Renix running funny

I have an '89 Renix/AW4. It very radomly starts to surge at idle really bad, it will ALMOST stall if its in gear, but the second I take off its gone. However this morning it start up fine and got me down the street about 1 mile before it started to act up, but this time I could feel it surging under acceleration. I have also noticed it seems to be running really rich. Now I already replaced the TPS but continue to have the issue. I dont want to just be throwing parts at this thing, so what should be my next step? Idle sensor, O2 seansors....?

I just did a little more research on the TPS that I installed. I think I took my reading off the wrong plug when adjusting it. However all the write ups I have seen are only for AX-15 XJ's, I cant find any with an AW4. Can anybody post a link for how to adjust a TPS on with an AW4, lunghd was helpful but again only for a AX15

my '87 has been doing a bit of this and I failed a smog test recently as well. My last sensor to check is the O2 sensor. Otherwise I think it could be in the ignition but I am not sure exactly yet. my TPS is fine, MAP is fine, am replacing a bad EGR tonight, if that fixes anything I will post up.

I will be watching this post.

Dave.

Renegade XJ said:

I just did a little more research on the TPS that I installed. I think I took my reading off the wrong plug when adjusting it. However all the write ups I have seen are only for AX-15 XJ's, I cant find any with an AW4. Can anybody post a link for how to adjust a TPS on with an AW4, lunghd was helpful but again only for a AX15

Click to expand...

PM me and I will send you a simple set of instructions for testing and adjusting both types of TPS on the Renix Jeeps. There are some out there with bad info.

Ok just an update. I got the TPS adjusted correctly, but the problem persisted. Nexted I moved onto the EGR valve, tested it and all is well. Next up was the EGR balist resistor, I have been searching around and can't find anything about testing it, however the terminals had alot of gunk build up, so I took a wire brush and cleaned it all up to make a better connection. After doing this I was no longer able to replicate the problem, perhaps it fixed it burst this point my XJ was at running temp and it never seems to act up then. I'll keep you guys posted on what it does tomorrow morning.

Also I tested the MAP sensor with no issues found. The Coolant Temp. Sensor is reading slightly off and the Manifold Air Temp sensor is totally off but I'm not sure if I was testing that one right. Anybody know if either of those 2 sensor can cause issues like this?

Anyway if it's still acting up tomorrow I'm going to go out and buy a fuel pressure gauge to check that next.

Sorry ahead of time if there are any spelling mistakes, I'm on my iPhone and it's a bit of a pain to go back and check