please help!slk with lack of power

[apollo]

Hi there,
Please could anyone help me with a problem i have at the moment with a 97P slk 230 kompressor auto?
I just picked the car up and to be honest I thought the car was running fine.
Ticking over nicely, pulling away fine also driving sensibly.
But then I had to pull out into a gap of traffic so pushed the pedal to the floor when I discovered there was no power in it at all.It just seems as though its holding back and spluttering.
I took it to my friends garage and he put a diagnostic on it and it showed that no.1 and no.4 plugs had malfunctioned at some period.
As it has 2 coils, one running 1 and 4 and the other running 2 and 3, I jumped to the conclusion that it may be one of the coils breaking down under load, so i bought a new one.This didnt make any difference.
Could anyone please give me any ideas?
To recap, this car drives really well, and idles well, but put your foot down hard and its not going any where.
Im edging towards the throttle body and the ecu but really not sure what to buy.
Has anyone unfortunately had the same problem to give me a little advice?
many thanks
sorry , not sure whether it should be in this section or the other
ken

 

[Uncle Benz]

MAF sensor should be your first port of call. Plenty of info here about it...

 

[apollo]

Thankyou, but this car i dont think has one unless its combined in the throttle body as its got a siemans vdo system on it.
I ll try and post a photo
cheers
ken

 

[bibamus]

Has it been serviced recently? I would change the plugs and fuel filter, then look at the plug leads.
Allan

 

[apollo]

Thanks Allan,yes all that been checked. As someone kindly just suggested going to try and look for the MAF in the morning.
thanks again

 

[Ultymate]

The photo you've posted above is not the throttle valve, It's the bypass valve that dumps the Supercharger pressure back into the aircleaner at idle.Your MAF is in the inlet duct on the opposite side of the engine down behind and towards the bottom of your radiator;-)

 

[apollo]

WoW!!!!
I really would like to thank everyone for their time and effort on this.
I took the car to my local garage a couple of weeks ago and they told me it didnt have a maf sensor and pointed towards the throttle body itself on the left.They said it must BE BUILT IN TO THAT SO UNFORTUNATELY IVE BEEN ASKING EVERYONE FOR THE WRONG THING.
On your advice, i looked this morning and there it was. I took it off and cleaned it ,put it back but still run rough.
Went and bought a new one, fitted it and hey presto its fantastic!
Problem solved.
THANKS AGAIN EVERYONE FOR YOUR HELP.
cheers
ken

 

[television]

WoW!!!!
I really would like to thank everyone for their time and effort on this.
I took the car to my local garage a couple of weeks ago and they told me it didnt have a maf sensor and pointed towards the throttle body itself on the left.They said it must BE BUILT IN TO THAT SO UNFORTUNATELY IVE BEEN ASKING EVERYONE FOR THE WRONG THING.
On your advice, i looked this morning and there it was. I took it off and cleaned it ,put it back but still run rough.
Went and bought a new one, fitted it and hey presto its fantastic!
Problem solved.
THANKS AGAIN EVERYONE FOR YOUR HELP.
cheers
ken

How sad that the garage man said built into the throtle body, whats it comming to, enjoy your car Ken.


Malcolm

 

[apollo]

Yeah i know, i took it back and showed him what you kindly told me and he apologised.It was just an error, but it completely threw me off track.
PS. ive got the same as you a 500 sl, no probs with that thank goodness.Thanks again
ken