good idle, will rev in park, misses under load
#1
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Year: 1989 Laredo
Model: Cherokee
Engine: 4.0 ltr
good idle, will rev in park, misses under load
so I hope ya'll can help a girl out. 89 4.0 bought stock with an oil leak...drove it for 4 months with zero problems..built it up with 3" lift bumper winch etc...went wheelin a couple of times, got stuck in a mud hole, got pulled out drove it dirty for a week and then drove through a car wash...neutral safety switch started acting up..when wheelin again did great, got muddy, washed it...now it's missing like my mom's middle tooth.. I have....changed the fuel filter, pulled all the plugs and cleaned them out, pulled all the injectors and cleaned them, seafoam in the intake, seafoam in the fuel, removed the exhaust including the cat (have a new one on the way..have not driven it other than testing) cat was plugged and melted, muffler was crushed. injector cleaner in the fuel. I have not dropped the tank, I do wonder if the fuel pump is getting stopped up. I also noticed tonight that the voltage gauge is reading zero. I also pulled the distributor cap and cleaned the contacts and cleaned the button. I am trying to eliminate before spending bucks...they told me at the parts store that the egr was stopped up $139.00...
Help me Please! I have spent all this money lifting and 31's winch etc...now it won't go.
basiclly it is missing under a load. Will rev in park and will idle fine.
thanks for your help!
Help me Please! I have spent all this money lifting and 31's winch etc...now it won't go.
basiclly it is missing under a load. Will rev in park and will idle fine.
thanks for your help!
#2
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Year: 1998
Model: Cherokee
Engine: 4.0
Sounds to me like more of an ignition problem then a fuel problem. Fuel problems usually seem to make it bog down where as an ignition problem usually causes a miss. My guess is something got wet. You can try to get some silicone spray or contact cleaner and start unplugging connection and spraying them down.
#4
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Year: 1994
Model: Cherokee
Engine: 4.0 High Output
I had the same problem with my 94. I replaced my ignition coil and my had my injectors cleaned. Now it runs like a champ so i think it is more of a ignition problem than a fuel problem. Could be wrong tho, keep us informed
#5
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Year: 1999
Model: Cherokee
Engine: 4.0
If any water got under the hood, there are 2 components that can create your symptoms.
1. The throttle position sensor
2. The distributor cap
I'd consider replacing both of them or at least removing and baking out (low temp) the distributor cap.
1. The throttle position sensor
2. The distributor cap
I'd consider replacing both of them or at least removing and baking out (low temp) the distributor cap.
#7
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Year: 1989 Laredo
Model: Cherokee
Engine: 4.0 ltr
distributor cap
pulled the distributor cap off yesterday and checked it..looks great I scraped the contacts a little and pulled the button and cleaned it off too. No help. It will run good at idle and in park and neutral will rev fine. Distributor had a little dried mud down in the bottom but nothing major, no mud spots on the cap at all. I am about to give in and send it to the mechanic...I hate to concede, for the simple fact that no one ever believes that I can do it but I am stumped...coil maybe?
I'll pull the plugs on some sensors tonight and get back with ya'll...thanks for the responses
I'll pull the plugs on some sensors tonight and get back with ya'll...thanks for the responses
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#8
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
Could be a bad fuel pump or a clogged filter, ignition coils do not go bad very often. Check the fuel pressure.
Last edited by Bustedback; 01-04-2011 at 10:03 PM.
#12
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Year: 1989 Laredo
Model: Cherokee
Engine: 4.0 ltr
had to go help my Dad put his flag pole back up last night. I didn't get a chance to work on it at all. I'll try and do some stuff to it today at lunch and tonight. With the time change I barely have 15 minutes before it get's dark and no garage AND I am a big sissy when it comes to getting cold...I vow tonight to pull the tps and check it out...is the test pretty easy for that?
#13
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Year: 1989 Laredo
Model: Cherokee
Engine: 4.0 ltr
So, last night I went out and...pulled the tps from the tb and cleaned it with pb..no help, I did not test it as I do not have a tester. I also unplugged connectors and sprayed them out. I also had the Husband Half get in and hold the brake in drive while I looked for any sparks under the hood and around the distributor, no sparks. I will read up on testing the tps and try that tonight if I can acquire a tester
#14
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Year: 1989 Laredo
Model: Cherokee
Engine: 4.0 ltr
finally
So I finally got the jeep back and because I hate reading a thread that doesn't have an ending here is the rundown.
Fuel pump went out...lost the sock and was sucking up some pretty nasty stuff. Injectors were cleaned and the TPS was adjusted..(I screwed it up). $300 cash.
Alternator went out 1 day later add another $120 $65 + tax and labor..(too cold for me to do it).
now the fuel gage does not work..got under it and checked and it does not look like a new fuel pump..looks old..gonna take it up with the guy today..gage shows empty with the light on, I wiggle the wire and it shows over-full...wtf??
Took it out yesterday for a test spin...and guess what tensioner pulley went out...the ONLY reason we made it home was the screw that holds the hose clamp on the hose on the thermostat housing kept the pulley in place (sounded like 10 cats in a blender) $17.50 at autozone...so my one pretty day 50* I had to spend it working on the jeep and not driving it...
sucks but those are the breaks I guess!
Fuel pump went out...lost the sock and was sucking up some pretty nasty stuff. Injectors were cleaned and the TPS was adjusted..(I screwed it up). $300 cash.
Alternator went out 1 day later add another $120 $65 + tax and labor..(too cold for me to do it).
now the fuel gage does not work..got under it and checked and it does not look like a new fuel pump..looks old..gonna take it up with the guy today..gage shows empty with the light on, I wiggle the wire and it shows over-full...wtf??
Took it out yesterday for a test spin...and guess what tensioner pulley went out...the ONLY reason we made it home was the screw that holds the hose clamp on the hose on the thermostat housing kept the pulley in place (sounded like 10 cats in a blender) $17.50 at autozone...so my one pretty day 50* I had to spend it working on the jeep and not driving it...
sucks but those are the breaks I guess!
#15
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Year: 1994
Model: Cherokee
Engine: 4.0
The miss sounds like bad wires even though you don't see sparks. If I'm not mistaken the fuel pump itself is in the tank. If the pump alone was changed and not the pump and float unit together you will not be able to see the new pump. Ask the mechanic. The gauge problem sounds like a bad connection or ground at the tank. If you ground the fuel gauge wire at the tank the gauge will ether read full or empty. Take the ground away and it will read the opposite. That will tell you the gauge is good>