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-   -   Starting troubles (http://www.jeepforum.com/forum/f53/starting-troubles-1522050/)

djdr1988 05-11-2013 04:59 PM

Starting troubles
 
89 Jeep Comanche, i just replaced the distributor in my truck, it has the 4.0 L.
When i start it, it runs extremely rough at low rpms for a minute then dies. I have tried moving the wires on the cap and resetting the computer, but nothing seems to work. Anyone have any idea?

cruiser54 05-12-2013 06:37 AM

ECU doesn't reset. Timing can't be adjusted with the distributor.

Time to do a few things. First off, make sure your distributor is indexed correctly. see #13.
Make sure your intake manifold bolts aren't loose. How old are the plugs, wires, cap and rotor?

Clean your throttle body.

Courtesy of TJWalker:
--------------------------------------------------------------------
The Idle Air Control (IAC) is mounted on the back of the throttle body. (front for 87-90) The valve controls the idle speed of the engine by controlling the amount of air flowing through the air control passage. It consists of a stepper motor that moves a pintle shaped plunger in and out of the air control passage. When the valve plunger is moved in, the air control passage flows more air which raises the idle speed. When the valve plunger is moved out, the air control passage flows less air which lowers the idle speed. Over time and miles, the IAC can get carboned up which can have an adverse affect on idle quality. Cleaning the IAC may restore proper function and is an easy procedure to perform and good preventive maintenance so it is never a bad idea.

CLEANING THE JEEP 4.0 IDLE AIR CONTROL

Remove the air filter cover, associated hoses and the rubber boot that goes from the air filter cover to the throttle body. Remove the IAC with a torx driver (2 bolts; one can be kind of hard to get to)

“Gently” wiggle out the IAC from the throttle body. Gasket on the IAC can be re-used if it is not damaged

Clean the IAC with a spray can of throttle body cleaner; inexpensive and available at any place that sells auto parts. Throttle body cleaner is recommended rather than carburetor cleaner as it is less harsh, safe for throttle body coatings and is best for this task. Use cleaner, a rag and a toothbrush and or Q-Tips. Be gentle; don’t twist or pull on the pintle that protrudes from the IAC as it is fragile and you could damage it.

Thoroughly spray clean and flush where the IAC seats in the throttle body with the same spray cleaner

It is also a good idea to clean the entire throttle body itself, the butterfly valve inside of the throttle body and all associated linkage as long as you have things disassembled



Do 1,2,3, and 4, along with 13 in the folowing link. Cheap and easy.

http://www.cherokeeforum.com/f51/cru...x-tips-153657/

djdr1988 05-12-2013 09:41 AM

I have set the distributor correctly and it still does the same thing. I replaced the plugs, cap, and rotor with the distributor. The wires are only a few months old

cruiser54 05-12-2013 11:47 AM

How about the tips, and cleaning the throttle body?

djdr1988 05-12-2013 11:59 AM

Im waiting for a throttle body gasket. I have checked grounds and cleaned connections. It ran before i put this didtributor in. I replaced it because thebold one was full of oil under the cap and it had a long start issue i have been trying to figure out

cruiser54 05-12-2013 12:01 PM

Quote:

Originally Posted by djdr1988 (Post 15423451)
Im waiting for a throttle body gasket. I have checked grounds and cleaned connections. It ran before i put this didtributor in. I replaced it because thebold one was full of oil under the cap and it had a long start issue i have been trying to figure out

On a Renix it's easy to clean the TB withut removal. The IAC comes off easily.
HOs on the other hand are easier to do by removing them.

djdr1988 05-12-2013 12:28 PM

Its not an HO. I just spray throttle body cleaner into where the iac goes?

cruiser54 05-12-2013 12:57 PM

Quote:

Originally Posted by djdr1988 (Post 15423543)
Its not an HO. I just spray throttle body cleaner into where the iac goes?

Courtesy of TJWalker:
--------------------------------------------------------------------
The Idle Air Control (IAC) is mounted on the back of the throttle body. (front for 87-90) The valve controls the idle speed of the engine by controlling the amount of air flowing through the air control passage. It consists of a stepper motor that moves a pintle shaped plunger in and out of the air control passage. When the valve plunger is moved in, the air control passage flows more air which raises the idle speed. When the valve plunger is moved out, the air control passage flows less air which lowers the idle speed. Over time and miles, the IAC can get carboned up which can have an adverse affect on idle quality. Cleaning the IAC may restore proper function and is an easy procedure to perform and good preventive maintenance so it is never a bad idea.

CLEANING THE JEEP 4.0 IDLE AIR CONTROL

Remove the air filter cover, associated hoses and the rubber boot that goes from the air filter cover to the throttle body. Remove the IAC with a torx driver (2 bolts; one can be kind of hard to get to)

“Gently” wiggle out the IAC from the throttle body. Gasket on the IAC can be re-used if it is not damaged

Clean the IAC with a spray can of throttle body cleaner; inexpensive and available at any place that sells auto parts. Throttle body cleaner is recommended rather than carburetor cleaner as it is less harsh, safe for throttle body coatings and is best for this task. Use cleaner, a rag and a toothbrush and or Q-Tips. Be gentle; don’t twist or pull on the pintle that protrudes from the IAC as it is fragile and you could damage it.

Thoroughly spray clean and flush where the IAC seats in the throttle body with the same spray cleaner

It is also a good idea to clean the entire throttle body itself, the butterfly valve inside of the throttle body and all associated linkage as long as you have things disassembled

djdr1988 05-13-2013 12:23 PM

I got it running again. I had to pull the distributor back out and turn the engine 360 degrees and line up the oil pump for it to sit at the right timing

djdr1988 05-13-2013 12:24 PM

Thanks for all your help


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