MeanYellowZ

Alright, engine is 305 MAP TPI, all new, less than 400 miles. I ran into some problems getting it running initially, but it more or less runs now. My problem, is a idle that still kind of searches, an SES light, and whats I feel is a not right feel at higher RPM.

First off, I have a code 43 all the time, EST, I have replaced the distributor w/ module, I have a MSD coil, cap, rotor, and wires, and all new plugs. Still have a reappearing code. Here is the otehr odd part, the car had a SERIOUS bad idle to it before, as in up down, stall, up down stall, all over the place. That is how it runs with the timing at 6 degrees BTDC, at that setting the car drives bad, pinging and all around sounding like too much timing (slow cranking etc.) Anyway, I retarded the timing down to the point where it runs pretty good all around, this is about an inch below the timing pointer. I dont know if the balancer may have slipped or what. I do know that I looked at it first and checked and the tine for timing and the keyway are almost lined up, which is usually how you tell a later balancer that uses the center pointer from one that uses a side pointer. I dunno what the issue is there, but i am sure that the car wont run with it at 6, so something somewhere is off.

Okay, now onto the rest. the idle seems to go in and out and the engine seems to do it all all RPM ranges....not in and out bad, but just noticeable, but Im picky. I installed an Air/fuel guage and it goes from the stoich range to lean and back and forth, almost rythmic, even when youa re just at cruising highway speeds, is this normal?? It goes right off the guage to the lean side for the most part. Back and forth and back and forth, however it does go into the rich side and stay there solid at WOT which leads me to believe that the O2 sensor and the guage are working, or it would still go back and forth then.

What could this be?

here is some more info:
fresh .030 305 MAP
replaced ALL ignition
All new coolant sensors
had all injectors cleaned and flow tested individually
new fuel filter
good fuel pressure
new o2


????

rezinn

Sounds like you have a loose connection at the ignition coil or the distributor itself, have you checked to make sure everything is making good contact?

MeanYellowZ

anyone else?

KNTA4DNU

Are you sure the distributor is in correctly? One tooth off could put your timing mark on the balancer way out of wack, but the engine will still run. Also, unplug advance wire when setting timing.
When I put my heads back on, we had the rockers a little too tight. It surged a little at idle, like the computer was searching, and it lacked power and stumbled under acceleration. I adjusted them with the engine running (1/4 turn past the quiet point) and it made a world of difference.