Odd Kompressor power problem, one for the boffins?

[John Jones Jr]

Here's what I would consider an odd Kompressor fault on my W202 C230K.

It's losing power suddenly at approx 4500RPM, loss of pressure from the compressor, back off and the car drives like an N/A. Stop, switch the ignition off & restart all is perfect until similar high rev's.

Now, I know full well the first port of call is to get the codes checked but between one thing and another I can't get that done for a week or two. I'm also aware there's many threads on lack/loss of power on W202 & W208 Kompressors but from what I've searched none have reported the exact same symptoms/problems etc.

I've checked the boost pipes, the wiring to the compressor air bypass valve, cam sensor & magnet. There's a new MAF fitted, along with plugs (one grade cooler), fuel filter, air filter (K&N) etc. I've also looked at the vacuum pipes, all seem o.k..

The only part I'm not too happy with is the fuel pump, it's a bit noisy (heard worse) and maybe its not giving full pressure. So, a question. If there was lack of fuel pressure (engine running lean) especially at high rev's would the engine management go into fail safe and shut the compressor down ie. open the compressor air bypass valve or disengage the clutch?

Any ideas or experience of such a fault?

Cheers in advance.

 

[flango]

Mine used to do this intermittently and I never really got to the bottom of it but when I had the other problems with the kompressor dropping out I changed the cam sensor and it's never done it since, coincidence I don't know but the problem disappeared.

On early 230k cars the fault codes often point you in the wrong direction and fool you into changing parts that don't need changing, not sure where you are but the 3 Indies on here that know these cars well are

PCS (Olly) Portsmouth area
Mercland (Jay) Nuneaton
TMS (Ian) North West

But looks like you have checked all the problem areas I could suggest

Good luck and hope you cure it

 

[Whitey]

I had intermittant power problems and changed the cam magnet as it was rattling at idle- it still rattled after replacement though !

A new MAF solved my problems - I know you've just changed it, but could you swap in your old one ?

 

[Whitey]

Come to think of it, I changed the cam magnet as it was weeping oil.

 

[John Jones Jr]

F1, the car is in Ireland a the moment and there is a Merc specialist not too far away but they're busy and are down staff due holidays, thus a week or two before they can look at it, more like two weeks. When I get the car back to the U.K. I will be using one of the guys on here but at the moment I'll have to make do.

Funny, you mentioned the cam sensor as I ordered one (Febi) yesterday just on the off chance. Maybe heat from the head is starting to make it malfunction.

 

[John Jones Jr]

A little update. I replaced the cam position sensor but sadly no joy. Still, losing the S/charger at high rev's and again when I switch the engine off & restart all o.k.!

Anyone, got a clue to what might be causing this?

 

[mauno]

pcb in divert gate? worn carbon layer?

 

[John Jones Jr]

pcb in divert gate? worn carbon layer?

Tell more Mauno, please.

 

[mauno]

I had intermittent fault on my c200. disassembled the valve elec. 5 litle copper fingers sliding on it and scraped off the electrocarbon layer causing the trouble. bought some acrylic based electrocarbon paint.fillrd the holes and tadam works fine

 

[John Jones Jr]

Cheers for that, I'll have a look at mine and see what's what.

 

[John Jones Jr]

As I mentioned earlier I changed the cam position sensor this morning and had no joy. So, this evening just on the off chance I disconnected the battery for about an hour. Well, holy be, it's driving like a different car, no loss of boost (it was short run) and there's a different noise from the exhaust and quieter too! Plus, even if I say so myself it seems like quick car.

I'm doing a 300 mile trip tomorrow, fingers crossed the problem is cured even if I don't understand why?.

 

[John Jones Jr]

Trip completed, car pulling like a train! I presume disconnecting the battery set the ECU values to zero and by driving it the ECU picked up new values along with the new cam sensor.

 

[Whitey]

Good to know !

 

[John Jones Jr]

Good to know !

Whitey, if your cam sensor hasn't been changed it might be a wise investment of 35 quid, only a 2 min job too. Worth thinking about.

 

[flango]

Glad you got it sorted