Car suddenly died, no faults, help w scan please

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Car suddenly died, no faults, help w scan please

Postby TorqueHorse » Tue 01.10.2024, 16:17

Hey folks,
As the title says I was in the middle of a drive and the engine suddenly stopped and won't restart.
Its been a couple days, so everything has cooled off and I still can't get it to start.
I did the paperclip test and elanscan (file attached) and both showed no error codes.

The starter works and the engine turns over, and if I pump the gas pedal it will catch combustion for a little bit, but will never get to an idle and if I stop pumping (or give it too much) the engine just stops. I can smell the rich exhaust gas after those attempts, hear the fuel pump at powerup, and the injectors click (and my fuel gauge says half tank).
This morning I replaced the whole CAS, because that was an easy place to start since I had a spare, but exact same symptoms persist.

I'm not the best at deciphering elanscan data, so I'm sharing here in hopes that one of you experts will be able to spot something that looks off. For the scan, I just had it sitting for a few seconds to make sure I was getting a good data read, then I slowly pushed down the gas pedal to verify the TPS was sending a signal (it matched what I was doing), and then I tried starting the car. I think I tried two times. The first time it caught for like half a second and the next time, nothing.
The actual conditions outside this morning at the time of the scan were around 27 degrees C, and around 1bar of pressure, and it had been sitting all night.

I'll keep sorting around doing physical checks on all the stuff, but if anyone spots anything in this scan in the meantime, I'd be very appreciative.
Thanks!!!!
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-Matt N
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Re: Car suddenly died, no faults, help w scan please

Postby Tuga2112 » Tue 01.10.2024, 16:24

try disconnecting the MAP see if its any better.

i assume it wont start even then cold is that right ?

what you describe is similar my experience 2 years ago when the fuel line came loose inside the fuel tank (the pump was not pumping into the line, it was just making water move inside the tank) HOWEVER i think its unlikely that be your problem. when that happened to me. it was because i didnt clip the fuel line to the pump well.
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Re: Car suddenly died, no faults, help w scan please

Postby TorqueHorse » Tue 01.10.2024, 17:35

Thanks J,
No change with MAP disconnected :(
-Matt N
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Re: Car suddenly died, no faults, help w scan please

Postby Tuga2112 » Tue 01.10.2024, 17:51

another thing worth trying is starting in diagnostic mode. that will make it ignore some of the sensors. see what happens.

also if you have a timing gun.
put the timing gun around each of the leads and check if it flashes while cranking. that will tell you if the leads are getting power without needing to undo the plugs. (quick unintrusive way to check if the coil packs and control unit are good)
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Re: Car suddenly died, no faults, help w scan please

Postby TorqueHorse » Tue 01.10.2024, 18:22

Thanks :)
Won't start, even with paperclip. Waiting for sun to get out of the way, then I'll start doing physical checks.
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Re: Car suddenly died, no faults, help w scan please

Postby Simon_P » Tue 01.10.2024, 22:26

After a quick glance at the scan, nothing obviously wrong.
When it's this basic it's spark or fuel. The ECU measures the signal but not if there was a spark or fuel injected.
The gauge says half but have you got any? The float can get stuck on the vent pipe.
Are you getting a spark when cranking ?
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Re: Car suddenly died, no faults, help w scan please

Postby TorqueHorse » Wed 02.10.2024, 01:47

Simon_P wrote:After a quick glance at the scan, nothing obviously wrong.
When it's this basic it's spark or fuel. The ECU measures the signal but not if there was a spark or fuel injected.
The gauge says half but have you got any? The float can get stuck on the vent pipe.
Are you getting a spark when cranking ?


Thanks for looking and the suggestions!

Yes, the current thought is lack of fuel.
The spark plugs are getting spark, and the injectors are getting signals (used noid lights to confirm signal and the "click" test to confirm each injector was happy).
We took off the return line from at the top of the gas tank and nothing was coming back. I even put a hand vacuum hose on the FPR and it would hold vacuum, but nothing came back after running the fuel pump multiple times.

Tomorrow I'll check the fuel supply lines.
Current thinking is maybe the autocross I ran the day before, plus all the "drive it like you stole it" I'd been doing all weekend and having just gone up a really big incline finally shook something free that is blocking fuel delivery somewhere.
TY!
-Matt N
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Re: Car suddenly died, no faults, help w scan please

Postby alan e » Wed 02.10.2024, 08:06

To check if its fuel just spray some easy start or even brake cleaner into the air intake if it starts its fuel if don't start its spark.
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Re: Car suddenly died, no faults, help w scan please

Postby TorqueHorse » Fri 11.10.2024, 16:00

Finally found out what the problem was.
Thanks Alan for that tip. I should have trusted the results, but thought I was doing it wrong, and had sprayed too much or too little. So I ended up calling in the parts cannon because I wasn't trusting what the tests were saying: Good spark at each cylinder; fuel flowing and injectors OK and getting good signal!!!???. It didn't make sense...and instead of going down complex rabbit holes, I should have started at the basics!

No compression. :oops: :o :roll: I managed to pop 3 cylinders in one go. :twisted: At least I was having fun at the time.

Oil and coolant look fine, so that dissuaded me from starting there, but its such an easy test, future me should always start there. Anyways, I was planning to pull the engine before next spring anyways, so now I'll just get a jump on things. And maybe an excuse to upgrade some stuff while I'm in there. :)

Thanks all (online and offline) for the help over the past couple weeks in trying to chase this down.
-Matt N
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Re: Car suddenly died, no faults, help w scan please

Postby Tuga2112 » Fri 11.10.2024, 18:05

TorqueHorse wrote: I managed to pop 3 cylinders in one go.


i recall you mentioned before you never really got it properly working. is this just an extent to that ?
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Re: Car suddenly died, no faults, help w scan please

Postby TorqueHorse » Fri 11.10.2024, 19:59

It's been burning a bit of oil, but I think that is because the rings aren't making a good seal.Oother than that, she had been behaving recently. Temps always looked good. Just did a leak down test and it seems #2 cylinder blows into both 1 and 3 now. No air leaks anywhere else really. So this indicates a failure at the head gasket area (and/or a warping?). But I'll look over everything again when I get it apart.
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Re: Car suddenly died, no faults, help w scan please

Postby alan e » Sat 12.10.2024, 08:57

May be worth checking the cam belt not moved and the timing is ok if the valves are not closing at the right time when the piston in coming up you won't get compression.
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