Noise after long trips.
 

I did a search and didn't see anything similar, if this isn't right then please point me in the right direction. Ok, I am going to explain this as best as possible since we all know that over the web diagnosis is difficult.

Conditions: Does NOT happen when driving around town. Does NOT happen even if I have driven around town for an hour and have rodded the car even while driving around town. It has ONLY occured 3 times, all of them recent.

One was after a 50 mile freeway trip to an autox, didn't start doing it until about 4 runs in, while I was idling on the grid. One was after a 50 mile freeway trip, I changed the oil, started it back up after it was 'cool' from waiting for me to get everything done, did it right at start up, didn't do it after I got done with the 50 mile return trip. Most recent trip was a 650 mile trip to Oregon which, when I got there it was loud and sounded like absolute shit. It sounded almost like a belt was loose, but not quite, almost as though something was rubbing and causing the noise. I noticed it at idle, it got sort of muffled when driving, but was still there while I drove for the next 15 or so minutes and then was gone when I started it the next morning. I would think it had to do with something that must be soaking up heat and expanding...but don't have a clue what it could be. I didn't see anywhere where that appeared to be the case....so any help is greatly appreciated.

Thanks!

Does it sound like marbles in a can? If so, search for several threads dealing with that sound.

No, it definately does not sound like marbles in a can. It's more like a mix between one of the rotating parts rubbing and a squeaky belt...?

You say you hear the noise at idle (in neutral?). Does the noise disappear when you depress the clutch pedal? If so, it may be the transmission main shaft that rotates when the clutch is engaged (i.e., pedal out) and does not rotate with the the clutch pedal depressed.

But if he/she is in neutral wouldn't he have that noise in the tranny main shaft regardless of whether the car was just started up, or, had been on a long trip?

(he) Allow me to elaborate with some more observations. When I pull the car out of the garage in the morning, (when cold) I get a sounds that's a chirp as it lugs (since it's idling higher warming up it doesn't really need any throttle to pull out of the garage), sound is gone when it's warm. When I was driving around today it has a noise that sounds like a set of loose lifters would sound on a regular piston engine...but combine with a sound like that of the old 1970's VW beetles...but alot more toned down. All of these sounds I believe to be related, but I am unable to pinpoint it when under the hood. It sounds like they are coming from the top of the motor, down by the exhaust, or in the front close to the alternator. Any help with this would be great.

I also had the A/C on for the wife today and when I parked after getting off the freeway from a 5 minute drive, it would idle at like 750-800ish really rough, then go up to about 1100, then back down, that cycle took about 10-15 seconds as it would pause at both ends of that. It also felt like it had no power when driving away from that parking spot. I got it into the higher rpms (above 4500) to try to see if the A/C was pulling the power, but up there I didn't notice much of a difference. The power issue is something that isn't always there, but it just doesn't want to go anywhere when I hit the accelerator. It does gain in speed, but it feels like I am driving a geo or something. I notice no hiccups in the high rpms, nothing feels out of whack, I have no cutting out or surging.....any ideas guys???

BTW: Go48, these are abnormal noises, not just the whirring that goes away when you depress the clutch or the very common 'marbles in a can'. I also suspect that since it was 92 outside that that may have something to do with me noticing these noises more than on a cooler day believe it or not. I just want to have some idea what it is so I can get this shit fixed. I don't have a mazda deal w/i 100 miles of me, so I need to be somewhat sure before I have any work done.

Try to isolate the origin of the noise. Make a redneck stethoscope out of a piece of garden hose. Place one end of the hose at your ear and touch the other end to various points on the engine/tranny. Careful with the moving parts, though.:)

While I've never seen reports of the noises your describing tied to such a post, there are a number of posts on the "hunting idle" you describe and how to adress same.

it could be a number of things making the noise u described. but i would check your a/c compressor first. since there really isnt a whole lot of moving parts on our engine and a/c compressor clutches do fail allot its my first guess.