Random stall becoming less random
 

It seems to be temperature related, and when I try to restart it, the gear indicator lights up the "2".

I'll leave the house and around five minutes of driving, the engine shuts off. But not every time. I have to coast to a good spot to pull over and crank, wait, and crank until it starts. It happens again if I go to the indoor golf dome for a couple of hours when I leave. But if I don't stop, I could go on a long trip without it shutting off. Every time, it won't shut off for the rest of a trip.

I have checked and repaired every engine, body, and frame ground. Maybe there is a compromised ground connection inside a wiring harness, but why does it seem to be temperature related? I have verified that I don't lose fuel pressure through HP Tuners scanner, and if it were the fuel pump shutting off, I have tried activating my auxiliary pumps in my surge tank. I will open the throttle all of the way to activate the pumps, let off the throttle and immediately crank it again. That should cause it to fire for at least a split second if the in-tank pump was bad, I replaced it last spring for this problem. I have read about bad ignition switches causing random shut offs, but I don't want to buy one as a guess. I can't do anything else until the snow melts and the Sun comes out.

If it is temperature related, it sure is weird that it happens at a not fully warmed up temperature. Not cold, and not at operating temp. That, and the display indicating second gear until it restarts.

Come on, all of you junior CSI guys, dust my truck for fingerprints. :lol:

If this is a 2000 there is no fuel pressure in HPTuners scanner so I am not sure what you are looking at.

There's a port on the side of the HP Tuner interface that you can add custom inputs, like wide band O2 sensors, fuel pressure gauges, etc.

Ah okay, didn't know you added one.

Um. Yeah, I was also wondering how you were saying fuel pressure was checked through HP Tuners...🤔

Can you post a picture of what you have?

A quick check with a mechanical fuel pressure gauge is easy enough. You are either losing fuel or spark or injector pulse. Swap fuel pump relay.

Blinking on the gear selector is something I've never heard of.

Somehow your neutral safety switch is fucked is what I would think if it flashes second gear.

But the flashing second gear is limp mode I am 99% sure

It could also be the PCM failing if its temp related. Just went through something similar on an E38 ECU on a 07-08

That or a compromised wire for the grounding system. Just beep test all your grounds and make sure there is continuity amongst them all without too much resistance. Grounds heat up with resistance and swell and make contact until they cool off again.

Datalog batter voltage and see what its doing.

Thanks for your answers so far.

The indicator shows second gear when the engine won't start. It's solid not flashing, and stays there regardless of the shifter position.

As far as my electronic fuel pressure sensor goes, picture this: I have an older Magnafuel pressure regulator with four ports. One is the return, two are from the return side of each fuel rail, and the last one is the test port. I have a 0-5 volt 100psi sensor that has the same specs as the AEM. I don't remember if the supply and ground tie into the TPS or the IAC, it's been so long. The third wire goes to the HP Tuners interface, I don't remember which terminal but it is MPVI.2 -> AEM (PN 30-2130-100) 100 PSIg in my scanner channels.

PCM failing sounds logical.

Beep testing the grounds could only be done during the couple of minutes that the engine won't start out on the highway, that's not going to happen. I will argue your point about a ground wire swelling. That would make the engine not start from cold, then not run for a few minutes until the wire swelled and made contact, and then run for a couple of minutes until the wire cooled, and then not run for the rest of the trip, lol.

My voltage in the cluster is kinda spastic, it reads high and drops a lot when any accessory energizes. I have control module voltage in my scanner channels, but it is in lightly colored letters instead of black, and it doesn't record when I scan. I guess I will have to delete and reinstall that channel.

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