Originally Posted by Fozz

Hi Guys,

I hope someone can help me out here.

This morning I took my N/A for a dyno remap. One the first run it was showing only 192bhp at the flywheel so a loss of 26bhp or 12% from what she should have had new.
I don't expect a 12 year old car with 80k on the clock to still be showing 218bhp but this just seems too big a loss to be normal.
The guy was concerned enough to re-calibrate the dyno - same result and remove the air filters in case they were blocked. Same result. Full diagnostic check showed no errors.
He then spent literally hours trying to remap her. The best he could get was 200bhp an increase of just 8 and 13lbft of extra torque. This is someone who specialises in Mercedes and said that usually SLk320s come in with about 210-212bhp and go out with 20-25 more.
Does anyone have any idea where those 26 horses may have gone and how I might get them back again. With the remap if I can sort the problem I'm now looking at a gain of up to 40bhp if everything is back to how it should be.
I'll check and clean the EGR valve but there's no usual symptoms that there's anything wrong with it.
Blocked CATS?

Any ideas and advice greatly appreciated.

Thanks in advance

Steve