[tom_boy]

I have a CL55, a 2003 with the first year of the blower motor... Back in 2005, I had a new E55.... Loved that car. Was new, then I had it CPO'ed. So, no real $$$ issues to maintain it... Now, with the 2003 CL55 everything is out of pocket... I have had it to the dealer twice, the guy wrenching on it is top notch, even certified on the McLaren SLR, which I believe was the highest HP "55" blower variant.

So, what's the point or the issue????

Well, upon hard (full throttle) acceleration when you lift the throttle fast at high RPM (say 5,000 to 6,500), there is a bucking or surging that I don't recall at all from the E55 I had... I am not a forced air guru, I have had maybe 7 or 8 over the years, but it almost feels like the bypass or blow-off valve is not working on a turbo car. Honestly, I am not sure if a supercharger even has one...

Any thoughts on this one? Clutch is working, belt is tight.

I am open for thoughts/ideas...

Thank you-
Tom

 

[tim687]

Could it be that the tranny is shifting up on that exact moment?

Have you replaced the transmission fluid of the transmission?

 

[tom_boy]

Could it be that the tranny is shifting up on that exact moment?

Have you replaced the transmission fluid of the transmission?

Yes- comprehensive service, including tranny service/flush... It's anywhere above ~5K RPM...with a quick 'lift' on the pedal.

 

[tim687]

It's anywhere above ~5K RPM...with a quick 'lift' on the pedal.

Does it up shift on that exact moment?

 

[tom_boy]

Hi Tim - no... If I lift @ 5K, it stays in the same gear for a few seconds... I need to confirm if it does it in Sport mode only or both... I think both...

 

[tim687]

Hmm, I know that when the rev range is high, the torque converter will lockup to improve the efficiency of the drivetrain. Could it be that causes somekind of a surge? Are there any 722.6 specialists out here?

 

[tom_boy]

Hmm, I know that when the rev range is high, the torque converter will lockup to improve the efficiency of the drivetrain. Could it be that causes somekind of a surge? Are there any 722.6 specialists out here?

So, took it out and thrashed on it last night.... here's what I found out...
1). I need a new IC pump... Bummer...
2). It's noticeable in sport mode.
3). Seems like it either does not do it in comfort mode, or if it does it's hard to notice as there is a quick upshift, whereas in Sport mode, it holds the gear much longer....

Your hunch may be correct... In my mind, it feels like a boost bypass is not working, or the clutch it locked up (it's not)... Also, I though the M113K ran the 722.5, am I wrong about that?

Thank you Tim!

 

[tom_boy]

Found this when searching the www. Car jerks when coming off WOT....? - MBWorld.org Forums