited about my very first problem-solving Green Belt project.

“I’ll send you the ‘IS—IS NOT’ template. Work on it on your own and we can review later,” she said.

I was used to investigations like this one. 3 years in Powertrain Controls had made me quite competent, at least that’s how I felt. “Most likely user error,” I thought to myself as I loaded the email attachment containing information on all reported cases until that moment. You have to understand, this was America in 2019; less people than ever knew how to drive a manual transmission car properly, and it wouldn’t be the first time a customer couldn’t get used to the clutch pedal feel, stalled, and blamed us. Hell, this was so common even among engineers, that I was ready to dismiss the report as a waste of time.

Those 3 cases in Pennsylvania were very interesting to me, though. Why 3 in the same week? These vehicles had been in service for a few months now. No reported dealership visits. All using the same Engine Control Module (ECM) software part number. Similarly equipped and all sold in the same area with a few weeks’ separation. Build dates were close, but not too close; they were not built on the same day or even week.

I can’t remember specific details of the non-Pennsylvania cases; all I know is that weather had also been slightly colder than usual in those places.

The IS—IS NOT exercise wasn’t conclusive. This tool helps the problem solver lay out all known facts about the event being investigated (IS) and contrast them with things that could be true, but are not (IS NOT). “The affected vehicles had manual transmissions (IS), but they could have had 9 or 6-speed automatics (IS NOT). What’s different in manuals that was potentially causing the issue?” This is the question that, when answered, would justify my salary.

By day 3 of the investigation more reported cases were piling up in my email inbox, and my supervisor and I started to realize this wasn’t only user error. Multiple meetings with various other teams yielded nothing useful. “Too many cooks in the kitchen,” I thought. But I had an advantage: my own manual-transmission 2019 Jeep Compass.

Powertrain Triage Engineer was my new official title. I was very proud of having been accepted in such a prestigious organization. Prestigious to me, at least. Most everyone else, inside and outside of the group, thought of it as “just another job.” Nah, not to me. I’ve always been a dreamer, and experience has taught me how to leverage my dreams into motivation. To me, I was now part of an elite engineering unit whose task was to fix critical issues no one else was able to. This was the SEAL Team Six of Powertrain Controls.

Armed with my childish curiosity and my newfound identity, I grabbed my CAN tool and headed out to the parking lot, where my Compass was waiting for me, anxious, excited, curious. Or maybe she was just there, an inanimate object. But that wouldn’t be as fun. Either way, the next couple of hours would be an exercise in patience, focus, and faith. Stall after stall, I had faith that I’d be able to replicate the issue: stall, crank, no start.

“Fuck yeah!” I yelled. Finally: replication. Once. No idea how, and I couldn’t do it again, so I felt frustrated. But for a hot minute there, I thought I’d hit the jackpot. This proved to be a very valuable lesson that shaped my career: do not jump to conclusions.

You see, cold engines in cold weather behave very differently than warm engines in warm weather. This detail I overlooked. At least partially. I was confident that cold weather was playing a role here, but it wasn’t as simple as that. All vehicles are extensively tested at various temperatures, from –40 °C to 55 °C. All kinds of driving maneuvers in extreme conditions and in-between expose engineers to how the systems of a vehicle behave, and corrections are made when needed. This did not look like an oversight.

Most of my testing was done, by definition, on a warm engine. Consecutive starts, stalls, restart; warmed the engine up. Not the first couple of starts, though: the engine was cold as it had been sitting, untouched, for a few hours.

On a gasoline engine, fuel is atomized to improve combustion efficiency. More fuel droplets mean more contact area between the flame and gasoline, so better combustion results. Port-injected engines, like the 2.4L Tigershark on the Jeep Compass, atomize fuel by injecting it on a closed, hot intake valve. It vaporizes just milliseconds before the valve opens, and is then sucked into the cylinder by the vacuum created by the downward motion of the piston. Cold valves do not vaporize fuel so the ECM needs to compensate by injecting considerably more fuel until the engine warms up and proper fuel atomization occurs.

“I can only replicate it in the morning or after work,” I told my coach, “so I know it’s temperature related.”

“What’s next, then?” she asked, challenging me to think harder, more methodically, like the training had taught me.

“Air, fuel, spark,” I replied. Her gaze told me she didn’t know which one to tackle first, and neither did I. But data will always hold the answers.

She is a very jealous, borderline shiesty character, this “data.” Though plural of datum, I envision “data” as a mysterious entity with whom the problem-solving dance takes place. Once you “have” her, you have got to know some moves to read her. Sometimes she takes multiple forms throughout an investigation; maybe one holds the answer, maybe one holds clues and maybe one holds nothing. It’s part of the beauty of problem-solving to learn, eventually, to identify them and seduce them through this dance.

“Air, fuel, spark” is one of those phrases you never forget. Everyone has phrases like this, but not everyone feels a strong connection to them. I do. “Air, fuel, spark” is, in essence, what a gasoline Otto-cycle engine needs to fire, and therefore, produce power. But, like most things in my life, it has a deeper meaning: method, order, control. This phrase reminds me that in most things, we can understand how to solve a problem by observing and analyzing what’s needed for something to occur and contrasting it with what we currently have. The delta between those two scenarios is our answer.

Air was easy to confirm. MAP sensor readings were available and looked normal. Vacuum was present during operation, back to barometric after a stall.

Spark was slightly trickier. Not because of difficulties acquiring data. More so because this wasn’t a binary question. Yes or no was easy; spark was being reported. Was the ECM commanding and actuating spark plugs to fire at the right time? What even is the RIGHT time? I was no specialist, so I decided to rule it out, for now.

Fuel. The fountain of life for combustion engines. This is yet another non-binary question, since confirming the presence of fuel was very easy. You could smell it. This was a key finding. In modern cars, you are not supposed to smell much fuel out of the exhaust, since excess hydrocarbons are regulated by emissions standards. Was it too much fuel injected, or improper combustion?

Stalling a manual transmission car is easy. Not this one. The little 2.4L Tigershark held on for dear life more than any other small engine I’d ever stalled. That wasn’t the case with V8s, for example, those have plenty of torque so you never feel them struggling; they either stall or they don’t, no drama. Older engines don’t have a lot of drama either; they don’t even try to stay alive.

To my keen or obsessive eye, this was strange. I was but a rookie in this industry so I couldn’t tell if such a dramatic struggle to stall a 180-ish horsepower 4-cylinder engine was normal.

Controls engineers are a weird kind, or at least here at FCA, or Fiat-Chrysler Automobiles. They design the control strategy, the “logic” of our control software. “IF the temperature of sensor 1 exceeds a certain value, then turn the fan on!” That kind of logic. Our software is a compendium of interconnected pieces of logic that constantly monitor what’s going on in the real world (inputs) so actuators can be commanded to make changes (outputs). Thus, controls engineers are extremely knowledgeable people, but mostly in their particular area; they are specialists. On the contrary, I was, and still am, a generalist; I hold just enough knowledge of many different areas that I blend, mix and use to solve bigger problems: system-level problems.

I was surprised to know that none of the controls engineers I asked knew if there was a feature in our software to prevent stalls on manual transmission cars. Automatics do have it, but no one seemed capable of confirming its existence for the manual transmission Compass.

A different breed altogether, calibration engineers tend to be more of a specialist-generalist. My calibration engineer was quick to confirm the feature does exist, and he personally calibrated it to dump more fuel in the cylinders when the engine speed falls under a certain threshold with the intent of ‘keeping it alive’. Ah! That explains the “struggle” I felt when trying to stall the engine; more fuel = more torque, at least in this case.

This detail, along with my suspicion of a cold engine being related, led me to the golden egg: replication. Now I had to feed the goose hoping to get more. As you might recall, the issue was not the stall per se, but the inability of the engine to restart after a certain stall. That “certain stall” I had just replicated. So how do I replicate it quickly? Well, my theory was that there was more fuel than needed in the cylinders, so if I had a way of giving the engine air and spark only, I’d be able to confirm my theory: if it fires, we know there was fuel in it already.

Luckily, our software had such a feature built in. Cleverly called “Clear Flood Maneuver,” triggering it would obviously attempt to clear a fuel flood in the cylinders by only allowing spark, but not fuel, into the cylinders. It fired right up and ran for a few seconds, until the gasoline inside was fully burnt. I was ecstatic!

“This is great!” my coach said. “But… what is this telling us? This does not tell me how to fix it.”

She was right. I only proved 2 things: 1) the issue does exist, and 2) it is related to excess fuel in the combustion chamber. Now what? Time to dance again, but this time I did not have a partner; I needed data of the issue happening, which was easy to get.

As one gets closer to the root cause, those dances become easier. More fun at times but less challenging; they feel more familiar since by now, the issue and the physics behind it are better understood, less of a mystery.

Data clearly showed injectors dumping gasoline due to “stall protection,” causing the feeling of the engine struggling to continue running; no surprise there. Upon my first restart attempt, however, something surprising happened: even more fuel was dumped during cranking. Confused at first, I went back to talking to myself. “There’s already a significant amount of fuel in there; why are we adding more?” It made no sense. Remember how cold engines behave? Valves are cold. Gasoline will not be properly atomized. We need more fuel to ensure combustion.

Well, turns out that I was right. Trying the same “stall protection” maneuver on a fully warm engine showed that roughly the same amount of “excess” fuel was being injected in an attempt to prevent a stall when compared to the cold engine data. Since I was able to actually cause a stall, we know that most of that fuel remains inside, unburnt. The difference was that I could very easily restart the engine normally the next time I pressed the START button; no Clear Flood Maneuver needed.

There are moments in life that, in retrospect, or to an external observer, seem mundane, boring. Some of these moments, to those who experience them, can feel enormous, life-changing.

Novels are written around moments like this, history has been shaped by them, the elderly won’t stop talking about them to the young ones, no matter how bored everyone looks when forced to listen to the same boring, seemingly innocent and unimportant stories.

Those data, or “that data,” my final dancing partner of this investigation, froze this moment in my mind. Unimportant as it may look to the uninvolved, looking at colored lines in my screen confirmed that all my sacrifice to get to where I was, finishing school, moving to another country, pushing through all the obstacles, had been worth it: I was really following my passion, not just a job.

“On a fully warm engine, the start fuel multiplier is 1. On a cold engine, this multiplier is 1.3, 30% more fuel injected into an already flooded cylinder makes spark ignition impossible,” I concluded. My results, presented to senior managers and calibration engineers, was convincing and applauded by many.

One of the calibration engineers, though, an old, experienced and particularly grumpy member of the crowd was not happy with my conclusions. It meant more work for him.

“Well, welcome to calibration, I guess,” he said in a very ironic, borderline mocking tone.

To me, that was a compliment. I was finally entering the big leagues.

Press clutch to shift gears – a story

April 15, 2026 No Comments

Cold air, clear skies and sunlight. My morning workout about to start, taste of cherry…

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End of Line – A story

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Ah, the beauty of an assembly plant. Cars roll out by the minute, synchronized with…

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PLAN – Designing an EV conversion from scratch: a SPARK walk through

March 1, 2026 No Comments

Now that we’ve defined what we want this conversion to accomplish, we can start working…

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Cold Trips – a story

February 14, 2026 No Comments

Boring. Dark. Cold. The industrial warehouse where we sat was furnished to resemble a corporate…

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Select – A SPARK walkthrough :Designing an EV conversion from scratch

January 31, 2026 No Comments

Ah, EVs. Magical to some, blasphemous to others. Few topics divide the automotive world quite…

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Stalls – a story

January 15, 2026 No Comments

It was a chilly Pennsylvania morning. Jamie was late to work again; he forgot to…

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