So recently my car has been sitting at about -14 to -15 vacuum at idle and runs really lean. Once my car warms up the vacuum pick up to about -19 to -20.

So from what i've heard low vacuum is somewhat normal on warmup but its a bit annoying since it just dumps out exhaust gasses.


And if i turn the heat or the Ac on the vacuum drop down to -14 if the engine is warm, and if its not warm while running it and i press the clutch in the car will stall the rpms drop so much from it.

Id like to hear some opinions on this.

 

Have you tried using a boost/vac leak tester? I'd give you mine but Jeff still has it.

 

Definitely do a boost leak test, especially if you think the car is running rich. I'm guessing you think its running rich since you said it's dumping out exhaust gases. A major boost leak will cause the car too have too much fuel for the amount of air going into the engine and can cause a low vacuum reading. Also the car should have a lower vacuum at cold idle since the rpms will be slightly higher until the engine warms up. Try cleaning the throttle body also.

 

Ok, i made my own boost leak tester and instantaneously found a pretty big leak where the welding was done on my front mount piping.
I'll have to go up and get it patched and then check for more after.

 

I'd say that's a good place to start. I know that my vac at idle does change when I mess with the heat/AC, but I assume that's because of the added load on the engine of the AC compressor

 

Nevermind, its just the coupler.

I'm gonna go upgrade them with maybe a silicone coupler and some t clamps.

 

After the fix's, the vacuum was at -19 at warm up.
And with the AC on it was about -16 which is still a bit low but not nearly as rough as before.

 

That's normal with more of a load on the alternator.

 

After the fix, the misfires went down.
But my knock is far worse after logging.
But, my intercooler piping was layered in oil...
Should i check the seals on my turbo?

 

not as much vacuum is completely normal with a big turbo. how much stuff did you delete off the intake pipe? the more vacuum lines you delete will reduce overall vacuum. with your setup, id say -19 - -16 would be ok, unless you have retained every vacuum line, which im guessing you didnt.
as for the oil in the intercooler, how do you have the crank case breather setup? is it routed back to the intake? if so this could be normal after a decent amount of mileage. if you dont have the crankcase breather routed back to the intake, the turbo seals would have to be bad as thats the only way oil can get into the intercooler.