Crank But No Start, With Error Codes.

[Jeremy Gordy]

Okay so i have a 1989 GMC K1500 5.7 that i just rebuilt the engine three days ago.

So here is my problem, the truck was running fine and i put 175 Miles on it and everything was running fine. Today i went to leave and it wouldn’t start.
It acted like it wanted to start on first crank but after that it would just crank over and it smelt flooded. i took all the plugs out and all the plugs were coated in fuel so i pulled all the plugs to let it dry out. I checked spark and everything was fine, and I’m getting fuel.

now after letting it be for a while i got it to fire up and run, but it ran like crap and the check engine light was now on as soon as it started.

These are all the codes I’m getting

•Code: 12 – Diagnostic (i know but i thought i would still add it lol)

•Code: 15 – Coolant Sensor Circuit

•Code: 32 – Exhaust Gas Recirculation (EGR) Failure

•Code: 33 – Manifold Absolute Pressure (MAP) signal voltage low

•Code: 43 – Electronic Spark Control

All of my wires are hooked up, I’ve rechecked everything over like 10 times I’m just at a loss now because this all happened over night, after i parked it from driving.
Any help would be great

Thanks,
Jeremy G.

Topic

[college man]

Seems like a communication error. check all the connections
and fuses. Check the pcm is plugged in.

[Jeremy Gordy]

Thanks College Man, I’m going back out to start checking everything over again. being a 89 do you mean the ECM instead of PCM? also if all connections are fine what sensor would you recommend to start maybe replacing.

[Ingvar]

[quote=”KGJC616″ post=122906]Okay so i have a 1989 GMC K1500 5.7 that i just rebuilt the engine three days ago.

So here is my problem, the truck was running fine and i put 175 Miles on it and everything was running fine.
smelt flooded. i took all the plugs out and all the plugs were coated in fuel
now after letting it be for a while i got it to fire up and run, but it ran like crap and the check engine light was now on as soon as it started.
•Code: 15 – Coolant Sensor Circuit

•Code: 32 – Exhaust Gas Recirculation (EGR) Failure

•Code: 33 – Manifold Absolute Pressure (MAP) signal voltage low

•Code: 43 – Electronic Spark Control

[/quote]

Hi Jeremy

I high lighted main points for you.
General rule of thumb is – always go to the last repair.
When you rebuilt the engine, chances were high something was not connected back right.
For example – did you have injectors removed? If yes, did you REPLACE the O-rings with new ones? As those are basically single use rings, every time injector is out, you need to replace them with new one. And it has to be GM one, as sometimes they put strange shapes into them.
I’d safely guess your EGR code is due to exhaust blust from flooded engine. But it now needs to be taken apart and cleaned.
Btw, you do not clean flooded plugs by “letting them dry”. Does not work too good. Petrol has all kinds of additives and oils in it, and when you DRY it out, all that covers your plugs with sediment. Best is to take pliers to plugs, to hold them, and burn them white hot, the electrodes, to actually burn out ANY deposits.
But this does not change the point of leaking something relevant to petrol supply. Either the o-rings are not sealing, or injectors stay open, or got sticky.
You need to check you coolant sensor and clean your MAP sensor in air intake. Use ONLY dedicated cleaning spray, those are easy to damage.
I think, it mostly goes to fuel dumped into combustion chambers. So start with checking on your injectors/o-rings.
Tming may be off a bit too. That’s checked with strobe light.

[college man]

[quote=”KGJC616″ post=123000]Thanks College Man, I’m going back out to start checking everything over again. being a 89 do you mean the ECM instead of PCM? also if all connections are fine what sensor would you recommend to start maybe replacing.[/quote]

Chevy/GMC usually call the ECM a PCM which is the same thing.
sorry for the confusion.

[Lorrin Barth]

Sensors fail but they fail one at a time, not in bunches. Wiring.

[Jeremy Gordy]

Okay so I have been looking up different things and I’ve got an idea on why the “ESC code” is popping up. My thought is that computer is trying to advance timing more because it is quite a bit colder out now.

when I rebuilt the engine I put in a (Elgin Pro Stock E-923-P “Camshaft Specs“) camshaft, and the timing was set around 20+ Degrees Adv. when running and it ran fine, well when I got it started today the codes were still there and the engine was pinging.

I don’t have access to a degree wheel so i set timing chain dot to dot, during engine build. Any in-site on my current theory would be great. I’m also thinking this could be causing the MAP sensor problem as well because vacuum in the intake is incorrect from bad timing.

Sorry for the long post. I could be way off base here with my theory here I’ll be the first to admit I’m no professional Mechanic lol B)

oh I did go back through again and checked every connection and they are all good, even the ECM.

[Mike]

[quote=”barneyb” post=123020]Sensors fail but they fail one at a time, not in bunches. Wiring.[/quote]

This is quite probable. It’s really common to run a common power supply or common ground for a bunch of engine management sensors. Since everything was just apart, the likelihood of a ground terminal being loose or not attached is higher, as well as the possibility of having an old wire break when bending/folding wiring harnesses out of the way during the job (which could be power or ground).

[danny]

had one that done the same thing I changed the ignition control module fixed it
and my truck was firing before I changed it I was told to try it and had the spare parts
so I tried and it indeed did fix it so it can still fire and be a bad module I guess but its worth a try also I’ve been told a bad temp sensor would cause the problem I am no mechanic just offering suggestions lol

[Author]

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