My 02 Explorer V8 has a buzzing sound (sounds like a small fan) coming from behind the steering wheel until it is warmed up. It doesn't make the noise at idle, but comes in around when the Automatic shifts into high gear. It is somehow related to RPM in that when I hear it, if I lift off the gas pedal, it stops, but comes back in once I get back into the gas. Once it warms up, it doesn't come back.

I can't tell if it is behind the dash, or on the otherside of the firewall. Everything runs fine, but it bugs the heck out of me. Has anyone else experienced this? Is it possibly vaccuum related or something electrical like a stuck relay? I'm definitely lost. Thanks in advance for any suggestions.

Brent

 

I have an 02 explorer also and it drives me nuts as well. I do not know what is causing it either. I have an XLT which do you have?

 

IT's an XLT as well. I am thinking that is on the other side of the firewall in the engine bay somewhere, because now that it is warmer and my windows are down, I can hear it when passing jersey barriers.

Anyone have any ideas? I don't see much on that side under the hood. Is it possible that the fuel pressure regulator could make this noise? I'm still lost.

 

Rocfris -- Have you found out anything about this? Still the same here. Everything seems to work fine, but it is still driving me nutty.

 

I found the below TSB that sounds similar to this issue I am having. This morning, my Explorer would crank but would not idle (just like my 99 before replacing the IAC). So I have it scheduled for the Ford shop on Wednesday.

While I beleive these are unrelated issues, I would like to see if anyone knows anything about this TSB so I can have Ford check into it on my truck. Any help would be greatly appreciated.

TSB 15489--"SOME VEHICLES EQUIPPED WITH 4.6L ENGINES MAY EXHIBIT A HIGH FREQUENCY WHINE NOISE (HAIR DRYER TYPE NOISE), THAT LASTS FOR 30-60 SECONDS AFTER COLD START. *TT

 

My Explorer buzzes when in high gear sometimes because it shifts too early so the RPMS are too low. If the buzz goes away after the RPMs go above 1500, then that is probably the problem. Lifting off the gas will also make it go away. Once the car is warm, it has more power and the shift points are later. If the RPMs are above 1500 after the shift, this is not your problem.

The buzz at low RPMs is a result of the low engine detotanation frequency.

So this may not be your issue (it certainly doesn't relate to an IAC problem), but I thought I would bring it up.

 

Hey,has anybody gone under and checked the exhaust heat shields? These are welded onto the pipes and mufflers. The heating and cooling cycles cause them to break loose at the ends. If they do,they can vibrate and cause a lot of strange sounds. Inspect the welds very closely for cracks. If they don't sound solid when you tap on them with your finger tips,then they are loose.
The cure is:a "breeze" clamp (hose clamp) around the end that's loose.That does the trick.
Do not try to reweld.
This is a fix approved by "Ford".

 

I can't speak for neitz, but the noise I describe is not a heat sheild. I had a heat shield break and the sound is much more "Tinny" and was the worst at idle. The hose clamp fixed the problem.

The buzz I am talking about is a lower frequency rumble and does not happen at idle, only when the car shifts too early to the next gear and RPMs are low, similar to an early shift with a manual transmission.

I don't know about you all, but it is really hard to describe sounds in writing! I think it would be a cool project to actually record sounds of each problem and have them posted in a troubleshooting guide.

 

Yeah, mine is defintely not the heat shield nor does it sound like the problem you have in regards to the shifting. It seems to be more of a nuisance than anything since it doesn't seem to affect the performance. I had it at the Ford garage the other week because my IAC is acting up and I told them to drive it and let me know what they thought, and they said they couldn't duplicate it. The guy who drove it must have been on a different planet, because it happens all the time. I'm pretty sure mine is coming from the left side of the engine bay, but the only thing over there are the relays and what I am guessing is the fuel pressure regulator. When I hear it, as soon as I lift off the gas just slightly, it stops. I'm going to test the fuel pressure this weekend, even though I doubt it will help because performance is fine. On that note, if it is the FPR on that side of the engine, how exactly does it work? Is there anything that would cause it to buzz?