Resolved : EGR vacuum leak

[3100 MPFI]

alright. I have been trying to work out all the small bugs on my 1995 Cutlass Supreme SL 3.4 DOHC, and this vacuum leak is starting to get to me.

First of all, I replaced the EGR to be sure that it is not the EGR itself, but it does the same thing. I got a new upper, and lower gasket, removed the old stuff, cleaned it up real good, none of the old gasket is left on the mating surfaces, and put it all back together.

It still does it.

When the car is running, my AC vents don't move off of defrost, but I think this is an unrelated problem. I had no idea the EGR was leaking, but I was spraying around the engine compartment with carb cleaner to check for a leak for the climate control, and when I hit the EGR with it, it stalled the car.

I have sprayed the hoses behind the EGR, and the vacuum lines near it. It only stutters when I spray the EGR itself in that area between the egr and the intake manifold.

Any idea what is causeing my leak?

[1988GTU]

Crack or sticking valve from an electrical issue.

[93Oldsdroptop]

Did you check your vacuum lines running to the ball under the left fender? The ones that go there under the battery are prone to cracking.

You could also take off your EGR valve and disassemble and clean it, that may help.

Plus did you run a small diameter brush thru the EGR line itself into the manifold? Sometimes they get very caked up with carbon and clog or otherwise severely restrict the flow.

[3100 MPFI]

the vacuum globe holds pressure. I pulled the line off at the check valve, and it vented.

I will try it with the connector unplugged first thing in the morning.

If it was the passage blocked up, then it would not be causeing a stalling problem when I sprayed it with carb cleaner.

[3100 MPFI]

i went ahead and ran out there and checked it. I unplugged the EGR electrical connector, started the car, and then started spraying carb cleaner. It still does it.

I have also replaced the EGR itself. Both the old one and new one does it, so it rules out a problem with the EGR itself.

I am starting to think it might be a problem with the EGR adapter.

Tomorrow I will take it apart YET AGAIN, and see if there is something I am overlooking. Either a problem with the adapter, or the intake manifold itself.

[3100 MPFI]

Okay. One problem fixed, and I caused another one.

The EGR ADAPTER was messed up. I replaced it with a different one, and that solved the vacuum leak problem.

HOWEVER, when I was trying to get the old one off, I guess I cracked the EGR tube, so now I have an EXHAUST leak.

SIGH

I have a spare one, but it is not in any better condition. I dont think it is cracked at least, but it is creased pretty bad. I guess as long as it does not leak, then it will be fine.

[pocket-rocket]

If you have the EGR shut off in the ECM, why not just plug the hole in the exhaust manifold? Or do you have emissions testing down there?

[3100 MPFI]

We have emissions testing down here. As for shutting off the EGR in the ECM, this is a 1995. OBD 1.5 CRAP.

I want it to work, but if it comes down too it, I will block it off until I can get a new tube. I need to be able to drive the car.

[3100 MPFI]

okay. It is FINALLY fixed.

Here is the original setup that was causing the VACUUM LEAK.

Notice that there is only HALF of a gasket in there.



After I fixed the vacuum leak, I then had an exhaust leak. Here is my EGR tube that I removed from my car.





Yup, it was in 2 pieces.

This is the new pipe that I put in.





It was a little creased at the end where the EGR adapter goes, but it does not leak, and that is the most important thing.

I also took some pics of the working conditions.

Here is the car as I worked on it.



big ass fan to keep me cool.



And the temp at like 6 PM.






I also fixed the vacuum leak that caused the interior vents to not work. I now have AC vents. Now I just need a can or 2 of R134a and I am good to go.

[Rhedalert]

nice!

[pocket-rocket]

big ass fan to keep me cool.

Literally since it was blowing on your back side :P

[3100 MPFI]

Why do you think I had it there, instead of on the side of the car where there is more room? I am told I have a hot ass, and I love my ass being.....

never mind.