///M3UT
01-16-2006, 10:17 PM
OK, 95 M3....hearing a rattle.
Let me be more specific:
I only hear it when excelerating uphill in gears 3 and above. It sounds like marlbes in a can, its sort of a metallic sound, also maybe like plastic chains rubbing against each other. The sound is almost exactly like the sound the car makes when its about to die if u let the clutch out too fast.
Ive looked into the VANOS problems, but i dont feel that this is the cause, becasue i ONLY hear it when accelerating hard uphill in higher gear (RPM is way above 1500, and i hear it all the way from about 1.5k to 3.5k, so i dont feel that im lugging the engine). When driving and accelerating on a flat surface or downhill the engine sounds fine.
I have had it inspected twice, all filters are new, new serpentine belt and tensioner, and brand new flex disk. No one has mentioned anything about a bad VANOS or timing chain/tensioner.
Here are the conclusions i have come to so far:
1. its not the lifters - only hear it at high RPM
2. Not the oil pump - no oil pressure light (although oil level is min)
3. Not the chain tensioner - no rattle with RPM drop, runs fine at low RPM
4. Not the Vanos - cannot be heard at idle
This is what ive concluded, but if im wrong or misinterpreting something please let me know what it is and why.
Now, i have been running the car for the past week or so on midgrade gas (below the recommended octance level). could this be the cause? Maybe the knock sensors are compensating for most of the knock and leaving me with this rattle when the car is under strain? (long shot yea...)
Like i said before the oil level was very low tonite when i checked it, but the car was doing this before when the oil was right between the two notches.
well, let me know what u guys think, thanks fellas!:help
Let me be more specific:
I only hear it when excelerating uphill in gears 3 and above. It sounds like marlbes in a can, its sort of a metallic sound, also maybe like plastic chains rubbing against each other. The sound is almost exactly like the sound the car makes when its about to die if u let the clutch out too fast.
Ive looked into the VANOS problems, but i dont feel that this is the cause, becasue i ONLY hear it when accelerating hard uphill in higher gear (RPM is way above 1500, and i hear it all the way from about 1.5k to 3.5k, so i dont feel that im lugging the engine). When driving and accelerating on a flat surface or downhill the engine sounds fine.
I have had it inspected twice, all filters are new, new serpentine belt and tensioner, and brand new flex disk. No one has mentioned anything about a bad VANOS or timing chain/tensioner.
Here are the conclusions i have come to so far:
1. its not the lifters - only hear it at high RPM
2. Not the oil pump - no oil pressure light (although oil level is min)
3. Not the chain tensioner - no rattle with RPM drop, runs fine at low RPM
4. Not the Vanos - cannot be heard at idle
This is what ive concluded, but if im wrong or misinterpreting something please let me know what it is and why.
Now, i have been running the car for the past week or so on midgrade gas (below the recommended octance level). could this be the cause? Maybe the knock sensors are compensating for most of the knock and leaving me with this rattle when the car is under strain? (long shot yea...)
Like i said before the oil level was very low tonite when i checked it, but the car was doing this before when the oil was right between the two notches.
well, let me know what u guys think, thanks fellas!:help