I am hearing this hissing noise while my engine runs and I am trying to figure out where it’s coming from. Generally is this what vacuum leaks sound like? I also think it may be my throttle body.
Does this sound like a vacuum leak?
- Thread starter DropTopDon
- Start date
I can hear what sounds like the throttle body bringing in air and several fuel injectors pulsing, but I can not identifying a vacuum leak in that audio.
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OP
OP
This may be a dumb question but is it normal for it to be that loud when the throttle body is bringing in air? I can hear it clearly from inside the car while driving. It was not like that prior to me cleaning the IAC. I put everything back together correctly and everything is tight.
If there is no obvious leak from the valve cover, you may have some leaking injector O-rings. Do you smell gas?
While you might hear a slight intake air sound while idling; it is doubtful you would hear it from inside the Jeep.
Ensure the intake air tube is seated properly onto the throttle body throat and the clamp is snug.
If this noise occurred after the cleaning of the IAC; then I would inspect how the solenoid body is seated into the throttle body.
Are the engine RPMs higher than normal ?
OP
The RPMS while the jeep idles fluctuate, sometimes they will go up and sometimes they will go down but usually they are on the lower side (why I cleaned the IAC). This is part of the frenzy I have been going through trying to fix my jeep.
DropTopDon, did you find a solution for this noise? My 2001 started making the same things this morning.
OP
I did. A small rubber elbow fitting had popped off on the side of the intake manifold. I just slid it back on and it fixed it. I will take a picture when I can
That makes sense, I had a small pop as I started it and the instantly had that noise. I didn't have time to look at it but I recognized it in your video as soon as I heard it. I will check it out tonight! Thanks!
I just found this old thread, hoping someone will see my reply here, this just happened with my 2002 TJ, and I'm hoping someone can help me pinpoint where to check for this elbow fitting that solved the problem. @DropTopDon?
On the side of the intake manifold...drivers side... probably just in front of the brake booster, master cylinder.
-Mac
Thank you! Sure enough, that's what it was and I found it pretty easily, popped it back on and so far so good!