Edmunds.com | Inside Line | Auto Observer Your Account | Help | Directory
You are here:
![[F]](http://a332.g.akamai.net/f/332/936/12h/www.edmunds.com/media/townhall/webxicons/site.gif){kind=small}
Forums
SUVs Jeep Cherokee and Jeep Grand Cherokee Jeep Cherokee Grand Cherokee Engine and Performance Problems
566 messages, Last post on Nov 16, 2009 at 9:41 PM
You are in the Jeep Cherokee and Jeep Grand Cherokee Forum. Your Hosts are steve_ & tidester
|
My truck has been out of commission for a while now. I'm thinking that its my fuel injectors after inspecting several sensors. Here is what my JGC does when i try to turn it on: 1). As I try to turn it on it makes a clicking noise 2). when it does turn on the motor accelerates as if i was stepping on the gas and the RPM shoots up. 3). After a few seconds of (step 2) the RPM drops down as the acceleration decreases dramatically to a point were it wants to turn off. It continues to dance on the RPM scale from 1k RPM to 500 4). When i would step on the gas pedal it wouldn't respond only if i were to press it down several times. but it would come in delay periods in between after i press the pedal. 5).Finally it turns off on its own or when i try to shift it to reverse or drive. It be the obvious thing to take it to the mechanic but money is a lil tight right now so I'm open to any suggestions from anyone out there.  
|
|
|
Replying to: jeep323 (Oct 28, 2009 2:11 pm)
|
|
|
Replying to: tuggajb (Oct 29, 2009 1:52 pm)
|
|
|
Replying to: jeep323 (Oct 29, 2009 6:25 pm) |
|
|
This is a 1989 4wd 2.5l 4-cyl auto 2-door Cherokee. Granted that by design it's not very powerful... But in addition it has a really annoying quirk. When under hard throttle acceleration (what other kind is there with a 2.5l four?), motor doesn't seem to be pulling at full power. But when the throttle is backed off halfway or more, the motor actually "surges" and runs stronger at part-throttle than it does at full throttle. Also occurs in normal driving, just not as obvious. Not a misfire, just weak... For various reasons, over a couple of years, have ended up replacing EGR valve, dist. cap & rotor, wires, plugs, fuel filter, tried swapping fuel pumps, swapped to a different throttle body (& checked correct fuel pressure), replaced O2 sensor, catalyst (loose pieces were rattling around inside), replaced water temp and inlet air sensors, swapped ignition module and MAP sensor at one point or another, bought a new (high-altitude) CPS, etc. Last update was to add a "torquer cam" (great results from that). But still it surges. Took it in to Jeep dealer for analysis -- they "tweaked" the TPS setting, then told me their best guess is that this is caused by "a slow computer" (a $500 replacement based on a guess?). I've been in electronics many yrs; generally you either have a good computer or a dead computer -- a "slow" computer would have to violate numerous laws of physics... (the Renix CPU is like the Eagle; not much in the way of retained error codes or diagnostics to look at) Starts & runs (as well as can be expected), gets good mileage, but the non-linear throttle response is crazy. Any ideas, or anyone seen this on another Jeep? Maybe it's generic to the 4-cyl? |
|
|
Replying to: eric784254 (Jul 25, 2009 6:26 am)  aol.com
|
|
|
Replying to: bertt (Nov 13, 2009 9:19 pm) Let's keep the discussion here so everyone will benefit.  tidester, host SUVs and Smart Shopper |
|
|
Replying to: tidester (Nov 14, 2009 12:24 pm)
|
|
|
Replying to: bertt (Nov 15, 2009 8:11 am)
|
|
|
Replying to: steve_ (Nov 15, 2009 8:30 am) |
|
You are here:
Forums
SUVs Jeep Cherokee and Jeep Grand Cherokee Jeep Cherokee Grand Cherokee Engine and Performance Problems
New? Join Now!
Forum Tools
Search Forums
Browse by Vehicle
2011 Jeep Grand Cherokee
2001 Jeep Cherokee
Browse by Board
Browse by Topic
