Cherokee running too lean

[EekGirl96]

Alrighty guys I have a riddle that needs to be solved. A month or so ago my Cherokee threw a code about the fuel being lean. I was wondering what wouldve caused my Cherokee to run "lean" and how can I prevent/stop this?


Another thing is that my Cherokee started acting weird yesterday morning. She started up yesterday and idled weird(lower than usual) but thought nothing of it, when I got out of my class and started her to go to work she started, chugged out then started running(really rough and at low idle) so i drove her home(she felt sluggish and didnt accelerate as fast as she usually does). When I got home I turned her off then waited and turned her on again but she wouldnt turn over, what could be causing this?

I replaced the fuel pump yesterday thinking that thats what the problem was but it wasnt. The fuel filter was just recently replaced as well as the spark plugs so thats not the problem. Ive had a couple people say that its the fuel pressure regulator but want some more input.

Any help is greatly appreciated.

[4.3LXJ]

Fuel pressure is a possibility. The only way to find out is to put a gauge on it. One other thing is the O2 sensor. How long since you changed it? I am thinking it might be bad and the second sensor is picking up too much O2 after the cat

[EekGirl96]

I changed the o2 sensor last march(last year). Yeah people are also saying that it could be the o2 sensor, which would be an easy cheap fix so im hoping that thats it....ugh

[4.3LXJ]

They do wear out. But it isn't common to go all at once. Might check your wiring down there.

[EekGirl96]

Ill check it. Ive had a couple people saying it could be a vaccuum leak, either way it just happened randomly since she was driving fine on Sunday

[xj4life2]

Check the line from the MAP sensor on the firewall to the port on the side of the throttle body, very common for this one to pop off. I agree sounds like a vac leak to me also

[EekGirl96]

Hm ok Ill check that too. Im guessing Tony said that it could be the TPS and to test that out.

...got a nice little list going on with things to check lol

[Mudderoy]

Hm ok Ill check that too. Im guessing Tony said that it could be the TPS and to test that out.

...got a nice little list going on with things to check lol

Well the problem I have is I only have experience with 97+. The 1999 wouldn't start. Later I found out that if I pushed the gas pedal down just a little it would start fine. If I took my foot off it would die. It was the TPS, but I wasn't getting any codes.

[EekGirl96]

Well the code was a month ago and hasnt come on again(probably over a month ago). She was running perfect until yesterday morning when she decided to start all this shit...ugh Cherokees

[EekGirl96]

Well the problem I have is I only have experience with 97+. The 1999 wouldn't start. Later I found out that if I pushed the gas pedal down just a little it would start fine. If I took my foot off it would die. It was the TPS, but I wasn't getting any codes.

Also, im pretty positive that if I pushed the gas pedal down when she was having a hard time starting she wouldve just died then and there, not sure since I didnt try it but the way she was acting thats what I was thinking

[OrangeXJ]

I'm thinking vac leak also

[prerunner1982]

My first thought before reading anyone else's responses was also the O2 sensor and/or the wiring for it.

As far as vacuum leak, my experience with them is it makes the idle high. However, I suppose this may depend on where the leak is?

You may also check the Idle Air Control Valve (IAC). This could cause the low/rough idle and perhaps the lean condition.

I don't know about the not starting part though. I would suggest checking the distributor. If the distributor is worn it could cause the problems you described. Not making a good enough contact would cause a weak spark and not all the fuel being burned (lean condition). Once it got worse it may not be making contact at all for one cylinder causing the low/rough idle. And now it has completely broken and won't start at all... heck of a theory I know, but just an idea.

[EekGirl96]

Hm doesnt hurt to check...see you know something ;)

[cantab27]

does it not start at all now ???

[4.3LXJ]

He is right. Vac leak usually makes a high idle from too much air and then the injectors take care of the mixture via the O2 sensor.

[LizardRunner]

ok, I was going to chime in but everything I can think of that could cause this condition has already been covered.

[prerunner1982]

does it not start at all now ???


When I got home I turned her off then waited and turned her on again but she wouldnt turn over, what could be causing this?

[prerunner1982]

Amber.. you say "wouldn't turn over". Do you mean it won't turn at all, or will crank but won't fire/start? If it won't turn at all, then there may be bigger issues.

[LizardRunner]

You might try this thread http://www.xjtalk.com/showthread.php?t=5907&highlight=won%27t+start

[EekGirl96]

Sorry, was going to clarify sooner but got busy. She'll turn over the second time but wont actually fire up like the first time

[prerunner1982]

Sorry, was going to clarify sooner but got busy. She'll turn over the second time but wont actually fire up like the first time

Sounds like whatever was causing the rough idle/lean issue broke. I will stick with my distributor theory. :D

[EekGirl96]

Lol well ill check that as well, hopefully one of the solutions will fix the problem

...hopefully

[4.3LXJ]

amber, does "she" have a name, or does "she" forever remain nameless?

[EekGirl96]

"she" would be my cherokee

[4.3LXJ]

"she" would be my cherokee

I know, but does the cherokee have a name, or just the anonymous pronoun she?

[EekGirl96]

pretty much "she" every once in awhile ill call my cherokee "cricket" but mostly its just "she"

[4.3LXJ]

OK, :D

[EekGirl96]

lol all my vehicles are girls...is that weird...

lol

[4.3LXJ]

lol all my vehicles are girls...is that weird...

lol

Better keep them away from the boy Cherokees, or you might have some new kid sized XJs running around :love0007:

[EekGirl96]

Better keep them away from the boy Cherokees, or you might have some new kid sized XJs running around :love0007:

Aw, i wouldnt mind having little baby cherokees running around lol

[4.3LXJ]

They might look like those pink Barbie Jeeps :noevil:

[EekGirl96]

yuck, no theyd be little mini hell raisers

[4.3LXJ]

Maybe black and red, with little horns?

[EekGirl96]

there ya go...little demons

[4.3LXJ]

Don't turn your back on em, might stab ya with their forks.

[EekGirl96]

instead of forks, theyll have a wicked little front stinger and roof rack...im already picturing it

[4.3LXJ]

They can harass the barbie jeeps

[cantab27]

baby cherokees look like this???????

http://i469.photobucket.com/albums/rr52/cantab27/untitled-4.jpg

[EekGirl96]

:sign0026:lol oh they will

...they will

[EekGirl96]

baby cherokees look like this???????

http://i469.photobucket.com/albums/rr52/cantab27/untitled-4.jpg

needs to be more square and boxy lol

[EekGirl96]

Soo, after work we cleaned the connectors that go to the sensors in and around the throttle body and now she runs perfect

...hopefully that was the problem and nothing new pops up