Sudden loss of forward motion under acceleration

[LemmyCaution]

FYI I've posted this on PPBB and have had some responses.

1- Yesterday, accelerating at approximately 75% from a stop in first gear, there was a moderate pop from the rear and the car began to lose speed. It felt like an old Alfa I had that used to pop out of first when I didn't fully engage the shifter in the gate. There were no other sounds and no 'burned clutch' smells Fortunately, I was almost at my client office so was able to coast/ push car into lot.

2- Engine revs freely - no issues

3- Shifter feels normal

4- Clutch pedal feels normal, there are no strange sounds when using the pedal with engine running or not running.

5- Can push car back and forth when gear appears engaged (tried 1st, 2nd and reverse) there are no unexpected sounds. It is quiet.

6- CV joints appear to be intact - and besides, there's no noise.

7- Cannot verify whether clutch is engaged or not. Can shift into all five gears - engine running or not, clutch 'engaged' or not.

So - has this happened to anyone else here? I'm thinking clutch failure of some sort or input shaft. Any thoughts about what it might be?

Also - need independent service recommendations (West L.A. - car is in Beverly Hills, I live in Playa Del Rey) as I don't think I'm to tackle this myself. I spoke to Marcel at Swiss Motors - any feedback on them? I've heard good things about Dutch Treat too. I have an on-going relationship with Pacific Porsche but, given that it may be the clutch, I may be interested in non-dealer recommended mods.

Thanks in advance

Edited January 26, 2007 by LemmyCaution

[CJ_Boxster]

I would go with dutch treat in gardena, they are less expensive and just as good as the dealer is.

[Jinster]

FYI I've posted this on PPBB and have had some responses.

1- Yesterday, accelerating at approximately 75% from a stop in first gear, there was a moderate pop from the rear and the car began to lose speed. It felt like an old Alfa I had that used to pop out of first when I didn't fully engage the shifter in the gate. There were no other sounds and no 'burned clutch' smells Fortunately, I was almost at my client office so was able to coast/ push car into lot.

2- Engine revs freely - no issues

3- Shifter feels normal

4- Clutch pedal feels normal, there are no strange sounds when using the pedal with engine running or not running.

5- Can push car back and forth when gear appears engaged (tried 1st, 2nd and reverse) there are no unexpected sounds. It is quiet.

6- CV joints appear to be intact - and besides, there's no noise.

7- Cannot verify whether clutch is engaged or not. Can shift into all five gears - engine running or not, clutch 'engaged' or not.

So - has this happened to anyone else here? I'm thinking clutch failure of some sort or input shaft. Any thoughts about what it might be?

Also - need independent service recommendations (West L.A. - car is in Beverly Hills, I live in Playa Del Rey) as I don't think I'm to tackle this myself. I spoke to Marcel at Swiss Motors - any feedback on them? I've heard good things about Dutch Treat too. I have an on-going relationship with Pacific Porsche but, given that it may be the clutch, I may be interested in non-dealer recommended mods.

Thanks in advance

Sounds like MAF. When my MAF failed, twice, the car wouldn't accelerate properly. It gave no CEL light either.

[Glyn]

If you can select gears with the engine running without depresing the clutch then you have a drive failure, there are a few causes for this

1 Clutch has broken up - the clutch plate splined centre has broken from the outer friction plate

2 The splines on the gearbox spigot shaft (the input shaft which engages with the clutch plate splines) have sheared

3 Differential - a drive shaft has broken.

The most likely is the clutch plate breaking up.

Glyn

[LemmyCaution]

If you can select gears with the engine running without depresing the clutch then you have a drive failure, there are a few causes for this

1 Clutch has broken up - the clutch plate splined centre has broken from the outer friction plate

2 The splines on the gearbox spigot shaft (the input shaft which engages with the clutch plate splines) have sheared

3 Differential - a drive shaft has broken.

The most likely is the clutch plate breaking up.

Glyn

[LemmyCaution]

If you can select gears with the engine running without depresing the clutch then you have a drive failure, there are a few causes for this

1 Clutch has broken up - the clutch plate splined centre has broken from the outer friction plate

2 The splines on the gearbox spigot shaft (the input shaft which engages with the clutch plate splines) have sheared

3 Differential - a drive shaft has broken.

The most likely is the clutch plate breaking up.

Glyn

Thanks Glyn - Hopefully one of my independent resources schedules will open up in the first few days of the new week. I would take it to my dealer but they will not install an aftermarket clutch kit/lightweight flywheel if in fact it is the clutch. I hope it is not the gearbox/transaxle.

The clutch splined center attachment to the friction plate doesn't look all that robust on these clutches.

[LemmyCaution]

FYI I've posted this on PPBB and have had some responses.

...

Sounds like MAF. When my MAF failed, twice, the car wouldn't accelerate properly. It gave no CEL light either.

The MAF? Either you didn't understand my post (the subject line is not very descriptive - my apologies) or you have a great sense of humor!

The engine runs great. No problems there - it is a mechanical problem somewhere between the business end of the crankshaft and the wheels. Gearbox/clutch etc.

[Jinster]

FYI I've posted this on PPBB and have had some responses.

...

Sounds like MAF. When my MAF failed, twice, the car wouldn't accelerate properly. It gave no CEL light either.

The MAF? Either you didn't understand my post (the subject line is not very descriptive - my apologies) or you have a great sense of humor!

The engine runs great. No problems there - it is a mechanical problem somewhere between the business end of the crankshaft and the wheels. Gearbox/clutch etc.

Dam I wish I can claim this one on humour. :) But, just re-read your thread. Are you saying that you car won't move at all? I must have misinterpreted as it having poor acceleration. Apologies. And good luck.

Edited January 28, 2007 by Jinster

[wvicary]

Had a similar problem on an Audi..... turned out to be a CV joint. The joint failed but didn't damage the rubber boot so everything looked ok at first.

[Glyn]

Lemmy, the weak link in the chain is the clutch plate, they are robust but not as bullet proof as the gearbox or transaxle, i would be very very surprised if anything but the clutch is at fault.

My original trade was a motor mechanic and i have continued to keep my hand in over the years after leaving the trade.

The Boxster is a bit of a lemon for silly niggly faults but all the major parts are pretty solid, guess you will worry until you get the final diagnosis.

If spigot shaft broke or transaxle or even a CV joint it would have made a very very loud cracking noise - which you have not mentioned.

Let us all know how you get on

Glyn

[wvicary]

That was the odd thing when the CV joint broke..... it was as quiet as a grave, even when we put it in first gear and let the clutch out. With the broken metal bits in there I couldn't believe it didn't make a sound. We could see the axle shaft turning in the joint and it did start to vibrate/rumble when we reved it up. Whatever it turns out to be I hope it's an easy fix.

[Glyn]

That was the odd thing when the CV joint broke..... it was as quiet as a grave, even when we put it in first gear and let the clutch out. With the broken metal bits in there I couldn't believe it didn't make a sound. We could see the axle shaft turning in the joint and it did start to vibrate/rumble when we reved it up. Whatever it turns out to be I hope it's an easy fix.

But with your problem you would have had the speedo reading working as you reved whilst in gear as the CV is at the end of the driveline - but most unusual not to have made one hell of a bang when it failed.

Glyn

[wvicary]

Sorry Glyn I can't remember if the speedo was reading or not anymore. We couldn't believe it didn't make a noise as well....... only kinda rumbled when you rev'd the hell out of it.

[LemmyCaution]

Sorry Glyn I can't remember if the speedo was reading or not anymore. We couldn't believe it didn't make a noise as well....... only kinda rumbled when you rev'd the hell out of it.

Thanks for all of the support - sorry I couldn't respond sooner but, I've been swamped with work. This morning, I had the the car pulled out of the parking garage, placed in the end parking spot on the street where it was then put on a flatbed to go to Dutch Treat (thanks for the affirmation CJ).

People complain about Boxsters being too common in L.A. - the upside to this is that both of the drivers immediately said "Oh Good you have the towing eye". The flatbed driver had just the right size planks and already had four cloth straps ready for the wheels so no need to fuss over loading the car.

Robert from Dutch Treat just informed me that it is a broken axle joint - Not sure if it is on the shaft side or not - and that normally results in a clunking noise. CV joint boot remained intact masking the problem further.

Thanks again - I'm driving a rented Murano which IMHO is ugly as sin but is really fun to drive especially in the rain with AWD except that it reminds me never to buy a car with non-HID lamps.

Edited January 31, 2007 by LemmyCaution

[CJ_Boxster]

Im glad you fixed it!

[wvicary]

Glad it isn't anything too serious.... you'll back on the road in no time.

[986Jim]

Broke an axel huh.. I had that same noise on my talon but it was the rear diff exploding on me at the track. I have the center diff welded so the car went into FWD mode with 500+whp and all the sudden the car buckes then the front tires light up like a christmas tree down the track hhahah. It was pretty cool. Cost me another diff I had sitting around, no big deal...

The diff was the first thing I thought about, funny the axel broke instead...

[LemmyCaution]

Broke an axel huh.. I had that same noise on my talon but it was the rear diff exploding on me at the track. I have the center diff welded so the car went into FWD mode with 500+whp and all the sudden the car buckes then the front tires light up like a christmas tree down the track hhahah. It was pretty cool. Cost me another diff I had sitting around, no big deal...

The diff was the first thing I thought about, funny the axel broke instead...

Thanks again all for the support and ideas! And CJ, Robert at Dutch Treat is great. He was recommended by another of my local Porsche buddies. I got out for a little over a grand including an oil/filter change. The drive shaft was $663.

To reiterate, he said it's the first he's seen broken like that and that it was apparently fatigued for some time. He noted the discoloration around the break (kind of hard to see but, it's there)