Mechanics

3.4 ENGINE MISS WHEN WARM

Chevrolet Venture

1997 3.4 Chevy Venture, with 118,000 miles. Recently replaced head and intake gaskets, plugs and wires. Engine starts and runs fine when cold. As soon as the engine warms up, a severe hesitation/ miss develops. Engine doesn't throw a code. Should the coils be replaced when the plug and wires were replaced?
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Etz
October 19, 2007.




You need a break out box. Check the CPS and ICM before you get to the PCM. Inspect for damages/loose connectors.

Tiny
Rasmataz
Aug 3, 2007.
Found the CPS, reads 355 ohms. But cannot find any info on what it should read. Cannot find the ICM however, and hear that some of these had the ICM intergrated with the EEC.

Tiny
Co_ranger
Aug 5, 2007.
Try doing this: Here is a little trick that will literally show you if a DIS module and its crankshaft sensor circuit are working: connect a halogen headlamp to the spade terminals that mate the DIS module to the coils. A headlamp is recommended here because it puts more of a load on the module than a test lamp. If the headlamp flashes when the engine is cranked, the DIS module and crankshaft position sensor circuit are functioning. Therefore, the problem is in the coils.
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Tiny
Rasmataz
Aug 5, 2007.
Well, it ended up being none of that stuff. Corroded ground wire connection on the firewall. Thanks for your suggestions.

Tiny
Co_ranger
Aug 10, 2007.
Clean and inspect the MAF or MAP. Is engine running hot or normal?

Blackop555
Oct 19, 2007.

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