Jeep has a slight miss at idle... - Pirate4x4.Com : 4x4 and Off-Road Forum

Po' riggity · 10-23-2005, 10:40 PM

The jeep has a slight miss at idle, and won't pass smog due to the miss. Ive checked all the vacuum lines, and thats not the issue. Anyone know what it might be? Im about ready to give up and just give it to a smog shop to let them figure it out, but I don't want to spend the $$ right now, as I don't really have it. The problem is, my temp moving permit expires at the end of the month, so I need to move it to a smog shop SOON if I can't figure it out on my own. Any ideas will be appreciated.
Scott

conefoot · 10-24-2005, 12:27 AM

Replacing the Throttle Positioning Sensor fixed a miss at idle I had on a '94 ZJ.

Danzig13 · 10-24-2005, 10:38 AM

yeap the (TPS)throttle positioning sensor was wore out and my jeep had just a slite miss at idle....but when the TPS got more ware on it the transmission wouldnt shift at all...there are ways to test it with a volt meter (it may have a dead spot in the sensor)

TSM_88YJ · 10-24-2005, 12:13 PM

EGR valve? Mine was messed up and caused a sort of a rough idle, hard to explain, so I cut it off and welded that plate shut. problem solved. but I live in bfe NC so smog aint a problem.

jeep_collector · 11-02-2005, 09:56 AM

Your post just doesn't provide enough info to really help you. It could be several different things. I went through this on my 90 YJ.

I found this website to be helpful when trying to pass smog:

http://www.off-road.com/jeep/tech/258bbd/

What are your smog readings? They can help identify the problem. How does the Jeep run in general?

gripguru · 11-02-2005, 07:54 PM

Quote:

Originally Posted by Po' riggity

The jeep has a slight miss at idle, and won't pass smog due to the miss. Ive checked all the vacuum lines, and thats not the issue. Anyone know what it might be? Im about ready to give up and just give it to a smog shop to let them figure it out, but I don't want to spend the $$ right now, as I don't really have it. The problem is, my temp moving permit expires at the end of the month, so I need to move it to a smog shop SOON if I can't figure it out on my own. Any ideas will be appreciated.
Scott

so is it on your 89?
do you have the factory carter BBD? stepper motor? 75.9 miles of smog equipment?
I have lots of questions, and more than likely some more that you wont be able to answer if its an 89. SMOG ONLY right?
A fully functional carb and electronics are really hard to accomplish on that rig. I tried three times in my 90 in Sacramento county, one more strike and they were gonna take the rig. I went mopar fi in the end, but did alot of mods to try and pass smog. Let me know some more details and I will do what I can.

10-23-2005, 10:40 PM	#1 (permalink)
Po' riggity HeiserOilMotorsports Join Date: Aug 2000 Member # 1515 Location: Lake Arrowhead, Ca Posts: 7,984	Jeep has a slight miss at idle... The jeep has a slight miss at idle, and won't pass smog due to the miss. Ive checked all the vacuum lines, and thats not the issue. Anyone know what it might be? Im about ready to give up and just give it to a smog shop to let them figure it out, but I don't want to spend the $$ right now, as I don't really have it. The problem is, my temp moving permit expires at the end of the month, so I need to move it to a smog shop SOON if I can't figure it out on my own. Any ideas will be appreciated. Scott __________________ Black Star Status!

10-24-2005, 10:38 AM	#3 (permalink)
Danzig13 Registered User Join Date: Oct 2005 Member # 56112 Location: Warsaw,Va. Posts: 3	yeap the (TPS)throttle positioning sensor was wore out and my jeep had just a slite miss at idle....but when the TPS got more ware on it the transmission wouldnt shift at all...there are ways to test it with a volt meter (it may have a dead spot in the sensor) Last edited by Danzig13; 10-24-2005 at 10:40 AM.

10-24-2005, 12:13 PM	#4 (permalink)
TSM_88YJ Registered User Join Date: Jun 2004 Member # 32364 Location: NW NC Posts: 29	EGR valve? Mine was messed up and caused a sort of a rough idle, hard to explain, so I cut it off and welded that plate shut. problem solved. but I live in bfe NC so smog aint a problem. __________________ CENSORED SIG: To view press alt+f4

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

10-24-2005, 12:27 AM	#2 (permalink)
conefoot Banned Join Date: Oct 2004 Member # 36563 Location: Sak-n-ur-tomato Posts: 47	Replacing the Throttle Positioning Sensor fixed a miss at idle I had on a '94 ZJ.

11-02-2005, 09:56 AM	#5 (permalink)
jeep_collector Registered User Join Date: Feb 2005 Member # 42449 Location: Santa Clara, CA Posts: 9	Your post just doesn't provide enough info to really help you. It could be several different things. I went through this on my 90 YJ. I found this website to be helpful when trying to pass smog: http://www.off-road.com/jeep/tech/258bbd/ What are your smog readings? They can help identify the problem. How does the Jeep run in general?