1988 GMC k1500 5.7 tbi 5 speed runs fine when cold but misses when warm any suggestions?I

Tiny
D61562
  • 1988 GMC TRUCK
  • 18,000 MILES

I've changed fuel filter, egr valve, dist. Cap and rotot button, and pickup in dist.

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Saturday, December 10th, 2011 AT 4:42 PM

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Tiny
JDL
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  • 16,281 POSTS

You might do a cylinder balance test, when the problem is ongoing. You usually kill the cylinders one at a time, quickly, by killing spark, Pay attention to the rpms, if you kill a cylinder that has no effect on the rpms, that cylinder is either dead or very weak, then you check fuel--spark and compression on that cylinder.

Any applicable trouble codes? You can check mil codes, yourself. Use a gage and check fuel pressure, when problem is ongoing. You could have a vacuum leak that only shows up after it is warm.

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Saturday, December 10th, 2011 AT 5:55 PM

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