C32 AMG - P0108 Code

[Neil Mackay]

Morning Gents,

The car is really starting to grate on me now ! As soon as I put something right, something else goes wrong !! So I've had a trouble code P0108 (Manifold absolute pressure/Baromic pressure high input) Which initiates as a pending code, until it flags up again where it turns into a EML light trouble code.

I'm running the following, SL55 Intakes, 65mm EC Pulley and Dyno map, Needswings Coolant split. The code appears whether I use the dyno map or a slightly revised map Jerry subsequently sent through (not to do with this trouble code) It does not run rough, idle rough, or indeed lack any performance when the EML is lit.

Now for some OBDII data........

MAP Sensor measures between 239kpa and 245kpa on WOT (I assume external conditions have some effect on this) Looking at the spec of he MAP sensor they should go upto around 265kpa limit

Boost is estimated at 19.6psi (Dyno tune) and 20.7psi (later tune from Jerry)

I don't recall having this code prior to having the Charge cooler under the supercharger replaced (I know, I should have done the sensor too!!)

So, Jerry feels its not really a mapping issue, so is it as simple as the MAP sensor needing to be replaced???

Thanks for any advice!

 

[Neil Mackay]

Hmm I wonder whether the coolant split might have something to do with it.....? I'm lost with this car! Really need the expert advice of Olly or Paul on this one!

 

[Neil Mackay]

Update! Jerry from Eurocharged has suggested I change back to the standard C32 intakes to see if the SL55 intake makes it over boost! Hmm £350 well spent lol!

 

[Neil Mackay]

Stock induction back on.....still giving a P0108 code.......is there anyone here who can shed any light?

 

[BlackC55]

Have you changed the sensor?

Have you checked the wiring to it?

I would probably do this first.

 

[SLK32AMG]

Hi,
I am having issues with my SLK32AMG all started with my last road tune by Jerry and fitting the sl55 air intakes, problem i'm getting is I can be driving and when I try to accelerate the engine just shuts down like someone has turned the ignition key off, if I let off accelerator and then try again it will clear after about 3 attempts its so annoying you just don't know where you are with it. also I get the traction light flashing and coming on whilst just cruising at 60 to 70 and it cuts power as though you are spinning the wheels. My only problem is I'm not getting any warning lights showing a problem so will need to get it on a star to see if any fault codes showing none showing on my code reader.

I am considering putting the car totally back to stock had no problems at all until started medling and spending cash on mods.

 

[Neil Mackay]

Have you changed the sensor? Have you checked the wiring to it? I would probably do this first.

Hi Olly,

I've refrained from changing the sensor as according to the OBDII logging it peaks at 245kpa and the sensor should handle 265kpa! As you know the MAP sensor on a C32 isn't too easy to get to! I should have got Jack to check it over when he did the cooler! Maybe I'll have a look in the morning! Jerry is stumped!

 

[Neil Mackay]

Hi, I am having issues with my SLK32AMG all started with my last road tune by Jerry and fitting the sl55 air intakes, problem i'm getting is I can be driving and when I try to accelerate the engine just shuts down like someone has turned the ignition key off, if I let off accelerator and then try again it will clear after about 3 attempts its so annoying you just don't know where you are with it. also I get the traction light flashing and coming on whilst just cruising at 60 to 70 and it cuts power as though you are spinning the wheels. My only problem is I'm not getting any warning lights showing a problem so will need to get it on a star to see if any fault codes showing none showing on my code reader. I am considering putting the car totally back to stock had no problems at all until started medling and spending cash on mods.

Yours sounds like a charge cooler pump gone bad?

 

[SLK32AMG]

Yours sounds like a charge cooler pump gone bad?

Its a Newish pump changed when mods done and as it does this even when cold so don't think its that

 

[Neil Mackay]

That does sound strange! Mine did it a few times when cold but literally a split second then back on! I could have bought a second car this year with what my '32 has cost me, so next time it's a potentially big bill I'm getting shot of it and getting an electric car!

 

[SLK32AMG]

That does sound strange! Mine did it a few times when cold but literally a split second then back on! I could have bought a second car this year with what my '32 has cost me, so next time it's a potentially big bill I'm getting shot of it and getting an electric car!

Yes the power loss is total like as I said the ignition turned off not just no pull like when pump fails and trust me when car is pulling and it gets to 4k accelerating fast and then nothing it ricks your neck as its like wacking brakes on and not skidding it takes you by surprise.

What I have noticed since it has started happening and the sl55 air boxes fitted is the supercharger does whine more than before,

 

[Neil Mackay]

Yes the power loss is total like as I said the ignition turned off not just no pull like when pump fails and trust me when car is pulling and it gets to 4k accelerating fast and then nothing it ricks your neck as its like wacking brakes on and not skidding it takes you by surprise. What I have noticed since it has started happening and the sl55 air boxes fitted is the supercharger does whine more than before,

One thing I have come to understand is these cars are very tempremental

 

[SLK32AMG]

One thing I have come to understand is these cars are very tempremental

Yes I agree, I do not think they like being tampered with mines been plagued with issues since mods started that's why I am hoping I can get it back to stock if needed, I still have my original air boxes and supercharger pulley. think im gonna go that way one step at a time in reverse to what I have had done and see if the issue stops.

 

[Neil Mackay]

Would a boost leak throw this code up? Or even the throttle position on lift off? Seems to occur when I've driven it hard then taken my foot off the power, then back on again....sticky throttle body maybe? Can you tell I'm bored lol

 

[BlackC55]

Have you had a look at the throttle body for any gunk build up?

 

[Neil Mackay]

Have you had a look at the throttle body for any gunk build up?

Not yet but I will do! There was some black build up on the butterfly valve in there

 

[Neil Mackay]

Throttle body cleaned, sensor cables checked and appear ok, I've got a sensor to replace this one in the car but there's no way I could get to it! Found a broken jubilee clip on one of the hoses into the inlet and thought I'd cured it! Gave the car a right thrashing, no code plus it completed all readiness tests which it wouldn't before! Switch the car off, then back on, scanned again and the ****ing code appeared again! I'd currently enjoy setting it on fire!

 

[Paulc32]

Would you not recommend buying a c32 then Neil?

 

[Neil Mackay]

Would you not recommend buying a c32 then Neil?

Hi Paul, welcome to the forum! Let's put it this way, all the things that could go wrong with a C32 has gone wrong with mine! If you get one, get a full run down on its history, get an indi to go over it with star and a fine tooth comb and make sure the charge cooler isn't leaking!!! That's a £1500 repair!

 

[marty359]

Would you not recommend buying a c32 then Neil?

Not my old one with the reg X321 AMG that's for sure if you see it for sale run away.