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It's a beautiful clear, dry, day here in Northern VA, the outside temp. is about 32 degrees, it's Christmas and there's no traffic on the roads. So I decide this would be the perfect time to take my Beast out of the garage for a little exercise. Everything is fine, the car is running GREAT, I'm surfing my Sirius radio channels, the volume is low so I can l listen to the exhaust and life is good. I'm on a nice clear stretch of road so I decide to go through the gears, no power shifting, just nice clean easy shifts, rpms below red line. Well at 120mph in sixth gear I notice the engine seems to be losing power so I back off and slow down. Everything "seems" okay but my beast with 12,850 miles feels "underpowered". I turn around, find another stretch of good road with no other cars and go through the gears again just like before. This time I can't get past 100mph and my beast feels sluggish. I slow down and begin thinking "did I burn out my clutch?" On the way home my beast just doesn't feel the same, the clutch pedal is engaging much higher and my power band isn't the same. More bad clutch symptoms?

Upon arriving home I jump on the Board and do a search on clutch problems. Now keep in mind I've followed a lot of the strings regarding M5 clutch problems for over a year now but of couse clutch problems can't happen to me because I drive my beast in a very sensible, reasonable and adult manner. It appears I am wrong!

Here's my question, am I experiencing a typical clutch failure? My car is still under warranty so I'm not tooooo concerned, should I be?

BK in NVA
 

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Discussion Starter #2
Follow-up -

After I posted I drove my beast again. This time I put it through its paces as the saying goes. No problems, smooth accleration, no hesitation, pushed it to about 110. I figured if it was going to break, why not on Christmas Day!

So, I suspect I have MAF problems or, because my beast sits for 2-3 weeks out of every month I have built-up carbon or other contaminents (did I spell that right?) that were being burned-off during WOT. Or, the gas I'm using (Shell 93) is not a good match for the Sunoco 94 (no longer available) I was using. Because I have the Powerchip 94 Gold ECU does that also make a differnce?

Any suggestions?

I'm also looking for a 99-00 540ia sport with an automatic for a daily driver. Any problems with these cars?

BK in VA
 

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I would think that if it was the clutch you should feel "softness" on a hard 2-3 upshift as perhaps one of the first indicators it is getting weak: i.e. WOT through 2nd gear and then a nice sharp shift into 3rd...one that would elicit a huge bark/wheelspin if it was a 1-2 upshift. If you don't get these types of symptoms of clutch slippage, I doubt the problem up high is related to the clutch (not sure about that however).
 

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OK- it aint so :D

Im with CSBM5- doesnt really sound like clutch slippage, but what? I don't know. I've had the clutch slip once as he described. :( (11,000 miles!)
 

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If the clutch were at fault, the engine RPM would soar but the car wouldn't accelerate. It is also highly unlikely that it would spontaneously begin to slip - usually slipping begins following a shift, but not after the clutch is "hooked up" - unless and until the clutch is so badly burned it is complete toast anyway. I am not sure what your problem is, but it isn't your clutch.
 

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Oh man, I hope it aint so. If the clutch was slipping, when you got home/out of the car, you would have smelled the burn. Also as noted, a hard shift from 1st to 2nd along with massive rpms with little acceleration would spell 'slippage'.

Before buying new MAFS, get some Electro Wash cleaner (search forum and google for sources). Try cleaning them and maybe save some $$$$.

Good Luck, Happy New Year! :cheers:
 

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BK in NVA:

Does not sound like the clutch. As Greg said, A hard shift either from 1st to 2nd or 2nd to third would tell you instantly via the tach (and engine screaming) that the clutch was slipping. This is hard to miss.

MAFs or CPS (Camshaft Position Sensor) sound like the culprit here. I tend towards the CPS's because from what I hear they are intermittent then go. But you did not get a SES light, so.....

Cleaning the MAF's could be helpful. Couldn't hurt.

Again you say you only drive it every few weeks. Hmmm.

If you bring it to the dealership and say "No power at 110MPH" well... Some technician will want to test it at those conditions. And the tech could do more damage to the clutch while shifting than you have done in 12,850 miles.

If the problem returns, I suggest the Peake Research tool, find out the codes if any, and proceed from there. If you are a DIY kind of person, there are all the required instructions on this board to fix almost anything.

As far as the ECU remap, I am pretty sure if you have a 94 octane setup, you should use 94 octane. The remap of the ignition timing is expecting 94 octane. At 93 octane, predetonation occurs and, as we know, engine knock is not a good thing.

Lastly at 32°F, there is plenty of cold air coming into the intake system, so power should not be lost from that.

Let us know if the problem returns.
 

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I had this problem while proving a point to a colleage who didn't believe the M5 was a 400HP beast.

I backed off at 130mph (mostly because of his begging and the dash/door grasping :1: ). Turned Dino around and headed back with some agressive shifting and it seemed to be sluggist up to and around 100mph so I drove moderately the rest of the way. Mileage was 14K.

That was a over a year ago and I haven't had the problem since. Go figure??? Post back your findings.

Cheers,
Kevin
 
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