surveyor75

I purchased a 94 JGC 5.2L recently.

It's been in the shop for 2 weeks now because of a rough idle.
Nothing more than glorified part changers
they have changed everything but the computer.

Last week they told me they were tearing back into the timing chain, as they thought it may have "skipped" ??? They put it on... they have looked for vacuum leaks and none found, all plugs, wires, rotor and cap replaced.
they have now pulled the distributor and said it looks fine.

I like the forum here and hope some help can be given...

ETA: throttle body was cleaned all sensors have been changed also.

ETA2: Just returned from the shop they have it running a 1200 to 1500 RPM's and can not get it to idle down. it just bounces between 1200 and 1500?? any help would be great...

Bustedback

Could be the Plenum gasket on the bottom of the intake manifold. That can cause a rough idle and oil consumption at the same time. Did the shop do a smoke check with a smoke machine to look for vacuum leaks? If they pump smoke into the intake they will see it come out of the oil fill cap if the gasket is bad. You could also have a bad EGR valve too if it has one.

surveyor75

Yeah I thought that too and had them replace it also and they swear they have looked for a vacuum leak.
I don't know if it has an EGR Valve I will find out this morning. At this point it seems like it would have been faster to just put a new motor in it and go from there.

surveyor75

Well just came back from the shop again...
they tell me that some seal for the brakes may be causing the issue and that there was a Service Bulletin about pinching the vacuum line for the brakes, and yet still can't tell me when it will be ready. Or what is truly causing the problem...

They made the offer of taking my Jeep elsewhere and would not charge me for any of the work done to date, but asked if they could finish it out and that they would make it right... I'm just at a loss...

Back to a rough idle and then dies (Note it didn't do that when I brought it to them it just ran rough) the only thing not changed so far...

Fuel Pump
Computer
Distributer
Fuel Injectors
Coil