• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

2001 4.0 sounds like a tea kettle in cold temps

I have the Rusty's intake tube and a bored TB, which both make whistles/noises that i know and i'm familiar with. My problem noise isn't like these either...

The funny thing is that i hear 4.0 WJs driving around with the same noise from time to time, so i'm led to believe it's something specific to this drivetrain.

I think i've narrowed it down to something transmission related, based on my previous posts, but that's where i'm lost? Could a slightly overfilled transmission have anything to do with it?
 
Last edited:
I am almost sure that it is one of the front wheel bearings now. I'm assuming those are sealed and not grease-able at all? Is this just a ticking time bomb now? I have no grinding or similar noises usually associated with failing wheel bearings...
 
Cool weather and the tea kettle is back!

I wanted to bump this in case anyone else had experienced a similar issue and fixed the problem :)
 
This thread needs some serious clarification. Does it make the noise at all in park at any engine speed? Or just while the jeep is being driven?
 
I've elaborated on that in the first pages, but this thread is so old I'll repost:

It's a constant high-pitched whistle (literally like a tea kettle) that only occurs when in drive and moving. It doesn't become audible (at least to me in the cabin) until roughly 15-20 mph. It doesn't make the noise when revved in park/neutral.

The last part is what makes it damn near impossible to diagnose. One thing I know for sure: it is not driveshaft related.
 
Brakes dragging?
 
Is it possible that lube pressure in front diff is building up at speed and cold temps are freezing up the vent cap causing a whistling noise?

Just a wild ass guess, but you could pull the vent cap and see if it goes away.
 
Wild Guess,,,,, your 2001 has a coil on plug system and has No plug wires. But you still have an "oil pump drive assm. that contains the cam sensor..this looks like the distributor without the cap & wires.
Could this be going bad ? Later model TJ,s with the 4.0 engine had this assm seize up and cause all kinds of problems.
 
You should take a video of your jeep driving by at whatever the speed is it starts whistling, or have a passenger take video of you driving by a wall passenger side. I havent had a problem like this, but it makes me curious if nobody has figured it out in two years.

So you say it does it when its cold outside in general? Or when the jeep is not at operating temp?

Edit: I did some google searching and found out a lot of people replaced intake manifold gaskets and it went away, they said it was blown out on the firewall side... i know the thread said you torqued the bolts down, but if the gaskets already gone its not going to help... i do have a whistle, but it know its the throttle body with my intake, and its when I crack the throttle about 1/5 open
 
Last edited:
Thanks for the suggestions. The vent tube idea never occurred to me before, easy to try. The oil pump drive assembly problem was specific to the 05/06 TJs, but that seems like something I wouldn't know about until it happened. Thanks for the suggestion.

Breezio69 said:
You should take a video of your jeep driving by at whatever the speed is it starts whistling, or have a passenger take video of you driving by a wall passenger side. I havent had a problem like this, but it makes me curious if nobody has figured it out in two years.

So you say it does it when its cold outside in general? Or when the jeep is not at operating temp?

Edit: I did some google searching and found out a lot of people replaced intake manifold gaskets and it went away, they said it was blown out on the firewall side... i know the thread said you torqued the bolts down, but if the gaskets already gone its not going to help... i do have a whistle, but it know its the throttle body with my intake, and its when I crack the throttle about 1/5 open
Click to expand...

When it's cold outside in general. I've done extensive searching on this and I've seen where people have replaced the gasket and fixed the noise, but the thing that throws me is that my noise doesn't occur when stationary. I would think a manifold leak would cause a noise regardless...

Luckily, at least from what I can tell, this doesn't effect how my Jeep runs
 
You don't have any of those deer whistles on your vehicle, do you? It sounds to me like it could be a wind whistle like on a loose piece of body trim or a roof rack. It seems as though you never hear it at idle or slow speeds but as your speed increases over 20 mph, you hear it. It only shows up during cold weather so there is something that is quiet in warm weather then shrinks in space/size as it gets colder. I would go purchase a roll of that blue painters tape and tape up every nook and cranny and drive it. if it goes away, start removing individual pieces of tape until you hear it again. I'd almost guarantee that is your problem.
 
How did you make out on this problem?
 
I'm still living with it. I'm almost positive that it's something rotational at this point, but I still haven't had a chance to put it on a lift and listen for the point of the noise.

I don't have any grinding noises or any of those bad u-joint noises (been there, done that). Given how loud the noise is, I think I can rule out any whistling trim pieces (no deer whistles either). I've experienced whistling trim pieces on a previous car.

The other morning it was 10* out and the noise was the loudest I've ever heard it. I do need to replace my power steering pump very soon, so I'm hoping (fingers crossed) the noise is related to that.
 
I would try narrowing it down a little. Do this, in a wide open area, put the jeep up on 4 jack stands with the tires off of the ground. Make sure it is very stable. Start engine, put it in drive (2 wheel drive) and bring it up to the speeds that you normally hear it. Then put it in 4 wheel High and try it again.

1- If you don't hear it at all in either instance, it might be wind related. Or it could be a front bearing assembly (unit bearing)and might need the weight of the vehicle on it to make the sound but I don't think it would be this as usually, it would make some sort of sound at all speeds.

2- If you hear it in 2 wheel drive, it's in the drivetrain or rear axle. Might also be a pinched tranny cooler hardline or a degrading tranny cooler flex line (sometimes the inner part of the flex line starts do disintegrate with age) or something in the tranny. (you mentioned that if you change the gear selector from drive to neutral, the sound stops for a moment. This is assuming that you were at speed)

3-If you don't hear it in 2 wheel but hear it in 4 wheel drive, it's probably somewhere in the front drive shaft or front axle.

Let us know what you find.
 
You must log in or register to reply here.

Similar threads

I
High idle, smells like gas, running out of things to replace
Replies
2
Views
2K
Inverhyt
I
S
98 A/C resurrection
Replies
15
Views
3K
XJlimitedx99
X
F
Drum Brake Damage - Post mortem?
Replies
16
Views
3K
RCP Phx
R
C
Ticking/Knock/Rattle that matches RPM 88 XJ
Replies
13
Views
2K
PacificEd
PacificEd
S
Torque converter causing low rpm engine lope
Replies
2
Views
2K
lawsoncl
L
Back
Top