<DIV class=smallfont>1994 Rodeo with surging idle, tried everything </DIV>
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</NO></TD></TR></T></TABLE>I am nearly at my wits end with this thing! I am a former Chry/Dodg/Plym tech (changed careers), and an avid DIY'er when it comes to my vehicles.

I have a 1994 Rodeo 2wd, with 3.2L V6 w/ 5 speed. I bought it off my Dad nearly ten years ago, who bought it new, and it has served us well. Now that I want to get rid of it, it has played havoc on me (feeling betrayed maybe? lol).

It has in intermittent problem. Sometimes it revs up to 2000-2500 rpms and back down below idle, up and down, up and down. Sometimes its just a few times and returns to normal. Sometimes it continues regardless of how far you drive it. sometimes it revs up and just stays up there. Other times it runs perfect. I have searched many forums and boards looking for an answer. I have even tried some suggestions from them out of frustration. I had a paid access to TSB's for this vehicle, but can no longer find the discs for it, so I am out of luck on that. Any help would be appreciated.

The following things have been done, some were needed, some were shots in the dark and some were "just because I was in there".

Intake manifold gaskets
Throttle body removed and cleaned 3 times
IAC removed, cleaned as well as IAC port, more than once
EGR valve and tube removed and cleaned
all vacuum hoses replaced
Plugs and wires
swappped out Coil pack and ignition module with used one
swapped out IAC valve with used, (cause carb spray will mess one up! Trust me)
PCV valve, hose, and grommet replaced
CTS replaced (when IM was off and its a B*&amp;^h to get to)
all located grounds under hood were removed, cleaned, repaired etc.
tested crank sensor per Haynes Manual
Tested TPS per Haynes Manual
Tested Charging Sysytem per Haynes Manual
visual inspection of PCM connectors
tested Power steering pump switch per Haynes

And no trouble codes!

I am sure I am forgetting something that I have completed.

Any expertise would be greatly appreciated. What am I missing. Anyone with TSB's or manual pages they could send me? Any Isuzu/Honda Techs out there? Anyone have the same problem and actually narrow down what solved it? (or are we all just driving around bucking like we are going for the whole 8 seconds? )

I am nearly ready to try anything reasonable.</DIV>
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I had this same problem. Replaced TPS and it did not help. Turned out to be a bad connection on the fuel pump. Redid connection and all has been fine since. Idle went up and down stopped running just drove me crazy. Hope this helps...Ed

 

Replace ECT. Computer thinks engine is cold. It' a bear though. Have fun.

 

i remember idle problems mostly caused by loose connections by the power steering reservoir,those,black,blue an green connectors.the terminals would loose connection there do to the torque motion of the engine.at the dealer we just used to take loose those connectors an slightly twist the terminal then reconnect them.the pcm wiring to the iac motor passses through them ,mainly the blue an green ones.we had a tester that would monitor pcm iac control.all it was is a fancy test light.even somtimes we would find the wiring harness damaged which would make an intermitant open.to find this just grab the harness near those connector an move them around while the engine is running to try to duplicte the concern....this is an actual isuzu factory tech assistance check that the engineers would have us do.an isuzu newer vehicle have the same problem.the 2000 modles also.that same bend around the pwr steering reservoir harnesses were breaking.causing wired check engine light codes an idle concerns,an even with the throttle cableless design,the reduce pwr light would come on with no throttle respone.i have put many engine harness on or repaired loose splicesEdited by: ISUZUGURU