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View Full Version : Engine Whine: Can someone help Diagnose?



SephirXV
07-19-2005, 08:56 AM
First, vital stats: 1989 LXi Hatch 5spd, completely stock (so far)

Issue:
I noticed a whining when my engine is within 1300-2000 RPM. First thing I thought was a tranny issue, so I parked and played around with it. It does it and sounds about the same regardless of where I am within the above RPM range, whether I'm moving and the engine is under load (in gear, clutch out), or sitting and under no load (either in gear & clutch in OR neutral & clutch out). I even threw it in neutral once on the highway and gassed it, whined just the same. So to me that says that it's probably not a tranny issue. Maybe it's something to do with the engine side of the clutch?
Anyway, in a hope that it was a belt or something loose, I popped the hood and gassed it at the TB. Thing is, it didn't even sound like it was coming from anywhere in the engine bay at all, more like it was behind & underneath. Now I know that the tranny is under the engine, and the gear section is back toward the firewall, but I would think I would be able to hear it, especially since the clutch is between the two.

Anyways, I'm no expert, that's why I come to the forum. Anybody that could give me any idea of what to check or where to direct my investigation would be appreciated.

Blkblurr
07-19-2005, 10:46 AM
Could be your fuel pump if it's coming from the rear. Does it change pitch with a change in engine rpm?

SephirXV
07-19-2005, 11:08 AM
It changes a very little in pitch, but if it were the fuel pump responding to an increased volume-flow, why would the noise cut out at only 2k RPM? The engine isn't overpowering the whine, and the whine isn't fading into inaudible frequencies, it simply stops being made.

To check into your question, could I simply sit my hear under the car near the pump and have someone raise the RPM to an appropriate rate?

FyreDaug
07-19-2005, 12:11 PM
What about an alternator? I have a wierd issue where it would stop at certain rpms... hows your charging system?

SephirXV
07-19-2005, 01:55 PM
I havn't noticed any charge problems since I noticed the noise (3-4 days), especially considering all we have is an idiot light, but I'll try to pay special attention to it and see if I notice anything.

FyreDaug
07-21-2005, 09:17 AM
It might still charge, but it could be whining because of the bearing. But mine with the alt whine was it wasnt charging either. It actually couldnt keep up to engine draw at night.