1995 GMC PU engine miss

[T. Graham]

I have a 1995 GMS PU with 208,000 miles. Does not burn oil, new plugs; replaced plug wires, dist. shaft, rebuilt throttle body, O2 sensor, EGR valve all replaed and the truck continues to have a miss while idling. Any ideas????

[DaddyCool]

You did not say if the miss goes away above idle. If it does, I'd look for a vacuum leak. Be sure to check the power brake booster too.

Good luck,

Dave

[vett599]

Do a compression test of the cylinders.You might have a bad valve.

[jmedved]

Check for an intake manifold gasket leak. That could cause a miss at idle, that "seems" to go away when you get the engine speed up even a little bit. I don't recommend anything but using some WD40 or Carb cleaner while the engine is idling, squirt it around the intake manifold/head mating surfaces... if the engine reacts to it, you probably have found a leak. GOOD LUCK.

[vetteonr]

That's a good tip jmedved. I wondered before how to really tell if you had a manifold leak. Thanks!

[danny]

did your rebuilt throttle body come with a new idle air control(iac) solenoid?