What are the symptoms of a manifold gasket leak other than rough idle/miss?

 

the fuel trim would be lean at idle but normal at 2500 rpm. if you have a 99 to 06 5.3L, its common.

 

Any chance I would be getting an intermittent coolant leak as well?

thanks,
Tim

 

yep. it should be easy to see the wet trail left behind. and the model year is?

 

Anything from 95 to 05 is common. Rough idle (vacuum leak), coolant in oil, coolant leak, could all be from this.

 

Hi Tech2

The Tahoe is a 2007 5.3. I have looked for a coolant trail and I can't find it.

It seems to be more prevalent after driving on the highway at 65-70 mph for awhile. Then park it in the garage and there will be a spot or two a quarter to half dollar in size. I'll wipe it up and then it won't leak for awhile.

I have pressure checked the cooling system and it doesn't lose pressure?

Thanks,
Tim

 

Water pump seal?