You are here: Forums SUVs GMC Jimmy GMC Jimmy Misfiring, Backfiring, Spark Plugs

GMC Jimmy Misfiring, Backfiring, Spark Plugs

65 messages,  Last post on Feb 09, 2009 at 10:25 AM

You are in the GMC Jimmy Forum. Your Hosts are steve_ & tidester

What is this discussion about? GMC Jimmy, SUV

Messages Page 7 of 7 1 2 3 4 5 6 7 Prev Next Last

Go To Msg # Search This Discussion

#56 of 65 Re: Engine revving - sporatic [rickwb] by jlflemmons Aug 02, 2007 (6:02 am)
Replying to: rickwb (Aug 02, 2007 5:25 am) I have seen a similar symptom from a bad temp sensor. The sensor reads the engine as cold (even in the summer after running for a couple of hours) and richens the mixture, causing the idle to gain speed. Ended up having to use an ohm meter and compare the readings from the sensor to the temp and found it was off by 2X. Replies to this message: rickwb (Aug 03, 2007 5:59 am) rickwb (Aug 10, 2007 5:38 pm) tidester (Aug 10, 2007 9:13 pm)
#57 of 65 Re: Engine revving - sporatic [jlflemmons] by rickwb Aug 03, 2007 (5:59 am)
Replying to: jlflemmons (Aug 02, 2007 6:02 am) Thanks. I did get lucky enough to catch this thing in the act yestewrday and got it attached to some diagnostic equipment. Engine temp sensor seems to be reading and registering the correct engine temp. The Idle Air Controller does however seem to be malfunctioning. We'll see what shakes out.
#58 of 65 Re: Engine revving - sporatic [jlflemmons] by rickwb Aug 10, 2007 (5:38 pm)
Replying to: jlflemmons (Aug 02, 2007 6:02 am) JUST AN UPDATE - Seems it was the Throttle Position Sensor that was the culprit. We determined the problem by observing that it acted differently when cold and after the engine heated up. When hot the sensor indicated a 4 or 5% throttle even when no throttle was applied.     Anyway the Jimmy runs great after replacing that sensor.  Thanks for the input. Replies to this message: tidester (Aug 10, 2007 9:13 pm)
#59 of 65 Re: Engine revving - sporatic [rickwb] by tidester HOST Aug 10, 2007 (9:13 pm)
Replying to: rickwb (Aug 10, 2007 5:38 pm) Thanks, Rick! That's good to know.   tidester, host SUVs and Smart Shopper
#61 of 65 97 jimmy v6 by hdguy72 Dec 08, 2007 (11:55 pm)
i have a 97 jimmy 4x4 auto it has had a problem since i got it in the warm wheather it starts fine. but when i drive it i have to go 1/8 th of a mile before it will run ok it spits and sputters then just clears up but i still cant floor it if i do it sounds like a popping sound comeing from the exaust and it does this every time i start the car even after a 20 mile drive. then in the cold wheather it is worse i had to drive 10miles before it cleared up yeaterday then on the way home it just out of no where lost power. here's the kicker if i turn the car off then back on and drive a little further it will clear up both in warm and cold wheather but in the cold it will do this constantly for about 10 miles. PLEASE SOME ONE HELP !!!!
#62 of 65 96 Jimmy backfiring and misfiring by rhickson Nov 09, 2008 (7:41 am)
I have a 96 jimmy (4.3) with a 2000 engine. My sensors were used on this engine. It has a problem with random misfire. I have changed two distributer caps as well as the plugs and wires. I also had the O2 sensor (upper passenger side) replaced. The misfire always returns and now it has started backfiring. Should I also change the O2 sensor before the Catylic converter as well or am I looking at something else?
#63 of 65 Re: tricky sparkplug change [quickfox] by nljewell Dec 04, 2008 (9:55 am)
Replying to: quickfox (Apr 08, 2007 5:21 pm) I have a 99 Jimmy and I was going to ask the same question. Thanks for the ideas.
#64 of 65 97 jimmy extreme misfire by Dkiser22 Feb 09, 2009 (7:05 am)
I've got a 97 gmc jimmy with the 4.3, the car starts and idles fine,but is extremely choppy from idle to mid throtle,and runs smooth when wide open. I have replaced the plugs wires, rotor, cap, the mass airflow sensor and the tps, any ideas??? Replies to this message: rhickson (Feb 09, 2009 10:25 am)
#65 of 65 Re: 97 jimmy extreme misfire [Dkiser22] by rhickson Feb 09, 2009 (10:25 am)
Replying to: Dkiser22 (Feb 09, 2009 7:05 am) I did all that with mine (three caps & rotors). I ended up having the intake manifold gasket replaced and the intakes cleaned. I also found out that I had a weak gaspump so I replaced that as well. It works pretty well now. The intake cleaning was under $60 and may be worth your while to check into it

Messages Page 7 of 7 1 2 3 4 5 6 7 Prev Next Last

Go To Msg # Search This Discussion

You are here: Forums SUVs GMC Jimmy GMC Jimmy Misfiring, Backfiring, Spark Plugs