N1ghtM0nkey

Alright so I've got some strange problems at idle.

The first strange problem is that it sounds like it's missing at idle, but it doesn't miss at any other RPMs. However the other day doing a 4th gear ripper on the highway it missed once, and that's all.

The second is running incredibly rich at idle, and possibly other RPMs as well, but it doesn't feel like it. At idle there is fuel coming out of my exhaust and it leaves a wet spot on my driveway if I let it sit there for a bit (side exit exhaust is angled down).

What I've replaced:
I just replaced the spark plugs today with NGK standard plugs gapped at .043". I haven't replaced the wires yet. I also replaced the vacuum lines from the MAP sensor to the throttle body, and the FPR to the intake manifold (or whatever that thing is). The distributor was changed last year since my last one bit the dust hard.

The MAP sensor says Denso on it, so I'm thinking perhaps it was changed at some point in time for whatever reason.

As far as other info about my car, it's a B16A (OBD-0) in a 91 HF chassis. I'm running a Zdyne swap ECU (perhaps that could explain it?) and my O2 sensors are wired up correctly. Could I possibly need to replace them? If so could somebody give me a part number for something I can find at Advance Auto or Autozone?

By the way, my idle does not bounce or flectuate at all. It idles perfectly other than these few issues. However at stop lights sometimes it'll act like it wants to die then all of the sudden it'll rev up to about 1k - 1.2k RPMs and then drop back down to 750 on the dot and stay there for awhile...then do it again.

I'm really confused, does anybody have any suggestions?

N1ghtM0nkey

Bump, I went out and bought two O2 sensors so I'm going to try installing those.

Only problem is that the O2 sensors on the B16 header are in a very tight spot...any tips or tricks to getting to them or getting the header off?

I've heard that you have to pull the engine to get the header out of the car...is this true?

N1ghtM0nkey

Bump again, replaced O2 sensors and it helped a little but it's still sputtering and running rich at idle. Still getting a misfire in the upper gears (3 and 4). Tach isn't jumping and the idle isn't jumping.

Any ideas?