OK, I discovered that everything under the hood of my coupe that is rubber or plastic has about the same brittleness of bones lying in the desert for 145,000 years....especially the vacuum lines...which probably has quite a bit to do with my wandering idle...I completely removed the fuel injection system down to the manifold...I got copper tubing to replace the plastic lines and when I'm done porting and polishing the plenum and runners, it's all ready to go back together...

However, upon looking into the manifold runners, it looks as though there has been cigarette smoke blown into them for about 20+ years...I'm talking a 3 pack a day habit...it's brownish(maybe the light) but it is almost tar-ish in composition. It is translucent but gooey/sticky...I am wondering how this can be considering that there is only air that passes through here...

Is there anything that is safe to spray into the manifold runners without removing the manifold that will get rid of this...I don't want to take it off the car for 2 reasons:

1). the car basically runs well except for the idle and if I take the manifold off I won't stop until I get to the camshaft because I'd like it to go a whole lot faster and I need to wait until I can afford to do an LSx swap...I don't want to spend the cash to upgrade this L98 because I don't have it which means the car would have to sit until next year and I so want to drive it this year...but I get a little crazy when the engine starts coming apart...









2). What the first one wasn't reason enough?

Thanks



Moderator....please move this to the C4 tech forum....I didn't realize I was in the C5 section....Very sorry...

 

My first thought is that its oil blow-by coming in there via the PCV valve. A decent catch-can will help limit how much oil contamination gets through.

 

Well if you're not going to remove it until later, Sea Foam has been used successfully by a lot of CF members....With that much yuck, probably several applications are in order....then I would change the oil, just because....