Post by fivendime on Oct 16, 2009 16:31:04 GMT -8
This is a simple task but a very necessary task for a higher mileage vehicle. This cleaning will pertain to most IAC Valves. Some will have removable sections like this one and others like Ford ones don't. The IAC Vavle gets carbon-ed up and fails to work very well if at all over time. This leads to rough idle while warm or cold, surging, bucking, high idle etc. Its a simple but easy way to try to salvage the part which is in the range of 50 bucks and up. I will run you through a simple breakdown and part diagram so you can attempt this yourself.
Step one is to take the throttle body off the intake manifold using a 10mm socket. I do this so I can clean the throttle body as well as the IAC Valve, that way you can rule out the throttle body sticking which would also cause high idle that you can kick down with a stab of the throttle.
This is a shot of the TB (Throttle Body) off of the intake on a standard Jeep 4.0L.
This would be the TB as a whole. The far right black box is the Intake Manifold Pressure Sensor or for short MAP Sensor. The black box directly to the top in the center is the Throttle Position Sensor or TPS for short. The other black box to the top left is the IAC Valve, which is what we will be taking apart to clean.
After you have familiarized yourself with all the parts you will first take off the MAP Sensor by taking out the two T25 torx screws out and pulling till you pull the rubber boot off the nipple on the TB case. Notice how dirty and carboned up this TB is, I don't drive it like a grandma either!
Next you want to take off the first part of the IAC Valve buy removing two T20 torx screws. You may or may not be able to re-use the O-Ring that is between the two parts. Just keep that in mind. If you dont want to risk it leave this part attached and go to the next step, but it is highly recommended you clean this part as well.
After you have removed the IAC Vavle solenoid, you will want to remove the part that was attaching it to the TB case. This requires the use of a T20 torx security bit in this case. Be careful of the old gasket to not damage it while removal and cleaning.
Once you have all the parts off put the MAP Sensor aside. Take some THROTTLE BODY cleaner NOT carb cleaner unless its a product that is suitable for both, but it must say Throttle Body Cleaner as a use. Take a small tooth brush from the person you wish.....just not yours....haha. Holding the TB with the TPS in the UPRIGHT position clean as much of the carbon off as possible. This is to keep any cleaner and junk out of the TPS sensor. It may take several times and quite a few minutes for the job, but the more cleaner is it the better it will work. You may also have to soak the product, just DON'T submerge the TPS sensor. Sorry for all the yelling!
You can then Clean the IAC Valve by holding it with the point down and plug up. DO NOT submerge the IAC solenoid, just clean it with a toothbrush and clean towel.
You can also clean the other part that was connected to the IAC Valve solenoid. Remember to keep that gasket in tact, so be gentle. In other words don't take it to the sandblaster for cleaning........
This is a shot of all the parts clean and ready to put back together. Notice how much cleaner the TB is then it was before. Your other parts are now that much cleaner and ready for service.
You can then reverse the steps to put it back together. Before you put the torx screws back in dab a tiny drop of Thread Locker onto the threads to keep things in place. Then put the throttle body back on. Before you start it let the parts DRY completely before starting the vehicle back up. As long as you can wait is my rule, or at least wipe off dry and let stand for an hour or so.
Hope this helps!
Step one is to take the throttle body off the intake manifold using a 10mm socket. I do this so I can clean the throttle body as well as the IAC Valve, that way you can rule out the throttle body sticking which would also cause high idle that you can kick down with a stab of the throttle.
This is a shot of the TB (Throttle Body) off of the intake on a standard Jeep 4.0L.
This would be the TB as a whole. The far right black box is the Intake Manifold Pressure Sensor or for short MAP Sensor. The black box directly to the top in the center is the Throttle Position Sensor or TPS for short. The other black box to the top left is the IAC Valve, which is what we will be taking apart to clean.
After you have familiarized yourself with all the parts you will first take off the MAP Sensor by taking out the two T25 torx screws out and pulling till you pull the rubber boot off the nipple on the TB case. Notice how dirty and carboned up this TB is, I don't drive it like a grandma either!
Next you want to take off the first part of the IAC Valve buy removing two T20 torx screws. You may or may not be able to re-use the O-Ring that is between the two parts. Just keep that in mind. If you dont want to risk it leave this part attached and go to the next step, but it is highly recommended you clean this part as well.
After you have removed the IAC Vavle solenoid, you will want to remove the part that was attaching it to the TB case. This requires the use of a T20 torx security bit in this case. Be careful of the old gasket to not damage it while removal and cleaning.
Once you have all the parts off put the MAP Sensor aside. Take some THROTTLE BODY cleaner NOT carb cleaner unless its a product that is suitable for both, but it must say Throttle Body Cleaner as a use. Take a small tooth brush from the person you wish.....just not yours....haha. Holding the TB with the TPS in the UPRIGHT position clean as much of the carbon off as possible. This is to keep any cleaner and junk out of the TPS sensor. It may take several times and quite a few minutes for the job, but the more cleaner is it the better it will work. You may also have to soak the product, just DON'T submerge the TPS sensor. Sorry for all the yelling!
You can then Clean the IAC Valve by holding it with the point down and plug up. DO NOT submerge the IAC solenoid, just clean it with a toothbrush and clean towel.
You can also clean the other part that was connected to the IAC Valve solenoid. Remember to keep that gasket in tact, so be gentle. In other words don't take it to the sandblaster for cleaning........
This is a shot of all the parts clean and ready to put back together. Notice how much cleaner the TB is then it was before. Your other parts are now that much cleaner and ready for service.
You can then reverse the steps to put it back together. Before you put the torx screws back in dab a tiny drop of Thread Locker onto the threads to keep things in place. Then put the throttle body back on. Before you start it let the parts DRY completely before starting the vehicle back up. As long as you can wait is my rule, or at least wipe off dry and let stand for an hour or so.
Hope this helps!