Does anybody know why my jeep is stalling while I'm driving? I've kinda got it to where I can keep it from stalling but not everytime.

 

I've been told it could be the TpS or maps..is this true?

 

break out your multimeter!

http://www.lunghd.com/Tech_Articles/...iagnostics.htm

when i first bought my 90 it had a low idle and stalled now and then. i ended up cleaning out the throttle body and IAC, it helped but didn't cure. i ended up doing a quicky fix and adjusting the throttle stop screw a little to give it a higher idle. ran like that for 2 years no issues, then i replaced all my old vacuum lines with new and my idle shot up a good 400rpm........had to adjust the throttle stop screw back to the stock position.

 

First off, do you have a multimeter and can you use it?

Multiple things can be causing your symptoms, not just one. There is no "silver bullet cure". It's gonna be necessary for you to invest some time in this or pay somenone else to do it. Don't get stuck on "this worked for me" from a variety of well intentioned responders because what worked for them isn't always likely to work for you..

Personaly, I would start out with a good throttle body and IAC cleaning. Search for that one. I've not done a write-up on that.

If you're interested, I can provide some other write-ups for you to start out with that will insure avoiding future problems with your Renix Jeep.

 

Yeah that would be great! Thanks for the tips.

 

Let's start with these. There are some write-ups on the throttle body and IAC cleaning which I really advocate, but I haven't done one yet. Whatever you do, do the ground refreshing no matter what. Those crappy grounds caused us a ton of grief at the dealership when these rigs were new until a guy from JeepTech gave us the heads up on it. I don't think these ground connections have improved with age, do you?
Renix Ground Refreshing
The Renix era XJs and MJs were built with an under-engineered grounding system for the engine/transmission electronics. One problem in particular involves the multiple ground connection at the engine dipstick tube stud. A poor ground here can cause a multitude of driveabililty issues, wasted time, and wasted money replacing unnecessary components.
The components grounding at the dipstick tube stud are:
Distributor Sync Sensor, TCU main ground, TCU "Shift Point Logic", Ignition control Module, Injectors, ECU main ground which other engine sensors ground through, Oxygen sensor, Knock Sensor, Cruise Control, and Transmission Sync signal. All extremely important stuff.
The factory was aware of the issues with this ground point and addressed it by suggesting the following:
Remove the nut holding the wire terminals to the stud. Verify that the stud is indeed tightened securely into the block. Scrape any and all paint from the stud’s mounting surface where the wires will attach. Must be clean, shiny and free of any oil, grease, or paint.
Inspect the wire terminals. Check to see that none of the terminals are crimped over wire insulation instead of bare wire. Be sure the crimps are tight. It wouldn’t hurt to re-crimp them just as a matter of course. Sand and polish the wire terminals until clean and shiny on both sides. Reinstall all the wires to the stud and tighten the nut down securely.
While you’re in that general area, locate the battery negative cable which is fastened to the engine block just forward of the dipstick stud. Remove the bolt, scrape the block to bare metal, clean and polish the cable terminal, and reattach securely.
Another area where the grounding system on Renix era Jeeps was lacking is the engine to chassis ground. There is a braided cable from the back of the cylinder head that also attaches to the driver’s side of the firewall. This cable is undersized for it’s intended use and subject to corrosion and poor connections at each end.
First off, remove the cable end from the firewall using a 15mm wrench or socket. Scrape the paint off down to bare metal and clean the wire terminal. Reattach securely.
Remove the other end of the cable from the rear of the head using a 3’4" socket. Clean all the oil, paint and crud from the stud. Clean the wire terminal of the cable and reattach securely.
A suggestion regarding the braided cable:
I prefer to add a #4 Gauge cable from the firewall to a bolt on the rear of the intake manifold, either to a heat shield bolt or fuel rail bolt. A cable about 18" long with a 3/8" lug on each end works great and you can get one at any parts store already made up. Napa has them as part number 781116.
A further improvement to the grounding system can be made using a #4 cable, about 10" long with 3/8" terminals at each end. Attach one end of this cable to the negative battery bolt and the other end under the closest 10mm headed bolt on the radiator support just forward of the battery. Napa part number 781115.
　
　
If you want to upgrade your grounds and battery cables in general, contact Jon at www.kelleyswip.com. He makes an incredible cable upgrade for a very reasonable price.
　
Revised 11-28-2011