CLS 55 no boost/power loss
The "Low battery, convenience functions unavailable" could be either your battery or your alternator. Both also known issues. If you're around 100k on the original alternator my bet is that the alternator has or is on its way out. I just had mine replaced a few weeks ago due to the same message.
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What belt is the supercharger using if they didnt change ir along with pulley it wont be long enough and slip.
Torque app has a setting for showing the vaccum in psi or in hg or whatever so you need to change that in the settings. Also if your seeing like 20psi boost you need to tell it to adjust for atmospheric pressure which is like 14.7 psi at sea level or something..
Post up the boost your seeing at WOT and your IATs after 2 back 2 back wot pulls.
I think you may need a new belt and some cooling upgrades sounds like the tune made the car faster so you must be seeing boost??? With that 77mm and no cooling upgrades you probably heatsoak quickly
If you have no boost at all I think your clutch magnet may not be workin properly.. I haven't any experience with this but I have seen people's fail on the forum before.
An easy solve if that is the case would be a fixed pulley I guess or just get electricity back into the clutch.
I havent got the tune uploaded from Tony yet Im just waiting on him to get back to me with the file. The IATs have been great since I changed the IC pump, stay within 15-25F of ambient. It looks like a factory mercedes amg belt as I read the writing on it. I should be changing out that belt I presume for a Gates belt but I dont know what size to get. More confused now than I was when I first got this car
I know you can use a boost and vacuum setting and another manifold pressure sensor or something from the list of active sensors try a few of the different ones that look relevant and see if you can find something that shows boost...Might be hard if your not making any I guess. In my experience (limited) the in/hg has always been a vaccum value and boost has been in PSI but I've mainly used PSI both negative and positive so can't be sure.
Belt size I think should work (hard for me to say coz I have a belt wrap kit) Gates K080505HD or similiar. The tensioner should make it so it doesn't matter too too much if its a bit long, but that belt is 5mm shorter than factory so should help IF slipping is your problem, but it'd have to be slipping completely to not generate ANY boost.
Why don't you try taking off your supercharger pulley belt and run the car, see if it runs basically the same to confirm the supercharger is not engaging despite being driven by the belt. If its running the same must be either a bad clutch magnet or BPV is stuck open maybe?
Whats he quoting for labor? I couldn't imagine it should take too long!






