SL55/63/65/R230 AMG SL55 What The Heck!?

Nov 28, 2020 | 01:27 AM

Jigginadeal

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2003 SL55

SL55 What The Heck!?

I could use some help guys.
I purchased a smaller s/c pulley, tune and belt wrap kit from VRP Performance. Now when I get on it a bit and let of the accelerator a little the car jerks violently. It feels like something is not disengaging or like something in the drivetrain should disconnect and freewheel but remains locked up. Does this make any sense to anyone? Belt wrap kit causing this or maybe the s/c not disengaging properly? You guys are the gurus. I'd sure appreciate your opinions.
Thanks, Bill

Nov 28, 2020 | 10:58 AM

poppyboy

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From: Lincolnshire, IL

2005 SL55 AMG

Did you do a tune? Any change in the stock pulley requires an accompanying tune. If so, with a feeler gauge, how’s the gap between the pulley and clutch plate? Spacers enable you to keep it within spec.

Last edited by poppyboy; Nov 28, 2020 at 11:02 AM.

Nov 28, 2020 | 11:26 AM

Jigginadeal

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2003 SL55

Yes sir i did a Race IQ tune as well as their smaller supercharger pulley. I've not checked the gap but was looking online last night and haven't found the spec yet. That is the next step I guess, and if that doesn't do it I guess I'll remove the belt wrap kit and put the old belt back on for a minute to see if anything changes.
thank you for your response.

Nov 28, 2020 | 12:31 PM

poppyboy

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From: Lincolnshire, IL

2005 SL55 AMG

The spec is .035-.045, But mine’s a bit smaller than that. I already verified with UPD that it’s fine. If it’s too grabby, it will result in premature wear and possibly the jerking that you’re experiencing. I didn’t use a BWK since I only went to 83mm, which was verified as OK. No slippage that I can tell.

Dec 2, 2020 | 12:21 AM

m5zealot

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From: Maricopa Arizona/San Diego California

1988 BMW M5, 1989 BMW M3, 1979 Mercedes 450 SEL 6.9, 2006 SL55 AMG w/ P30 Performance Pack

Quote:

Originally Posted by Jigginadeal

Hey, I'm having the same problem with my Raceiq and 83mm pulley swap. It's definitely not your belt wrap kit because I have had mine for 3 years and did not get this jerking until I did the pulley swap. The weird thing is the 1st tune was perfect no jerking on the 1 - 2 shift. I decided to add a little pop and burble to the tune just for ****s an giggles and that's when I got the jerking when it shifts from 1st to 2nd gear in sport or manual. I measured the gap and it is over the .045 0 more like .054 so definitely out of spec. No way to correct that unless I mill the bearing. Adding a shim would just make it worse. We are going to put the 1st tune back on and see if the issue goes away. I don't think the extra fuel squirted on the overrun is causing this so I doubt that added "bling" is doing it. BTW, the pop and burble is very subtle and only happens on the overrun in 2nd or 3rd gear after WOT. It was a silly experiment but I wanted the ole girl to sound like my C43 for a day. I'll update this post if I have any news.

Dec 2, 2020 | 11:19 AM

Jigginadeal

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2003 SL55

Thanks Poppyboy and M5.
I checked the s/c gap and I'm at .045 so I don't believe that is the problem, but I definitely have a big problem. I've parked the car until I figure this out. I drove it last night and thought I was going to rip my new black series motor mounts out. I'm afraid it's the Race IQ tune and will have to go to Eurocharged. I'm near Houston so it's not such a big deal but just pisses me off that I burned $500 on a tune that is trying to grenade my engine.
M5 let me know what happens when you swap tunes. Fyi my tune does not include the crackle and pop.
thanks!