pedal value sensor

[Myros]

just got this error code on the mem's W210 320CDI. Can't get more than 3000rpm out of it in any gear, and kickdown is just window-dressing, more revs ( below 3k anyway) but no more power. I'm right in thinking this thing should still kickdown at about 80 from 5th if we ask it to.

Any ideas as to where this sensor is and how tricky replacement is going to be? I know it's going to be expensive, I've got used to that bit of MB ownership over the years.

 

[Cosworth]

I believe its the elecronic part near the servo where the throttle cable connects to the pedal value sensor.

Whats the part number, I might have one?

 

[Myros]

cheers Cosworth

I'll find out and let you know. Or some helpful soul here will bail me out.

 

[Myros]

the part no

is 0125423317, if any one is interested.

 

[Myros]

so I've replaced the following

throttle transducer- made no difference, still came up against the "wall" of no power.
Charge pressure sensor- made a bit of difference, revved all the way up to the red line in P,
but still sporadic and inneffectual kick-down when driving, and still the "wall" effect.
Air filter, old one not too bad, but new is new. Reset the red indicator thing, to find it had gone red again, and keeps going red after every drive.
MAF, bought a pierburg one from the factors. Made a difference in acceleration, but still eventually the "wall" safe mode kicks in.
I did the throttle reset routine yesterday, but haven't had a chance to drive it anywhere I can give it some beans. The mem won't, just in case it lets her down again.
I'm going to have a go at the brake pedal switch tomorrow, and have a shufti for split pipes and hoses etc.
Any ideas anyone, as this is driving me batty, as well as the mem having a car which is coming up short on the power front.
The only diagnostics to come up now are charge pressure control.
Should I be looking at the EGR?

 

[Autofix]

I know its not too helpful but for the money you have spent you could have had the fault diagnosed.

Even though I dont like guessing in general, your symptoms sound like a stuffed Cat. Easy test, split the exhaust and drive it.

 

[Myros]

the first thing I did

was have it connected up to a diagnostic machine. Then we cleared the old codes, ran it, and the "new" codes were pedal value sensor and charge pressure control. The rest is recent history. I've probably still spent less doing all this myself than running it into MB and have them fix just the cheapest thing, the charge sensor. I'm now narrowing things down and still in the bounds of diy-ing. So as a strategy, it's probably not that bad. After all, MB probably wouldn't be any closer to the truth than I am, and would be replacing things one by one until they get to the root of the problem, and charging me the earth to do it as well.

 

[star]

I know its not too helpful but for the money you have spent you could have had the fault diagnosed.

Even though I dont like guessing in general, your symptoms sound like a stuffed Cat. Easy test, split the exhaust and drive it.

+1, Totally agree, any hissing sounds? def try diconnecting cats.

 

[Myros]

Thanks to all the folks who pitched in

here, and on other power loss threads. Had a good shufti around the engine bay, uncoupled the intake hoses, nothing frightening to see, no huge amounts of gunk or anything, just a little dribble of oil from the crankcase breather hose. Cleaned all the bits anyway, squited contact cleaner into the connector on the crankcase hose, and reassembled everything. Mounted the new brake light switch, and went for a spin. Finally got to a bit of road where I could open the taps, and whoosh, we were gone. Pulled like a rocket , kickdown, tiptronic, plain old squeeze of the gas. Reminded me of why we bought it in the first place. I repeated the test at least half a dozen times, so it seems fixed. The brake switch did it, but all the other bits except the throttle transducer all had noticeable effects without curing the fault.
The MAF would need replacing soon anyway as she's a 77 kmiler, and no harm done in the pressure charge sensor being swapped either.

It just goes to show what a little s*d that brake switch can be.

 

[star]

New one to me, never had a brake light switch hold back a car at 3000 rpm.

 

[Myros]

Star,

I had a good look at all the posts I could find on the matter, and the brake light switch showed up as a culprit in a few of them. Had I had a different head on, or not had the diagnostic evidence to go chasing after transducers and sensors, I might well have started with it and saved myself abit of aggro. At under a tenner a go and about 10 minutes of faffing, it's worth a shot anyway if something wierd is going on with your car.

Here's the one that got me thinking
http://forums.mercedesclub.org.uk/showthread.php?t=13876&highlight=320+cdi+power