Last post on Oct 29, 2013 at 2:17 PM
You are in the Jeep Cherokee and Jeep Grand Cherokee
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Jeep Cherokee, Transmission, SUV
#51 of 276 1997 Jeep Country Cherokee
Nov 25, 2007 (1:34 pm)
I have a 1997 Jeep Cherokee, with 120000 miles on it, that's experiencing some weird problems. Ocassionally the Jeep will lose acceleration and at the same time, the turn signals will stop working. The engine totally died on one occasion and had to have it towed. Took it to a Firestone Automotive shop and replaced the idle air control, fuel system tune-up and a new battery installation. Jeep worked fine for about two weeks until it experienced the same problems. The Jeep again lost acceleration and the emergency and turn signals did not work. The Jeep did restart again. Engine diagnostic analysis again could not find any problems. Does it sound like an electrical problem such as BCM?
#52 of 276 lrichter
Nov 25, 2007 (2:14 pm)
Crankshaft Position Sensor is always a suspect when things like this happen so next time it stalls / won't start try the unplug trick. Ya just unplug & reconnect the CPS connector and sometimes that will clear enough oxidation from the connector pins to let a bit of extra voltage signal reach the computer. This is not something ya want to swap out beside the road at 5AM so test the CPS following the general procedure at the bottom of this page and if it's bad - replace it. Easiest to replace if ya drop the transmission cross-member w/ a floor jack about 2".
(This is the one I suspect in your case.) Check the ground straps especially from the driver side of the head to the driver side of the firewall.
This page is for an earlier model XJ but AFAIK all the grounds are still run the same in later models. Jeep Cherokee Ground Straps These things cause all kinds of wierdness when they start oxidizing and/or get damaged / disconnected.
Check the electrical ignition switch - lower half, on top side of steering column. There is a downloadable "how to replace" zip file on my site if that's the problem.
Does it do this under any repeatable circumstances? (ie - always same distance from home, left turns, etc.... or just random?)
#53 of 276 Re: lrichter [lunghd] 1997 Jeep Cherokee
Nov 25, 2007 (3:41 pm)
Thanks for the awesome info. I forgot to add that another problem that happens with the jeep, alongside the reduced acceleration and non working turn signal, is that the jeep shakes before it konks out. Would a CPS problem cause major electrical problems, ie turn signal or dashboard problems? I'm probably going to take it to a Jeep dealer to have it looked at, but I sure would like to know what the problem is beforehand. By the way, the problem usually happens when the car is on the freeway, travelling a higher speeds.
#54 of 276 Re: 1997 Jeep Country Cherokee [lrichter]
Nov 25, 2007 (4:52 pm)
I had similar problems with my 99 Jeep. After I replaced the Idle Air Control, I had to get a new battery and then I had to replace the ECU Computer. After the computer was replaced, the keys would not work so I had to get a new key, a Crank Position Sensor and something else called the R&R ECU. I just got it back from the shop today. After $1500, it runs great now except now my oil pressure is dropping when I stop and the check gauges light is coming on. Any help with this one? I don't want to take it back to the shop and put more money into it. I think this will be the last Jeep I ever buy, but if it can last me a few more years I will take it.
#56 of 276 1990 jeep cherokee starting problem
Nov 25, 2007 (5:18 pm)
I have a 1990 cherokee that will start, but as soon as you let off of the key it will die. There is a new fuel pump and filter on. Put a new ignition switch in today and it still has the same problem. If I bump the start as it dies, sometimes it will stay running. Any help would be greatly appreaciated
#57 of 276 cold start wont idle
Nov 26, 2007 (12:09 am)
just wondering if any one can help me out. 4L straight 6. car wont idle when cold, once hot no problem. help me
Nov 26, 2007 (4:21 am)
#1 suspect w/ just that info: Idle Control Valve / IAS / idle stepper motor. (different names for the same thing).
Located in throttle body, easily removed and cleaned w/ carb cleaner.
#59 of 276 Hard to crank; TPS?
Dec 08, 2007 (11:33 pm)
'00 XJ L6 4.0 auto tranny
This Jeep has been giving me difficulty cranking for quite a while, however it got worse and worse every day this week. This last time, it took at least 15 minutes to get it to fire up, whereas it would normally crank after a minute of trying.
The trouble occurs only the first time the Jeep is driven for the day. Once it cranks, it's good to go for the rest of the day, and will fire right up if I just drive it a mile and park it for 30 minutes.
When I turn the key, the engine will try to crank, but just won't fire up. Usually after several attempts and turning the key off and on, it will finally crank. Sometimes a cloud of gray smoke will blow out the exhaust when the engine finally cranks.
Often, the engine will start to crank but die and blow off a vacuum hose. Lately, when the engine cranks, it won't stay on unless I press the gas pedal to keep it idling. If I let off the gas within a minute or so, the engine will die. After a minute of manual idling, it's good for the rest of the day with no problems.
After reading all the previous posts, it sounds like the Throttle Position Sensor could be the culprit. Another factor that could point to the TPS is that the transmission will sometimes come out of overdrive. Would the TPS cause cranking trouble or just idling trouble? I guess I could go ahead and pay $50 for a new sensor to see if there is a difference, and return it if not.
#60 of 276 timmer23
Dec 09, 2007 (1:39 am)
If the TPS thinks your engine is already running it will feed the ECU/PCM the incorrect information. You can check it's function with a $5.00 digital volt meter.