I just bought a 92 Formula 350 with 69,000 miles about a couple of weeks ago. The car was parked and driven only 600 miles between early 1998, and now. Its in really nice shape. It seemed to be in need of a tune up, and I did all the normal stuff, plugs, cap and rotor, etc. (It came with Accel 8.8s) It just doesn't run nice and smooth like my IROC did; rather, it chugs (rapidly at idle) as if it had some kind of wierd cam, and hesitates. Power seems to be lacking as well. Coming to a stop with your foot on the brake, it jerks real bad. It doesn't really sound like a TPI car either; more like a friends beat up 72 Mopar with a worn out 318. I set the timing with the ECM wire disconnected, and today I was driving it and got the SES light. Codes 32 and 42. Disconnected battery, replaced ignition module, drove car again. No SES light or codes, but still runs bad. Ever rare once in a while, it seems to run real good for a bit, and sounds awesome too. But that doesn't last long at all, maybe for about 5 minutes tops. I don't want to have to sell it already, help!

 

The code 32 is talking about your EGR valve. You may want to get that checked out or replace it. How does the car run ice cold? The injectors may be in need of a cleanout also. You may want to get a vac guage to it and see how much vac your getting. It low vacume a leak somewhere may prove to be the culprit. Also change the fuel filter. It could have sucked up alot of stuff while sitting there for a while and plugged it up.

 

Well, I tried a couple more things. I reached under the plenum to manipulate the EGR valve, and it seems to be okay. If I push up on it, the car idles real bad. If I release it, it goes back to close, but that annoying chug is still there. I swapped coils with the one in my Chevy truck; same thing. It shakes the whole car side to side at idle, and is especially bad at about 1700 RPM. Still no more codes though. Theres an aftermarket thermostat housing installed, and the temp gauge only goes to about 185 or so. Perhaps an aftermarket chip of some sort??? I'll check. Anymore ideas?

 

Check your timing again after you drive the car, but don't shut it off. Leave it running and see if the timing goes back to 6 or whatever you set it at. You may have the same problem I do, timing is locking at 35 or so at idle. Also check the fuel pressure and filter. Let us know what you find.

 

Did you double check that you got all the spark plug wires on the right cylinders, it is easy to switch a couple around. It is always worth checking again. nick

 

Uh, that's exactly what it runs like, wires being crossed. I thought for a minute that a couple were crossed up, and switched them. It ran just like it did before, so I switched them back and got the book out to check them all. I then tried the test where you pull each wire off, and look for an RPM drop. All wires caused a drop when removed except: #7. I thought I had found the problem, but I guess not. I tried swapping good wires in for #7, and still no change. The #7 injector is clicking just like all the others, but the car doesn't seem to care if I hook up #7 plug wire or not. Yes, good spark shoots from the pole on the distributer. I give up. Score: Car=5, Me= 0.

 

Run a compression, or leakdown test on the number 7 cylinder. (yeah, I know, it' a real b1tch.......) See what kind of results you get.

 

Hey, have you tried pullilng that #7 plug to see if its fouled? I had a plug not firing for a while making it run like crap. I did all sorts of troubleshooting but didnt pull the plug because it was a pain to get to. When I did finally pull it out, it was all fouled up. I replaced all of the spark plugs at that point and it ran fine afterwards. Hopefully your problem is something that simple. Good luck

 

Well, after shocking myself pulling off plug wires for the last hour, I just started checking all the electrical connections. At last, I found the connector for the #7 injector wasn't plugged in all the way! Plugged it in, and now it runs great! Thanks for all the advice. One thing still baffles me though- how come it didn't set off the SES light for that being disconnected? Has anyone else had an injector connector just pop off? That seems unusual....

 

I'm glad you got your chugging motor running right.

I have never had an injector connector come off. They are usually a pain in the butt to remove since you have to push the "locking ring" in to remove them.

Chuck
'85 IROC

 

the ECM doesnt "monitor" the fuel injectors. it only sends current to them one direction. no diagnostics on them so it sets no SES