running rough
nova2dr
01-04-2006, 07:55 PM
Hi all,
I have a 89 jeep cherokee 4wd 4.0. The # 5 injector was leaking so I took the rail and injectors apart, and notice that # 5 and 6 injector looked to be stopped up. So I changed those two and put new seals on the remaining 4 and the pressure regulator. ( It had run find with the leaking injector) .
I put everything back together and cracked her up and it really runs rough. I then changed the spark plugs and no differants. Sprayed all the vacum hoses with WD40 and there seems to be no leaks. I can tell it is running way to rich ( black smoke)
I'm wondering if those two cylinders were firing before, but like I said it was running fine. I haven't tried any top engine cleaner yet. I have no check engine light on either, I'm assuming the bulb is blown.
The old saying is " fix one thing two more things go bad ".
Thanks for any help and sorry for the long post.
I have a 89 jeep cherokee 4wd 4.0. The # 5 injector was leaking so I took the rail and injectors apart, and notice that # 5 and 6 injector looked to be stopped up. So I changed those two and put new seals on the remaining 4 and the pressure regulator. ( It had run find with the leaking injector) .
I put everything back together and cracked her up and it really runs rough. I then changed the spark plugs and no differants. Sprayed all the vacum hoses with WD40 and there seems to be no leaks. I can tell it is running way to rich ( black smoke)
I'm wondering if those two cylinders were firing before, but like I said it was running fine. I haven't tried any top engine cleaner yet. I have no check engine light on either, I'm assuming the bulb is blown.
The old saying is " fix one thing two more things go bad ".
Thanks for any help and sorry for the long post.
oljeeptek
01-04-2006, 09:54 PM
I would first check to see that the map sensor hose is hooked up correctly to manifold vacuum.
Then check to see that no injector wires got pinched.
Make sure the coolant sensor is still plugged in.
Where are the replacement injectors from? Are they the correct ones?
Do you have a fuel pressure guage to see if the injector(s) and regulator are not leaking into the engine?
Then check to see that no injector wires got pinched.
Make sure the coolant sensor is still plugged in.
Where are the replacement injectors from? Are they the correct ones?
Do you have a fuel pressure guage to see if the injector(s) and regulator are not leaking into the engine?
nova2dr
01-04-2006, 10:42 PM
I would first check to see that the map sensor hose is hooked up correctly to manifold vacuum.
Then check to see that no injector wires got pinched.
Make sure the coolant sensor is still plugged in.
Where are the replacement injectors from? Are they the correct ones?
Do you have a fuel pressure guage to see if the injector(s) and regulator are not leaking into the engine?
They are from advance... The engine was overhauled 4 or 5 years ago and the first 4 injectors were replaced then, they looked ok when I inspected them... I don't have a gauge but I was going to try and borrow one... I'll recheck the injector wires and I'll recheck the map sensor hose, I did have to replace it, the other one was dry rooted... I'm just wondering if the computer compensated for some things not being right over a long period of time... This is the first problems I've had in awhile.
Thanks for your responce.
Then check to see that no injector wires got pinched.
Make sure the coolant sensor is still plugged in.
Where are the replacement injectors from? Are they the correct ones?
Do you have a fuel pressure guage to see if the injector(s) and regulator are not leaking into the engine?
They are from advance... The engine was overhauled 4 or 5 years ago and the first 4 injectors were replaced then, they looked ok when I inspected them... I don't have a gauge but I was going to try and borrow one... I'll recheck the injector wires and I'll recheck the map sensor hose, I did have to replace it, the other one was dry rooted... I'm just wondering if the computer compensated for some things not being right over a long period of time... This is the first problems I've had in awhile.
Thanks for your responce.
oljeeptek
01-06-2006, 01:33 AM
They are from advance... The engine was overhauled 4 or 5 years ago and the first 4 injectors were replaced then, they looked ok when I inspected them... I don't have a gauge but I was going to try and borrow one... I'll recheck the injector wires and I'll recheck the map sensor hose, I did have to replace it, the other one was dry rooted... I'm just wondering if the computer compensated for some things not being right over a long period of time... This is the first problems I've had in awhile.
Thanks for your responce.
Renix ecu doesn't have much of a memory. It's rather senile actually. Ie it forgets everything when you keoy down after the latch relay shuts down.
A couple more things come to mind...
If it smokes and is rough at idle, but ok on the road you may have a closed iac stepper valve.
If its all speeds, you also may have a bad/loose/missing ground for the coolant, tps and map sensor curcuits.
Thanks for your responce.
Renix ecu doesn't have much of a memory. It's rather senile actually. Ie it forgets everything when you keoy down after the latch relay shuts down.
A couple more things come to mind...
If it smokes and is rough at idle, but ok on the road you may have a closed iac stepper valve.
If its all speeds, you also may have a bad/loose/missing ground for the coolant, tps and map sensor curcuits.
nova2dr
01-06-2006, 05:49 PM
Renix ecu doesn't have much of a memory. It's rather senile actually. Ie it forgets everything when you keoy down after the latch relay shuts down.
A couple more things come to mind...
If it smokes and is rough at idle, but ok on the road you may have a closed iac stepper valve.
If its all speeds, you also may have a bad/loose/missing ground for the coolant, tps and map sensor curcuits.
Thanks for your suggestions. It's rough at idle and going down the road, hopefully I'll be able to work on it Sat.
The sentence after (It's rather senile actually), please explain further.
I'll let you know how it turns out ......Thanks again!!
A couple more things come to mind...
If it smokes and is rough at idle, but ok on the road you may have a closed iac stepper valve.
If its all speeds, you also may have a bad/loose/missing ground for the coolant, tps and map sensor curcuits.
Thanks for your suggestions. It's rough at idle and going down the road, hopefully I'll be able to work on it Sat.
The sentence after (It's rather senile actually), please explain further.
I'll let you know how it turns out ......Thanks again!!
nova2dr
01-08-2006, 09:21 PM
Thanks for your suggestions. It's rough at idle and going down the road, hopefully I'll be able to work on it Sat.
The sentence after (It's rather senile actually), please explain further.
I'll let you know how it turns out ......Thanks again!!
Just an update...She is running fine now....I checked all my connections and everything looked ok. I was getting to much gas into the cylinders, flooding out like a carb...The pressure regulator checked good...So a friend suggested that I disconnect the battery, which I did when I replaced the injectors....But he said the system may need to reset itself, so I did for about ten minutes, hooked it back up and still the same thing. I let it sit for a few more minutes, she cracked up and is running smooth.
Thanks
The sentence after (It's rather senile actually), please explain further.
I'll let you know how it turns out ......Thanks again!!
Just an update...She is running fine now....I checked all my connections and everything looked ok. I was getting to much gas into the cylinders, flooding out like a carb...The pressure regulator checked good...So a friend suggested that I disconnect the battery, which I did when I replaced the injectors....But he said the system may need to reset itself, so I did for about ten minutes, hooked it back up and still the same thing. I let it sit for a few more minutes, she cracked up and is running smooth.
Thanks
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