Update:
Changed the smog pump last night and have some improvement. Mechanic checked the O2 sensors and they appear to be ok, also the car is not throwing any codes or overheating. It still runs rough, like at a stop light, it's just shaking and not smooth like it was before the repair. It's running rich.
He's thinking the car needs to be driven to allow the computer to reset itself.

does that sound right and is there any other way to reset the computer sooner? It has power and gets up and goes, but it's just not smooth like it was before.

thoughts??

 

Bet coolant/water spilled on the opti when pulling the hoses and such to do the heads. Opti does not like water one bit. I'd double check the plugs/wires first. Also check the rockers and make sure none are too tight or too loose.

 

No every time you disconnect the battery the PCM (AKA computer) resets and that does not cause a rough idle. High idle, low idle maybe but not rough idle. Heck you can replace the PCM with a junk yard unit and it will not cause a rough idle.

 

yep check your rockers to make sure there not turned down to much. i would recomend 1/2 turn rather than the factory 350 recomended 1 turn. also would recomend setting them with engine running.

 

There is SOOO many things that could have gone wrong with this repair to cause a rough idle. The common ones that come to mind is bumping a plug and cracking it or having a intake gasket crack, either because of a defect or a mistake, a small stress on a 23 year old connector could be causing a bad connection. Also keep in mind it could have nothing to do repair and it is just a coincidence.

I remember one engine I rebuilt ran bad when I was done, I went over everything, The mechanic next me pointed out that sounded just like a bad ignition control module. That's what it was. On that engine the ICM is inside the distributer which I never even had apart.

 

The rockers were adjusted, backed them out a bit, and the car was still running a little off. Found a vacuum line that looks to be the problem. Unplugged it the line (drivers side) and the car is smooth. The mechanic will trace the vacuum line this weekend and see where it collapsed, until then I'll drive it with that line disconnected.
Thanks for all the input!!

 

very cool.

 

So this is getting a bit frustrating..the vacuum line was fixed and the car actually runs worse. I don't know how else to describe it except to say that it has moments of running rough and the longer I drive it the more I get the shaking. At night you can see the dash lights go dim and then bright again, just a bit, when the RPM's are jumping from about 500-800. It's not as bad as when I first got it back but worse now that the vacuum line was fixed. Mechanic is thinking it's another vacuum line. The car has a lot of power and when I step on it she goes and is smooth, but at a cruising speed you can feel periods of smooth and periods of rough. No warning lights, running at operating temp, and otherwise good. Any thoughts fellas?

 

You remember which vacuum line it was? Can you disconnect it and see if it gets better? It could be a clue.


Honestly these rough idle issues are one of the toughest drivability issues to track down. Even with a dealer grade computer diagnosis system and the best tech they can be a challenge. I doubt anyone on this form can help much other then to guess at stuff your mechanic probably already checked. Like I posted before there are just soooo many things it can be.

Don't worry about the dash lights it is normal in this situation. Once the alternator slows enough its out put drops off and you are running on battery voltage.