No power when warm/bucking/surging.

[BBeach]

A little O/T but is that a scangauge II you have in the pic? How do you like it? Anyways, maybe you could use it to see if timing or map is out of whack. Is it an auto or manual? Could it possibly be something to do with the torque converter or NSS sending whacked signals.

 

[MisterFubar]

A little O/T but is that a scangauge II you have in the pic? How do you like it? Anyways, maybe you could use it to see if timing or map is out of whack. Is it an auto or manual? Could it possibly be something to do with the torque converter or NSS sending whacked signals.

Yeah it is a Scangauge II in the picture. I love it, I mostly use it as a trip computer.

I have been using it to monitor and troubleshoot and nothing it reads is out of whack while it's happening. MAP, TPS, Fuel Flow, Timing, and IAT all seem to be normal while it's "bucking"

 

[MisterFubar]

Had the problem again and this time I pulled over left it running and disconnected the IAC. The problem went away, but it was idling at about 900 rpm(motor stayed in whatever position it was in when I disconnected it)

Picked up a replacement IAC and she's been running like a top.

I think I'm going to go ahead and replace the entire exhaust and throw some new 02 sensors in, but my bucking/surging problem is now cured.

 

[jsorrels]

Cleaned throttle body IAC
Cleaned all sensor connections, checked/cleaned all grounds and even installed a few new grounds.

Good suggestions but I've done it all but check fuel pressure(I can't find my gauge). It's still only doing it when fully warmed up after about 15-20 minutes of driving. Here is a Video of what it's doing. I was giving it about 1/2 throttle.
http://www.youtube.com/watch?v=sGhvnhAAxLQ

This test was not done on a closed circuit with a professional driver. :looney:

My '95 does the same thing at 3K RPMs as well, I would be most interested on anything you find out.

[email protected]

 

[Fourxfour79]

Well, do the easiest and cheapest things first.

-clean your throttle body/lube the IAC
-clean your battery cable connections and ground connections
-check all the sensor connections while you are at it
-check your fuel pressure while driving (I actually rigged up a flashlight to shine upon the gauge under my hood and camera to record the gauge.)

Hey all, I know just enough about these things called xj's to be dangerous so I'm still learning (and learning and learning). There is a term in here that I'm not familiar with but probably will kick myself and go "Oh Yeah!" when I hear it...what is the IAC?

 

[CaptTrev]

IAC = Idle Air Control

 

[jsorrels]

My '95 is still doing it. It has no cat, I replaced the injector o-rings and the oxegen sensor. I'll try the CPS next.