marw

Last weekend i experienced some really weird symptoms with my car. It has been keept in outside storage for 3 months during winter. Started fine and was driving around, when i floored it the ESP light came on and no response from accelerator pedale anymore. Car just lost all power.. Had to restart, car ran fine. Floored it again same thing, with a yellow engine diagnostics warning light lit up on dash. Restarted car ran fine, engine light was still on. After 1 hour standing still the yellow engine light dissapeard. Drove the car for 15 minutes did not experience any problems, but never had the guts to floor it again, was worried of getting stranded on the highway.

Should i be concernd? Was reading about bad throttle bodies causing these problem. Or could this be an easy problem like a weak battery? Before i put the car in storage i changed wheels. Car also had a Supercharger intercooler replaced 2 months before storage. New Gearbox, radiator, etc.. Car is costing a fortune and seems to be breaking down all the time even with a perfect service history behind it..

mrobinso

The car is definitely going into "HOME" mode as it is referred to in the owner's manual, or "limp" mode as it is more commonly known. Review your manual for more information about this "mode". I cannot answer as to what may be causing this to happen in your vehicle, hopefully someone else may have an idea.

Dingleberry

did you let the car warm up before trying to floor it?

the car will go into limp mode if you floor it when the coolant temp is below a certain threshold

marw

Yupp i waited a while before flooring it. Coolant temp was normal, around 190F.

Never had this problem before either. Going to try the car this weekend again. It scares the **** out of me when the throttle pedal stops working. Extremly annoying when you have traffic behind you aswell.

Newzchspy

IC PUMP, Get a Johnson

Q: Does it only do this ONCE the car is warmed up??? If so, IC pump. Very well known problem with C32.

marw

Dont think so mate. The IC pump was changed a year ago. Car is driving fine, except when flooring it and when ESP kicks in. I think its ESP related or throttle body not sure. Guess i need to check error codes.

ddtham

Had this problem once last year, ESP light kicked in when driving somewhat aggressively. I cleaned the electrical connectors on top of the supercharger and it never happens anymore for more than 8K miles.

Good luck!

Newzchspy

I replaced my Throttle Body last year and had the same problem, except that my ESP light didn't go on???

Newzchspy

Got a code for us???

marw

Dont have a scanner myself so guess i need to book an apointment with the stealer. Is it possible to buy this instrument yourself, in that case which one do you recommend?

marw

Thanks. Will try this. Do you mean the connector in the back portion of the supercharger, close to where the intake pipes meet? I think its the throttle body that sits there, but not sure.

evilsaint

^ This. When I first got my 32, I had this SAME problem after I may or may not have been hooning around a bit (in Mexico, of course >_>). Dealership replaced a couple of the engine wiring harnesses and I haven't seen the problem in 3+ years :: knocks on wood ::

Just start unhooking them one by and cleaning the contacts. My SC pump was actually dying at the same time, but the symptoms were totally different once it fully kicked the bucket a week after I got the car back.

marw

Hooked up a OBD2 reader: Launch Creader V.

One code was stored. P0123.

Throttle/Pedal position Sensor/Switch A- Circuit High Input.

I first tried clearing it, did not work.

So i did the throttle reset procedure with ignition on in second position. the gas pedal to the floor for 30 sec then ignition off, fot off, wait 2 min.

After doing that i was able to clear the code. I did not drive the car since its ice outside in this area. I guess ill have to wait for warmer weather.

I think the code will most likely come back when i will start driving again, but my question is if i need a new pedal asembly or a new throttle body? Any ideas?

Gramma_Benz

I got this code before too, for some people, they have been lucky and just replaced the pedal position sensor. For me, my mechanic had a code reader that read some hidden codes that my code reader wouldn't.

Turned out I needed my throttle body rebuilt as I was having the same problem as you.

Good luck!

marw

Thanks for replying. Gramma_Benz: Did you have the exact same symptoms, Limp mode when flooring it, but driving ok in none aggresive driving?

Br,

Martin

Mark.D

Is this the "Button" behind the pedal that is depressed when floored? I believe this button disengages the A/C compressor, downshifts, etc for max. performance.

Gramma_Benz

Yeah, it was always when trying to floor it. And on the freeway, it just wasn't giving as much gas, so it was much slower.

But, cross your fingers, maybe it is just your pedal sensor. Mine was throwing some other codes pointing to the throttle body too.

Newzchspy

+1, had the same thing happen last fall.^^^

marw

Alright so order a new pedal assembly and try to replace it first i guess. Does it require any special tools or just some screws on the floor? Also the throttle body can that be removed without removing supercharger, hard?

mustang281man

sounds like the pedal is your issue. ive had to replace one in the past that did that had the same symptoms as you. IIRC 2 10mm nuts and the electrical connector to remove it.

Apox

I have the same problem, except it doesn't throw any codes, or light any lamps in the dash. My mechanic can't figure out what's wrong. I might have them replace the IC pump nonetheless, but that would be a waste if it's something else
Update us if you figure out what's going on.

Is rebuilding the throttle body expensive?

doom239

Check for belt slippage!

marw

Updating to people who might experience this themself and looking for solution.

I replaced the Accelerator (Throttle) pedal assembly. Its a 1 10mm nut with washer, there is a black plastic cover on top of it that is easily removed with flat screwdriver. Changed myself outdoors under 10 minutes, and im not a good mechanic.

Anyway. The car runs great now and really eats the rear tires. The shifts seems smoother. When i lift my foot of the throttle the car does not get small jerk like before.

evilsaint

Any chance you can post a part #? Seems like another one of those little cheap "smart AMG owner's preventative maintenance" items to try out, problems or otherwise

C_DirtyTwo

I recently started having this same problem.

I start the car, it has a little bit of a weird idle (a little higher RPM's than usual) and ESP warning comes on in the instrument cluster with no response from the gas pedal. I had a code for B28 which is the MAP I believe, but I do not think that'd cause the problem...

any suggestions? I really hope its not the throttle body.