moec32

Hi guys im new here so let me introduce myself the names Mohammed i'm from South Africa. I own a c32 amg and im having some problems with the car which i hope you huys could help me out with.

Car was stock for most of its life and about a year ago i did the 178mm crank pulley,tune,bmc filters and exhaust and thats when the problem started. The conversion was done by a well known tuner in SA.For about 2 months after i got the car back from the tuner the car was fine it ran like a monster and then i started feeling a lack of accelaration.The car was fine the one day and the next a lack of power i would say maybe 15% less.The thing is i took it back to the tuner and they say there is no problem with the car and ive had the obd scanned and there are no codes.there is boost allthe time so it is not the ic pump but it is not boosting as hard as before. i discconected the battery for about 2 hours the once and reconnected it and the power was back but only for a day while driving the car with all its power there was like a surge in power where i only had half throttle in and the car felt as if i had the throttle plated to the floor and the next day the power was down again.Any ideas on what it could be thats causing this would be appriciated.
Thanks

Lenin

Get yourself a data logger and record your IATs. Most likely it is a IC pump.

johnng117

It's either electrical like the harness or the IC Pump. I've had something like this problem.
Does it go into limp mode?

I have spare IC Pump if you need one.

moec32

You guys think it can be the IC pump because the charger does not shut down there is boost but it does not boost as hard as it should.at first i taught maybe its one of the pulleys so i changed all of them with no results.

W203Ramos

.....when you have your foot planted you feel the sc boosting but revs are slow? sounds like TPS. if it's the IC pump the boost would cut out completely until your IAT's go down

ddtham

I would be interested to know what is the cause for this as well.

My car dynoed at 297 RWHP when stock 2 years ago with 78K miles. I had the car dynoed again last week with my current mods (see sig) and got 305 RWHP... lame... current mileage is 115 K miles. I thought the car runs great, but the dyno guy said that there is a slight pinging at around 4000 rpm which makes the AFR jump to 11.8.

These happened at the same dynojet and same operator but it was 105 Fahrenheit last week (it might make a small difference but not 50 WHP) vs. 85 F 2 years ago.

My plan is to replace my old plugs with one heat colder plugs and maybe get a retune from Jerry.

boohooramblers

All sound advice from the guys above.

You may also want to entertain the possibility that you have a boost leak. Did you install phenolic spacers as part of your modifications?
Might be worth purchasing a new set of gaskets under the charge air distributors if you suspect a leak.

moec32

Ok lets see if i can try to describe what the symtoms. power is down i know this because of checking it on a dyno my car gained 35 WKW after the modifications and now its down from that by 25 WKW. the throttle respone is not there like it was also you have to give quite abit of throttle to get the car going before slight throttle input would cause the car to loose traction and she used to start boosting hard from 2500 rpm not anymore you feel a slight kick now at about 3500 rpm. any ideas?

ddtham

We need more info on your mods. Do you have a tune?

I suspect your problem might be related to the wiring harness that connects to Throttle Body. That harness is known to go bad on modded C32s.

moec32

ya the car has a tune but its not a flash to the ecu its via a piggy-back its the unichip q. the conversion was done by a company here in south africa called rgmotorsport.

moec32

Please tell me if im wrong but dont you guys think if it was the TSP or MAP SENSOR it should have thrown a code am i correct?

moec32

Bump Bump
anyone please let me know if the tps or map sensor was bad should it not throw a code?

Lenin

One of the codes for TPS that you should see is P0120. For MAP, you would get codes that reference B28 module. You have to use STAR DAS to pull the codes. You most likely will not get a CEL for these. Have you tried the ECU Reset? Search the forum for the instructions.

Gramma_Benz

Could be your throttle body(TPS), when I was having issues with mine, I was losing tons of power...
throw on a code reader and see if you can pull any hidden codes. Sometimes your car can throw codes without triggering a CEL. That's probably the best place to start your diagnosis.

moec32

Ok thanks guys. ive got your normal run of the mill code reader but it does not give any codes. Will i have to get the codes pulled with the star das?

Gramma_Benz

Not necessarily Star, but a professional mechanic's code reader. Mine won't read hidden codes either, but my mechanics Snap-On one reads everything.

moec32

Ok thanks man i will call the tuner to have the car checked out again then ill let you guys know what happens.

moec32

Hi guys did not have time to take car into the shop but ive booked it in for next week.Ive had time to drive the car and better asses whats going on.Let me try to explain maybe you gus might know what the problem could be. The car seems to have a drag on it like something is holding her back but only once the charger kicks in.You feel a jerk at about 1500 or 2000rpm and that when you can feel the drag on the car.The charger is also making a louder then normal whine.The feeling is sort of like driving a 1300cc car and while driving along you put the ac on and you feel that drop in power.Hope this helps someone to help me figure out whats going on.Thanks

moec32

Oh yes sorry ive done the throttle reset and there is no difference

moec32

haha thanks.Ok i forgot to mention 1 thing about 3 months back i changed the number 4 pulley and the belt and the car was running perfectly for like 600km's then just like that it started with the same problem again but i dont think the pulley could go bad in that little a km's or could it? Could a pulley be causing this?

Zeppelin

So I read all these posts and you say it makes full boost. How do you know?

Even if it is making full boost it might be hot inefficient boost due to a bad or ineffective IC pump.

On some model year C32's the SC will not disengage until the IAT reads like 212F and over. If your IAT's are towards 200F you will not have any power.

moec32

when the car is cold it still feels the same so I assume that the ic pump is fine.

johnng117

Have the car's CODES read and check the IC Pump... 1st thing to do, dont guess.