Vac Leak? Crappy Idle Source?

[2dr_sedan]

RE: 87 SD GT

Well, I was listening to my engine run and noticed a couple of dry-rotted vacuum lines, and needed to be replaced. The one that goes to the MAP sensor to the backside under the intake was almost in half, so I decided to pull the upper intake off and see what others needed replacing... this is what I found when I pulled the upper:

I called the guy I got the car from he said the only time the upper was removed was 4yrs ago when he had the dealership install new valve cover gaskets... He said the car has never idled right, and even then, the dealer couldn't find out why.

Looks like whoever removed the upper, pinched the plastic wire loom while reinstalling... it's been that way for 4 YEARS!

I got it all back together (correctly), it runs perfectly smooth now... but I still wanna convert to mass-air.

Just thought I'd share this "experience" with yall...
Mike

 

[DMAN302]

Funny how finding a little item like that can have such an effect on how the car runs. I found a small plastic vac line broken just inside my passenger fenderwell..fixing it cured an idle problem I had been fighting for 2 yrs!!

 

[04sleeper]

Yeah. I would say that would cause a vacuum leak.

 

[HISSIN50]

Those old corrugated gaskets never did work too well.

nice work. be sure to check the vac hose on the front of the upper (goes to the charcoal cannister, IIRC) - it likes to rot from heat.

good luck.

 

[2dr_sedan]

After that incident, I decided to just replace all the vac lines...(one at a time) they are 18yrs old after all.

Mike

 

[super302]

i could see how that could can a vac. leak