I know this is a vague question since you guys can't hear it but I'll throw it out there for any opinions/ideas that you have. Well, I've got a 95 auto 4Runner 4x4. When I'm accelerating at slow speeds, for example taking off up to about 30 mph I can hear a whirring/whining sound. If the radio is on I can't hear it. My tranny shifts fine and as far as I can tell is ok. It sounds like it's coming the engine compartment. I had my headgasket, timing belt, water pump replace 4k miles ago and it's been doing since then. I'm thinking maybe it's my idler bearing since that was not replaced? Any ideas would be great. I've been living with this for the past few months and it hasn't gotten any louder but I'm still curious as to what it could be.

 

Yea, I know it's probably nothing to worry about. I was just kind of fishing for ideas about what a low pitched whining sound that happens only when the car is moving under acceleration. If I just rev the engine when it's parked no noise.

 

The only thing that makes a noise like that on my truck is the fan but it goes away when the engine is warmed up but not too hot. Does the noise every go away? Does it change frequency with the engine RPM?

Frank

 

Yes it changes frequency with the engine RPM but if I rev the engine when it's in park no noise. It's definitely not the fan noise you are talking about.

 

I have exactly the same problem. When its cold and you start driving it starts at about 2200 RPM and if you step on the gas it vanishes. And I can hear it ones in a wile when engine is warm.

P.S. Just fishing for ideas. as it was specified before..

 

It could be your speedometer cable that makes noise because it is speed related. The noise can start at different speeds, sometimes depending on the outside temperature.

 

When i bought my truck the guy said he had the speedometer cable replaced, and that it whined on cold days. So now that is starting to cool off i've noticed this problem.

He said the cable was over tensioned and binds in the casing somewhere making the noise. So thats what it is but i haven't found any way to fix it yet, or the time. If someone has done it before or has a good manual for this part, would be a good help. Chur.