Hi all. Here's the story:
I've only had my 2004 TJ for about a week or so. I purchased it used from a dealer, and overall it runs well. Drove it this morning, all was good. Several days ago, she did something weird: She whistled. Not a small whistle, oh no, but a large all out steam kettle scream. But only while idling.
I started her up to go get a haircut. I left my house, and about a mile down the road, the whistling started - I noticed it when I let my foot off the gas to brake. Accelerating made the whistle go away. But at idle - when braking and stopped - she whistled loudly. I pulled over, opened the hood, and could plainly hear that the whistle seemed to be coming from the throttle body. I felt around the area, probing here and there with my fingers, and it felt like (which at the time I didn't know what part it was, but I learned later) the IAC valve was vibrating with the whistle.
As I sat there probing, the whistle died down, and stopped. I never heard it again the rest of the day. I got my haircut, came back out, started her up, drove her home, and no whistle.
The next day I drove her to work - and the same thing happened. Same order. I parked her, got out - still seemed like the TB/IAC. I tried tightening down the intake hose (from the air filter) - that didn't change anything, and I had no other tools to try anything else. Eventually the sound went away, I went to work, and when I drove home, no issue.
The next time I drove her to work, it happened again, so I stopped at a pep boys and got some TB cleaner and hosed it down on the inside (there was a bit of crud) - I also tried to get it as much as possible into the ports to the IAC. Put it back together, no more noise, and no noise when I came home.
I did some research - everything I read seemed to indicate to clean the throttle body, and IAC valve, etc. I purchased a new TB gasket, and yesterday set to work. I got everything cleaned nice and shiny. When I went to clean the IAC, I decided to do the housing as well. I took it off the TB - and the gasket in between kinda crumbled apart as I separated the pieces. "Aha!" so I thought - likely that gasket was bad. Unfortunately, I didn't have a replacement gasket, but I went ahead and cleaned everything. Then I took the TB and a piece of paper, and "rubbed" with a pencil the outline of the housing opening, and then glued that to a piece of thin cereal box cardboard. I used an x-acto knife and cut out a gasket, then sandwich'd that between the parts, and tightened the housing back on. I then mounted the clean IAC valve (with a new o-ring), and put everything back together. I started her up, she ran well - like normal, maybe a bit better.
Later that evening I went to the store. She ran fine there and back, no noise or anything. This morning I went out to go to a friend's house; on the way there, she started whistling! I stopped in a parking lot, lifted the hood, felt around the TB and IAC - nothing seemed out of place, but the whistling was there. After a few minutes, she quieted down - I drove to my friend's house, we went hiking for a couple of hours, and I drove around - but no more whistling. Before I came home, though, I went to AutoZone and bought a new IAC valve, figuring that might be the next step.
I came home, disconnected the battery (I have a battery disconnect), installed it, and started her up - and I had a high idle - close to 2k RPM. I tried "goosing" the throttle, that only boosted it up to 3k and never went down. I also noticed the CEL on, but I didn't have a code reader handy to check the code. I tried multiple shutdowns and starts - but still the high idle and CEL. I tried to "reset" the computer by touching the positive cable (pulled from the battery) to the negative. Still a high idle and CEL. I disconnected the battery, and came inside to post this small book you are reading.
Ideas? Suggestions? What I plan to try next:
1. Go back out there, and make sure the intake manifold is tightened down properly. Maybe there's a vacuum leak there? If it is a bad intake manifold gasket, that may or may not help - but it's worth a shot; I don't have the time to do anything deep on this engine right now.
2. Then try starting her up, and see if that helped and/or if letting her sit "unplugged" for the last 20 minutes or so has helped anything. I doubt it, but we'll see.
3. I'll try spraying the TB cleaner around the throttle body and gaskets, etc - to see if the idle changes - vacuum leak? Maybe also around the vac lines from the brake booster and PCV (or whatever it is)...
4. If that fails, then I'll chock the wheels, put 'er in gear, and see if adding a load helps anything.
5. If that fails - well, I'll be at a loss. I'll probably try to re-install the old IAC valve and see if that changes anything.
One last thing: I noticed on the new IAC valve that the "pintle shaft" seemed longer than the original IAC valve shaft. The original one had a "sleeve" that could be retracted, but the actual "pintle shaft" couldn't be moved on either one (or so it appeared - I didn't try very hard to move them). The "sleeve" on the new IAC valve didn't move at all, though. To be honest, I can't even see how this valve is supposed to work; it appears that it should be like a valve that moves in and out and "seals" the difference in air between the upper and lower parts of the TB - bypassing the butterfly flap valve. But it doesn't move (like you'd expect a solenoid to move) - unless its some kind of small linear actuator motorized thing?
Ok - if you've read this far, I thank you. I know this has been a very long post, but I wanted to make sure I covered everything I've done or tried - I hope it helps, and I hope someone out there can assist me. Otherwise, she'll probably be taken to my mechanic - I seriously can't stand that damn whistling - of all the things to be "broken" on this vehicle as a used vehicle - I wish it'd happened when I test drove it. But of course, it didn't.
I've only had my 2004 TJ for about a week or so. I purchased it used from a dealer, and overall it runs well. Drove it this morning, all was good. Several days ago, she did something weird: She whistled. Not a small whistle, oh no, but a large all out steam kettle scream. But only while idling.
I started her up to go get a haircut. I left my house, and about a mile down the road, the whistling started - I noticed it when I let my foot off the gas to brake. Accelerating made the whistle go away. But at idle - when braking and stopped - she whistled loudly. I pulled over, opened the hood, and could plainly hear that the whistle seemed to be coming from the throttle body. I felt around the area, probing here and there with my fingers, and it felt like (which at the time I didn't know what part it was, but I learned later) the IAC valve was vibrating with the whistle.
As I sat there probing, the whistle died down, and stopped. I never heard it again the rest of the day. I got my haircut, came back out, started her up, drove her home, and no whistle.
The next day I drove her to work - and the same thing happened. Same order. I parked her, got out - still seemed like the TB/IAC. I tried tightening down the intake hose (from the air filter) - that didn't change anything, and I had no other tools to try anything else. Eventually the sound went away, I went to work, and when I drove home, no issue.
The next time I drove her to work, it happened again, so I stopped at a pep boys and got some TB cleaner and hosed it down on the inside (there was a bit of crud) - I also tried to get it as much as possible into the ports to the IAC. Put it back together, no more noise, and no noise when I came home.
I did some research - everything I read seemed to indicate to clean the throttle body, and IAC valve, etc. I purchased a new TB gasket, and yesterday set to work. I got everything cleaned nice and shiny. When I went to clean the IAC, I decided to do the housing as well. I took it off the TB - and the gasket in between kinda crumbled apart as I separated the pieces. "Aha!" so I thought - likely that gasket was bad. Unfortunately, I didn't have a replacement gasket, but I went ahead and cleaned everything. Then I took the TB and a piece of paper, and "rubbed" with a pencil the outline of the housing opening, and then glued that to a piece of thin cereal box cardboard. I used an x-acto knife and cut out a gasket, then sandwich'd that between the parts, and tightened the housing back on. I then mounted the clean IAC valve (with a new o-ring), and put everything back together. I started her up, she ran well - like normal, maybe a bit better.
Later that evening I went to the store. She ran fine there and back, no noise or anything. This morning I went out to go to a friend's house; on the way there, she started whistling! I stopped in a parking lot, lifted the hood, felt around the TB and IAC - nothing seemed out of place, but the whistling was there. After a few minutes, she quieted down - I drove to my friend's house, we went hiking for a couple of hours, and I drove around - but no more whistling. Before I came home, though, I went to AutoZone and bought a new IAC valve, figuring that might be the next step.
I came home, disconnected the battery (I have a battery disconnect), installed it, and started her up - and I had a high idle - close to 2k RPM. I tried "goosing" the throttle, that only boosted it up to 3k and never went down. I also noticed the CEL on, but I didn't have a code reader handy to check the code. I tried multiple shutdowns and starts - but still the high idle and CEL. I tried to "reset" the computer by touching the positive cable (pulled from the battery) to the negative. Still a high idle and CEL. I disconnected the battery, and came inside to post this small book you are reading.
Ideas? Suggestions? What I plan to try next:
1. Go back out there, and make sure the intake manifold is tightened down properly. Maybe there's a vacuum leak there? If it is a bad intake manifold gasket, that may or may not help - but it's worth a shot; I don't have the time to do anything deep on this engine right now.
2. Then try starting her up, and see if that helped and/or if letting her sit "unplugged" for the last 20 minutes or so has helped anything. I doubt it, but we'll see.
3. I'll try spraying the TB cleaner around the throttle body and gaskets, etc - to see if the idle changes - vacuum leak? Maybe also around the vac lines from the brake booster and PCV (or whatever it is)...
4. If that fails, then I'll chock the wheels, put 'er in gear, and see if adding a load helps anything.
5. If that fails - well, I'll be at a loss. I'll probably try to re-install the old IAC valve and see if that changes anything.
One last thing: I noticed on the new IAC valve that the "pintle shaft" seemed longer than the original IAC valve shaft. The original one had a "sleeve" that could be retracted, but the actual "pintle shaft" couldn't be moved on either one (or so it appeared - I didn't try very hard to move them). The "sleeve" on the new IAC valve didn't move at all, though. To be honest, I can't even see how this valve is supposed to work; it appears that it should be like a valve that moves in and out and "seals" the difference in air between the upper and lower parts of the TB - bypassing the butterfly flap valve. But it doesn't move (like you'd expect a solenoid to move) - unless its some kind of small linear actuator motorized thing?
Ok - if you've read this far, I thank you. I know this has been a very long post, but I wanted to make sure I covered everything I've done or tried - I hope it helps, and I hope someone out there can assist me. Otherwise, she'll probably be taken to my mechanic - I seriously can't stand that damn whistling - of all the things to be "broken" on this vehicle as a used vehicle - I wish it'd happened when I test drove it. But of course, it didn't.