2002 TJII Sports 5 speed auto, sedan.

I've had this sound for a while now and thought it was something to do with transmission or sticky rear brakes (front are like new, haven't done rear yet).

BUT

Today I started my vehicle in park, hand brake off (foot on brake). About 1 or 2 seconds after the engine started there was this God almighty "crunch" sound. It seemed to be coming from the front left, but it's hard to be sure as sound can bounce around.

Only really does it when cold.

Any ideas? :ninja:

if its only when you start the car check your starter motor. or is it while the car is running?

guessing it could be a shit tooth on the flywheel also but id check the starter first

It happens a couple of seconds after the car is running. Could it still be starter related?

If it was a tooth on the fly wheel wouldn't it make the noise all the time?


if its only when you start the car check your starter motor. or is it while the car is running?

guessing it could be a shit tooth on the flywheel also but id check the starter first

I think i worked it out,... or at least what it is...

I had the misses start the vehicle this morning, whilst my head was under the bonnet. I am fairly certain it was the electric fan on the driver's side.

I haven't had time to explore it further, but am posting simply as an update.

I guess my next move will be to unplug the fan, start the vehicle and listen to determine if the noise has gone (to confirm it is the fan). The only problem is that the noise is intermittent and only on first starts when the vehicle has been sitting for some time (a day or two).

Has anyone experienced similar noise/fan issues?

Now I'm thinking starter motor bendix is not disengaging quickly enough from fly wheel on cold starts....

I found one for $85 delivered on Ebay. So should be a cheap fix if I do the work myself and it seems like a simple enough job.

If it is the starter, get someone to start the car while you listen with the bonnet up. A stuck starter will give you a definite high rev whine before it disengages.
If so - Perhaps take the starter out and test across a battery?

If it is the starter, get someone to start the car while you listen with the bonnet up. A stuck starter will give you a definite high rev whine before it disengages.
If so - Perhaps take the starter out and test across a battery?

I will try that this afternoon (when other half comes home) and video tape it. Hopefully it will make the noise.

It is intermittent, usually only making the noise when the car has been sitting for a couple of days. It's a crunching grinding noise lasting only 1 second or so directly after the car has been started. I thought it sounded like it was coming from one of the fans, but I'm not sure. I will disconnect the suspect fan today when I do the test and then try again with the fan connected.

I know Madmagna has talked about the belt pre tensioner (for similar noises), but my belts look fine (in that they don't appear to be wobbling because they are loose).

I will be sure to do an update (with video if it makes the noise).

http://youtu.be/5c1XIFSov98

There is a distinct noise at the 13 second mark. I had the fan unplugged, so definitely not the fan.

I thought maybe it could be the starter motor but now I'm thinking something else. Pre tensioner?

Opinions appreciated...

http://youtu.be/5c1XIFSov98

There is a distinct noise at the 13 second mark. I had the fan unplugged, so definitely not the fan.

I thought maybe it could be the starter motor but now I'm thinking something else. Pre tensioner?

Opinions appreciated...

Sounds like a loose belt which flops for a moment before getting traction. When did you last do the timing belt?

Sounds like a loose belt which flops for a moment before getting traction. When did you last do the timing belt?

Never. I've only had the vehicle since January (9 months). It has about 190,000km, so it is probably due for new a timing belt soon (assuming it was done at 100,000km).

Often this is the AC compressor, try starting with AC turned off

That's more of a clunk, and it is louder if the car hasn't been used for a few days, but yeah, there is a time delay between starting the car and the compressor engaging if you start the car with the A/C on.

That's more of a clunk, and it is louder if the car hasn't been used for a few days, but yeah, there is a time delay between starting the car and the compressor engaging if you start the car with the A/C on.

So would that mean I'd need to replace the whole compressor or maybe just the bearing,... or is it something I don't need to worry about?

Thank you to both Madmagna and MadMax for the info

That sounds very similar to a noise our old ralliart used to do....very rarely, didnt matter if the car was used daily or was left sitting for a bit

Only did it though when aircon was switched on before car was started, and the noise came at about the same time as yours does....

We never fixed it, as it was so few and far between, so cant help you there

Definately seemed aicon related

Not a problem. They just get noisier when the car ages.

Not a problem. They just get noisier when the car ages.

I can see compressors on Ebay for about $290. That plus labor and a regas I guess I'd be up for $500 to $600 to replace the new compressor.

...or put up with the noise.

Decisions decisions... :think:

It's not the compressor. It is the engagement clutch that makes the clunk. Do some research on how it works and you will see the noise is common/normal/harmless.