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duke183
July 21st, 2010, 05:58
I have a 2000 xj sport 4.0L with 100k miles. 4x4. Anyway, I am getting a chirping in the engine bay when I first start up the car for about 10 minutes. It is not related to AC because it does it whether the ac is on or off. It does make the noise in park and in gear, again for the first ten minutes and then goes away.

It is definitely a chirping and not a squeel. I had the squeel before and that was awful, had the serp belt replace about 10 months ago and the idler pulley. Then in February the power steering pump blew up and spray fluid everywhere. The shop I took it to said they cleaned off the belt and it should be fine so they just put it back on.

What do you guys think this could be. I know I have a lot of noises in my Jeep, and I can deal with most of them but the high pitch chirping and squeeling are too much.

On top of all that, I don't want to take it back to another mechanic only to pay a ton of money in labor again.

Thanks!

duke183
July 21st, 2010, 07:40
Please help.

heyhar
July 21st, 2010, 07:48
Serpentine belt. Doesn't have to be slipping. I've tried 'em all, and as has been suggested on this board, use only Gates or Goodyear Gatorback brands. I've got Gates on both of mine, and chirping is one noise I DON'T hear! I had to go to NAPA to get them. While you're there, pick up a Krikit (sp), to set the tension properly. Don't mess with any other belts.

hightime81
July 21st, 2010, 07:55
can you specify a little more on where it is coming from? a chirp sound especially near the AC compressor might signal worn compressor bearings.

does it get faster when the engine is revved?

duke183
July 21st, 2010, 08:09
It does get faster when the engine is revved. And not sure if it matters but turning the ac on or off makes no difference on whether it makes the noise on start up.

hightime81
July 21st, 2010, 08:24
can you be a little more specific on where the sound is coming from? if it is the engine itself? or if it is the front of the engine (pulley's)?

if its the front of the engine, that sounds like a pulley to me. Could be as simple as the belt being over-tightened and it's putting too much strain on the pulley's. could be the water pump giving up the ghost.

the more details you can give on where it is, the more we can probably help!

good luck!

duke183
July 21st, 2010, 08:25
Sorry, thanks. IT does sound like it is coming from the front...pulleys/belts. Somewhere up there. Mainly to the front driver's side.

.40CalPatriot
July 21st, 2010, 08:26
Check the idler pulley and the harmonic balancer.

hightime81
July 21st, 2010, 08:37
along with checking those pulleys purchase a kriket 2 ($20 i think) from Napa and use it to establish the belt tension to ensure you have the correct tension on it. if it's too tight it can damage components and chirp. if its too loose it can slip.

duke183
July 21st, 2010, 08:40
How do I check those, by removing the belt and then trying to wiggle them?

hightime81
July 21st, 2010, 08:46
for the water pump pulley yes. in fact depending on belt tension you should be able to give it a shot with the belt on.

other than that, according to my FSM, you should check the pulleys for any kind of nicks/cracks/corrosion that could affect operation.

PhotographerMike
July 21st, 2010, 08:59
The harmonic balancer could be separating, the outer part can get out of alignment with the rest of the pulleys and chirp and be very hard to track down.
Happened to my '89 and I replaced almost every rotating part before I "discovered" the ballancer.
Pour a little water on the belt and see if the chirp goes away for a bit, that will help eliminate bad bearings.

It's difficult to get the belt too tight.

2X on the Kriket 2 and Gatorback belts.

duke183
July 21st, 2010, 10:38
Gotcha, sounds good. Looks like I have some ideas. Thanks everyone!

joe_peters
July 21st, 2010, 13:24
You want to find the source of the noise?

Purchase 3' of vinyl tubing (any hardware, most auto parts stores), 1/2" or less I.D. Stick one end in your ear, then move the other end around the engine when it is making the noise--CAUTION ABOUT MOVING ENGINE PARTS AND CLOTHING/FLESH--you WILL be able to isolate the sound, then you can take the appropriate action.

Once a belt has been contaminated they don't always "clean up", and a couple of contaminated areas can lead to some weird sounds as they travel around the pulleys.

duke183
July 21st, 2010, 14:42
Joe peters, thanks for that info. I will do this. They warned me about the belt, but they were trying to save me money in not replacing it. However, after I looked it up...doesn't seem to difficult to replace. So, I think I will by the tubing, listen in, and then let you know.

Thanks again.

Begster
July 21st, 2010, 14:50
Check the passenger side by the fire wall, around where the heater hoses go through the firewall. If I remember correctly, it is either a little black piece, or a piece with a green cover, its a valve I believe for the emissions stuff. It is pretty normal, you should actually feel it. My '99 does this as well.

I'll see if I can grab a picture of it next time I'm at my Jeep.

joe_peters
July 21st, 2010, 16:13
Check the passenger side by the fire wall, around where the heater hoses go through the firewall. If I remember correctly, it is either a little black piece, or a piece with a green cover, its a valve I believe for the emissions stuff. It is pretty normal, you should actually feel it. My '99 does this as well.

I'll see if I can grab a picture of it next time I'm at my Jeep.

Your thinking of the EVAP purge solenoid? More of a constant "ticking" noise, but doesn't hurt to listen to it.

Begster
July 21st, 2010, 17:00
Yep, I was thinking of the EVAP purge solenoid, just couldn't get it off my tongue.

Hmm, I know I definitely had a chirping noise when I picked up my '99 5 years ago, but I can't seem to remember what it was, or even if it still is present.

muddypunk
July 22nd, 2010, 09:38
I had this problem on 95 and I used hose to find general area of nosie ended up wire brushing and swashing all of my pulleys I also try not to go headlight deep in mud any more.My noise was gone after I put new belt on and cleaned pulleys.And alt was packed full of mud had to clean it as well

nofender
July 22nd, 2010, 12:47
I had the same annoying chirp. I replaced idler - no change. Turned out to be the cheap ass serp belt i had bought. Changed to a quality one and it was gone.