jeepie
Well-known member
I have been having a problem with a slight miss at idle and a slight pinging under load for a while now. Neither is bad and the car runs well, but both of these things have been bothering me. Since it is winter here I would like to try to fix both. The car is a 91 auto with about 45K on it, I really don't use it much so the following things I have replaced over the last couple years are still like new. I changed the plugs, wires, cap, rotor, egr valve and solenoid, injectors, fuel filter, removed the two pre-cats and installed a new main cat, O2 sensor, and knock sensor. I had the chip reprogrammed to have the fans come on earlier and I believe the rest is stock. I noticed that when I set the timing (with the connector disconnected) that the timing stays right on the mark (6 deg), when I turn it off and plug the connector back in and check the timing it goes off the scale ( around 15 deg before) but it is not steady and jumps around 4 or 5 degs. Is this normal ? I also noticed when I unplug the connector the idle is not steady it goes higer and lower, but with the connector pluged in it is pretty steady, except for the slight miss, is this normal ? Can someone tell me why when the connector is plugged back in (computer takes over) the timing goes up that much ? It is the same idle condition, I would think the timing should be about the same, since the engine is just at idle. I also have cleaned the IAC and TB which did not help the miss at idle, anyone have any suggestions, the car has done both things since I got it, but like I said these are not bad, but bother me.
Thanks.
Thanks.