95BlackTA

Ok I was talking to a kid at work who builds muscle cars with his dad. I told him all my problems I was having(Which is : Rough idle after car idles for a bit and warms up, loud screeching at idle, ticking from pass side, volts drop at idle, loss of high-RPM power, running rich and pouring out whitish grey smoke alot at idle)

Now I know my intake manifold is leaking..I see all the oil coming from the back of the engine. Now people said that would also cause the screeching noise(like a belt slipping, but i have a new one)..and the ticking noise. But the kid was saying that just because there was a vacuum leak in the intake man, that shouldnt affect performance, cause thats just crank pressure, and people run open crank pressure or something(like what my valve cover breather would be)
Makes sense I guess?

So does that mean the intake man is some of my problems, but isnt affecting performance? Or was he just wrong about the LT1?
He seems to know his stuff...

palehorse77

I have the oil leak as well as the eradic idle. The screaching noise has me at a loss though. I can't imagine how that leak would create a screach.

Just from what you described and the frequency of cars with these leaks that run just fine, I'd be surprised if the source of these problems is the leak. just my 2 cents.

97WS6SCharged

The loud screeching and voltage drop at idle may be a bad bearing in the alternator, although that noise would probably get more high pitched as the motor reved up. As far as the white smoke from the tail pipes, does it smell like coolant? If so, you might have a blown head gasket.

95BlackTA

Brand new 170 amp alternator, brand new battery, brand new belt. So thats not the problem. I heard the ticking and screeching is coming from intake manifold leak cause its not air tight, and is therefore ticking and making noise. Thats why I asked this, to get a lil more info on this...

shoebox

The LT1 uses a closed system for crankcase fumes and pressure. The leak can upset the balance of air the pcm thinks is present, because all air entering the engine is metered by the MAF (same thing happens if you put a breather on it). The leak can introduce air that the MAF does not know about. The pcm will adjust fuel based on O2 readings, but the balance that should be there with no leak is slightly upset. It also depends on how big the leak is. Maybe the screech is air going through the leaking area-I don't know.

My philosophy is to fix what you know is broken and go from there. You may have multiple problems, but you are not going to solve any of them by hypothesizing about what is causing what. Fix one thing and then go on to the next issue.

FacelessZ

Isn't the white smoke out the rear reminescent of a blown head gasket? That and 'milky' oil...

95BlackTA

Nice explanation, thanks for it. ANd yea, I will def be fixing it, but was just wondering about what this kid told me was true or not. Guess not.

And it really does look like I have white smoke, but it doesnt smell like coolant, nor do I have milky oil. So I dont konw, I guess its just gray and looks white to me. Ill figure it out after I do the intake I guess.