I just changed my spark plugs. Nothing fancy just copper champions and I drove her a little right after. Came to a stop light and noticed she was shaking a little heavier than normal. Don't know if it has anything to do with the change but I just noticed it now
CF Veteran
You either have a few wires crossed, damaged a few plug wires when pulling them off of the plugs, or the gap is screwed up on one or more plugs.
Seasoned Member
Also check to make sure your plug boots are seated all the way onto the plug ends. If one or more isn't seated all the way flush, it'll misfire.
rechecked everything, found out my #1 wasn't connected. Thank you guys for all your help and the speedy responses.
Member
Since you're in the "tune up mode" I'd also clean the throttle body and plate. Don't forget the backside of the throttle plate. Clean it with TB cleaner and a soft toothbrush and wipe it clean till it sparkles.
Seasoned Member
I recommend you seafoam it. My jeep had clean oil when i did and two days later when i changed it it was almost black. It also cleared out any metal in there too. Theres a noticable difference. I went all out with it. I put half a can in the oil, half in the brake booster vaccum tube and a whole can in the gas tank. I couldnt believe what it cleaned out. Since it ran for sometime with a non firing cylinder it would do some good. Just be prepared for the biggest cloud of smoke youve ever seen. Just make sure to change your oil after 30 to 50 miles and it will be as clean as new(ish).
::CF Moderator::
cruiser54
::CF Moderator::
close
May 16, 2024
- Join DateAug 2011
- LocationPrescott, Az
- Posts:43,971
- Year1990
- ModelCherokee (XJ)
- Engine4.0
-
Likes:1,979
-
Liked:1,578 Times in 1,279 Posts
--------------------------------------------------------------------
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
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
Seasoned Member
Cruiser54, i cleaned my iac recently and i was wondering if the pintel will return back where it should automatically once i run it? Reason i ask is because i turned it a little by accident due to the very hard deposits on it.
::CF Moderator::
cruiser54
::CF Moderator::
close
May 16, 2024
- Join DateAug 2011
- LocationPrescott, Az
- Posts:43,971
- Year1990
- ModelCherokee (XJ)
- Engine4.0
-
Likes:1,979
-
Liked:1,578 Times in 1,279 Posts
Hope for the best. Probably okay.