89 cherokee running bad
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Joined: Aug 2011
Posts: 43,971
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From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Okay so..... I have changed every sensor, except knock sensor and EGR on manifold.... new ecu, Drained gas, New fuel pump, filter fuel rail ,fuel reg, all injectors, all vacum parts, distributor, rotor, plugs, wires, throttle body, compression check 135-145 all cylinders... still has a miss on accelleration???? I'm at a loss... Please help!
Also good fuel pressure 31 psi, I'm thinking maybe prev owner has timing chain off a gear ...?? idk...
Also good fuel pressure 31 psi, I'm thinking maybe prev owner has timing chain off a gear ...?? idk...
Thread Starter
Junior Member
Joined: Dec 2011
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Does a 89 jeep Cherokee have a device that holds the prime. While the jeep is turned off. Mine seems like it is losing the fuels prime if it sits for a while. If it sits overnight I have to pour a little gas straight into the motor just to crank it.
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Joined: Aug 2011
Posts: 43,971
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From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
The fuel pump primes when you first turn the key to the ON position.
You can have some leaky injectors letting the pressure off rather quickly.
Are they original?
You can have some leaky injectors letting the pressure off rather quickly.
Are they original?
Newbie
Joined: Dec 2011
Posts: 2
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From: P-Town
Year: 1989
Model: Cherokee
Engine: 4.0l
I'm having a similar problem with my 89 XJ. The injector on the #5 cylinder is stuck open, I have replaced the injector, cps, and checked the wires in the distributor. Could it be the computer not sending the signal to the injector to close?
Member
Joined: Sep 2011
Posts: 248
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From: Oklahoma
Year: 1994
Model: Cherokee
Engine: 4.0
Originally Posted by 89' XJ
I'm not sure if they are original or not. But I would say they were. How do you check to see if one might be leaking?
Member
Joined: Sep 2011
Posts: 248
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From: Oklahoma
Year: 1994
Model: Cherokee
Engine: 4.0
Originally Posted by jeepinitinfl
It is not really as miss... wrong wording . it just stumbles under load..
Member
Joined: Sep 2011
Posts: 248
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From: Oklahoma
Year: 1994
Model: Cherokee
Engine: 4.0
Originally Posted by cruiser54
Guys, you have to verify that your tune-up hardware is in good shape. It's hard to tell by looking at wires. The factory interval for plugs, wires, cap and rotor was every 30,000 miles. If you don't know when it was last done, do it now. Many times that simple maintenance stuff is the source of your problems.
Then, you're starting with something that is known, a baseline so to speak.
Then, you're starting with something that is known, a baseline so to speak.
Cruiser54 you know your stuff. A lot of your info has helped me. So what you say I'm doing!! Everyone can learn a lot from you. And I thank you for shareing your knowledge!!
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Really every 30,000?? So is buying all the big name brand stuff worth it?? And buying the life time warrenty parts?
Cruiser54 you know your stuff. A lot of your info has helped me. So what you say I'm doing!! Everyone can learn a lot from you. And I thank you for shareing your knowledge!!
Cruiser54 you know your stuff. A lot of your info has helped me. So what you say I'm doing!! Everyone can learn a lot from you. And I thank you for shareing your knowledge!!
Recommended time to replace the fuel filter, too.
Clean the throttle body and IAC are what we did on the 30,000 mile services also.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,579
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0