Poor Acceleration

[webush]

Hello,

2001 Boxster S

60,000 Miles

No CEL, but have had one pop on from time to time related to the O2 sensor on one of the banks

The last couple of days I have noticed a lack of power when accelerating. It is particuliarly noticeable when traveling at the lower range of a gear (slow for that gear) but is noticeable to some extent in all gears. When accelerating, the car will rev up about 1,000-1,500 rpm higher but not deliver any additional power until a second later and then the revs drop down to where they were before and begin increasing as the car accelerates smoothly after the initial 'over-rev'.

Sequence of events:

1. Press gas pedal

2. Revs jump 1-1.5 k

3. Car accelerates and Revs Drop

4. Normal power curve (at least I think) after the initial lag.

I haven't had much time to check much of anything but did look at the air filter to ensure it wasn't clogged by leaves as I park under some trees that have been vigorously preparing for winter.

Any help would be appreciated and if anyone knows of a good auto shop in the Brooklyn area that would be helpful.

Thanks. :thankyou:

[therock88]

Hello,

2001 Boxster S

60,000 Miles

No CEL, but have had one pop on from time to time related to the O2 sensor on one of the banks

The last couple of days I have noticed a lack of power when accelerating. It is particuliarly noticeable when traveling at the lower range of a gear (slow for that gear) but is noticeable to some extent in all gears. When accelerating, the car will rev up about 1,000-1,500 rpm higher but not deliver any additional power until a second later and then the revs drop down to where they were before and begin increasing as the car accelerates smoothly after the initial 'over-rev'.

Sequence of events:

1. Press gas pedal

2. Revs jump 1-1.5 k

3. Car accelerates and Revs Drop

4. Normal power curve (at least I think) after the initial lag.

I haven't had much time to check much of anything but did look at the air filter to ensure it wasn't clogged by leaves as I park under some trees that have been vigorously preparing for winter.

Any help would be appreciated and if anyone knows of a good auto shop in the Brooklyn area that would be helpful.

Thanks. :thankyou:

Hard to tell for sure from your description...But what condition is the clutch in (if manual)? If the clutch is worn, it will rev up as it slips....then as it heats it will grab and seem to lower the rev as it connects better, then would continue to accelerate? If the clutch is new or good...I am at a loss.

At 60K if original clutch...You are about due..

Good luck

DC

Edited December 6, 2010 by therock88

[systech]

Hello,

2001 Boxster S

60,000 Miles

No CEL, but have had one pop on from time to time related to the O2 sensor on one of the banks

The last couple of days I have noticed a lack of power when accelerating. It is particuliarly noticeable when traveling at the lower range of a gear (slow for that gear) but is noticeable to some extent in all gears. When accelerating, the car will rev up about 1,000-1,500 rpm higher but not deliver any additional power until a second later and then the revs drop down to where they were before and begin increasing as the car accelerates smoothly after the initial 'over-rev'.

Sequence of events:

1. Press gas pedal

2. Revs jump 1-1.5 k

3. Car accelerates and Revs Drop

4. Normal power curve (at least I think) after the initial lag.

I haven't had much time to check much of anything but did look at the air filter to ensure it wasn't clogged by leaves as I park under some trees that have been vigorously preparing for winter.

Any help would be appreciated and if anyone knows of a good auto shop in the Brooklyn area that would be helpful.

Thanks. :thankyou:

Classic symptoms of a failing air flow sensor (MAF) in my view. You could try cleaning it and if that doesn't change the situation replace it. You can also do a check of the MAF by disconnecting the cable...if it runs better using the default map in the ECU which is activated when no valid MAF signals are received, you can bet the MAF is stuffed.

[1schoir]

+1 on the worn clutch.

Try driving the car at about 20 or 25 mph, and then put it into 4th or 5th gear at that speed...then, accelerate sharply and see if the engine revs go up without a corresponding increase in speed.

If that's what you get, it's time for a new clutch.

Regards, Maurice.

[jibbles44]

I would def check the MAF by running the car with it disconnected temporarily. That diagnostic worked for me. Perhaps just tapping the gas without being in gear and getting the same results would point towards the MAF as well instead of a mechanical transmission problem.

[webush]

Thanks for all the replies and it would seem that it is down to MAF vs Clutch. I bet you can guess which one I'm pulling for at this point. I'm going to pull the plug on the MAF tomorrow and hopefully that solves the problem; however, based upon Maurice's test (acceleration was terrible) it does appear to be the clutch.