[Colin C]

Hello to all I am a newbie who just acquired a 96 1500 with a 5.9 in it. The problem I am having is a powerful vacuum through the oil breather that connects to air filter. The truck idles way high 1900-2300 but when I pull breather hose off air filter and put my thumb over it the idles levels out at 750. With the breather covered the truck runs horrible after a litttle while. I have checked for vacuum leaks but only found a few small ones which I fixed. This has me perplexed so any info you have would be greatly appreciated.

Thank you,
Colin C.

 

[berner]

The problem is that the plate on the bottom of your intake manifold has a broken gasket, you must remove intake to replace gasket, common issue.