93 Chevy 5.7 tbi dies after being warmed up

[Sean714]

Ok, here's my problem. I have a 93 5.7 tbi engine in my 52' Chevy truck and have the problem of the engine dies after it gets warmed up. It seems to die while giving it gas down the road. I first had a problem of it not starting so I replaced the the control module that's under the distributor, and that fixed the problem. It drove fine for the next couple outings, then now it dies after getting warmed up. It will start after it does, but only when I turn the key all the way off then back to start mode. If I don't turn the key all the way to off position, it won't start. So whatever it is it has to get reset for it to start again, hope this makes sense. And advice or help would be great. It does have new cap, rotor, wires, plugs and like I said a new module in the distributor.

[ChevyTech]

My first guess would be the new distributor module is failing.

Did you put heat sink compound under the module when you installed it? Without it module failure is likely, very soon.

When the engine starts, the module is in the base timing mode, but as the engine starts the module switches to electronic spark timing. It may be your module is failing in the electronic spark timing mode and when you turn the key off it is switching back to the base timing mode.

Many auto parts stores in my area will test the distributor module for free if you bring it in.

Have you checked the ECM for trouble codes?

[Sean714]

Thanks for your response, I did put heat sink compound underneath the module. It is an aftermarket one from Napa. But I still have a feeling it's failing for some reason.so I ordered a ac delco one. I was kinda thinking it was the coolant temp sensor also , what you think?

[Sean714]

And I have checked exam yet, I don't have a obd1 scanner.

[Sean714]

I did also read somewhere online that a guy added a heat sink underneath the bottom of the distributor, which I thought was a great idea.

[ChevyTech]

Originally Posted by Sean714

And I have checked exam yet, I don't have a obd1 scanner.

You don't need a scan tool to get codes out on a 1993. All you need to do is to jump two terminals (A&B) of the ALDL.

Look at this link.
http://www.chevytalk.org/fusionbb/sh...php?tid/273660

[ChevyTech]

Originally Posted by Sean714

Thanks for your response, I did put heat sink compound underneath the module. It is an aftermarket one from Napa. But I still have a feeling it's failing for some reason.so I ordered a ac delco one. I was kinda thinking it was the coolant temp sensor also , what you think?

You're welcome!

You can test the coolant sensor.

There are specifications and instruction in these threads:
http://67-72chevytrucks.com/vboard/s...d.php?t=322811

http://67-72chevytrucks.com/vboard/s...d.php?t=379142

[ChevyTech]

Originally Posted by Sean714

I did also read somewhere online that a guy added a heat sink underneath the bottom of the distributor, which I thought was a great idea.

When you look at what they did to the later trucks it makes sense.

[jokerz71]

Originally Posted by Sean714

And I have checked exam yet, I don't have a obd1 scanner.

You don't have to have a scanner. Locate the diagnostic terminal.Use a jumper wire,or,even a paper clip between A & B terminals.Then turn the key to on.Don't start the vehicle.Watch the SES light.It will give a code 12.Your SES light will blink the code. 1 long flashfollowed by 2 short flashes = code 12.After code 12 flashes 3 times,the following codes will be any stored codes you have encountered since the battery was last disconnected,or,ecm was reset. For example 1 long flash,followed by 4 short flashes = code 14.
You can google the codes,or,look them up in a repair manual to find the most likely cause & fix.Each code will be repeated 3 times before going to the next code.

[Sean714]

The problem is when my grandfather put the engine and Ecm in, he didn't install the SES light, I do have the wiring diagram so I could tap that wire and a 12 volt bulb I believe. What's your guys take on doing that? And thank you. Dry much guys for this very usefull information, a huge help. As I've been scratching my head a lot lately, even sleepless nights.

[ChevyTech]

Wiring in a check engine light would be easy, and a good idea.

I have 1993 schematics.

I can double check the computer terminals to wire in the check engine light.

Are you using the 1993 computer?

Automatic transmission or manual? 1993 computer shifted 4L609E?

[Sean714]

Yea, 1993 computer with the 4L60. I believe it's the brown/white wire? That sound right to you?

[ChevyTech]

Yes,
Brown/White wire
Circuit 419
Small computer connector Terminal B9

Other side of the light is to power from the gauge fuse.

The computer grounds the wire to it, to make the light come on.

[Sean714]

Thank you very much Chevytech, that's a huge help for me. I'm gonna set the light up tonight and see if it has any codes it will spit out. I'll keep you guys updated on what happens. Thanks again for everyone's help.

[Sean714]

Well it ended up being a bad control module, the part that sits in the distributor. Thank you guys for your help, and a big thanks to Chevytech. My truck is up and running and I even took it to a local car show.

[ChevyTech]

You're welcome, and thank you for letting us know what the problem was.

Bad new parts right out of the box is getting to be way to common.

Electrical parts that fail very quickly is common place also.

I jokingly tell people it is because the kid making the part in China was distracted because he needed a restroom break and was not allowed to take one for another ½ hour.