: intake leak at rear of manifold



H-Dmechanic
10-12-10, 09:32 AM
what is the little plug for at the back of the intake on my 96 deville. its screamin like a banshee when its runnin. i take a screwdriver and pusk on it and it goes away. how bad is it for a removal of the manifold and replace that plug?

Submariner409
10-12-10, 11:55 AM
what is the little plug for at the back of the intake on my 96 deville. its screamin like a banshee when its runnin. i take a screwdriver and pusk on it and it goes away. how bad is it for a removal of the manifold and replace that plug?

At the throttlebody end or the power steering pump end ?? Could be a vacuum fitting or blank plug. Depending on year, there are several plugs and nipples on these manifolds.

There's no coolant in these manifolds, so removal/install is the fuel rail/injectors and 10 bolts plus the throttlebody connector.

Take a look in the parts diagram blowup in www.gmpartsgiant.com

Any chance you're looking at the PCV pipe from the rear cam cover to the throttlebody ?

H-Dmechanic
10-12-10, 01:12 PM
it is not the throttle body end. the other end by the ps pump.its a lil black plug down inside the center of the rear of the manifold. not pcv pipe.

Submariner409
10-12-10, 05:06 PM
it is not the throttle body end. the other end by the ps pump.its a lil black plug down inside the center of the rear of the manifold. not pcv pipe.

Within the last 3 weeks there was a very similar thread concerning a vacuum leak - I forget if it was in Seville, Deville, or Northstar performance, but the year was close to yours and there was a ton of pictures. The leak turned out to be a cracked elbow in the center indent hole in the manifold - P/S pump end.

All these engines have several variations on PCV pipe routing and manifold plugs, so if there's a vacuum leak anywhere in that manifold it NEEDS to be fixed - correctly.

Ranger
10-15-10, 12:45 AM
I think what you are talking about is the over pressurization relief valve. It's in the tunnel behind the P/S pump. You'll have to remove the manifold, but it's not that bad of a job.