W202 c 200 Loss of Power

[Jonathan1969]

Hi

Very new to this and i hope someone can help me?

I have a c200 1999 with only 53k genuine mileage. on a recent trip on the motorway i kept losing power at about 60 mph. RAC man thinks it may be the cat on the exhaust. once i turned it off it would accelerate to about 60mph OK but then cut out

At some points it did reach 80mph or so but then cut out again. Even at idle it had trouble getting to about 3500rpm.

I find it hard to believe that the cat has gone. It has full MB service history to 48K and I recently replaced air filter and oil filter.

Thanks in advance
Jonathan

 

[Jonathan1969]

Hi can anyone help?

 

[Andy - TFA]

Hi can anyone help?

Jonathan - serial data first. Get any fault codes read. Absolutely the first step.

 

[grober]

There are 2 things causing a car to cut out-- 1 lack of ignition 2 lack of fuel. First thing to try is replacing the crank position sensor. When was the fuel filter replaced last? Could be a blocked cat but that usually means low power than total engine cut out.
When the engine cuts out what indication do you get on the dashboard warning lights/

 

[JasM]

Sounds like a faulty MAF to me.

 

[grober]

Sounds like a faulty MAF to me.

Good suggestion but not sure if it would explain the cutting out? MAF could be tested by temporary disconnection?

 

[sam-orr]

I have a 98' C200 W202 and experienced exactly the same problem a month or so ago.
AA came out and took several stabs in the dark and gave me bugger all like you and the RAC.

I was told that the coil pack, if knackered will heat up and cause considerable loss of power and juddering (firing on three cylinders) I changed mine AND THE CONNECTORS UDERNEATH, FROM MERC AT £23 for both) replaced the plugs and two leads and BINGO!!!

Problem solved, total cost £160 for two packs from CES, 4 leads (couldn't get 2!) set of Bosch super plugs and the connectors from mercedes parts dealership.

I advise you try this before anything, it's an hours work and the right side of £200.

I then completed the mission to Wisbech and back to Chester in one day and £60 worth of juice.

Most successful mechanical and satisfying experience with a great car I have ever had.

Hope this helps you as it did me.

 

[Jonathan1969]

Sorry i haven't been able to log on for a while. Thank you for your answers. i replaced oil filter air filter(all genuine) prior to this fault. Changed ignition coil and spark plugs on advice of a mechanic who diagnosed a cylinder misfiring. This has helped a bit but the cat still cuts out out and I and cannot overtake at times as the poswer just goes and slow down.

It's also a nightmare when starting if i pull off the there is no power all all it just limps along for a while and sometimes it works fine.

I'm at a complete loss

The car has only done 54k miles and full MB history to 48K

Things do point to the MAF???

 

[Jonathan1969]

Andy - swhat is serial data?

I have no warning lights on the dashboard whatsoever

 

[Dieselman]

Things do point to the MAF???

Yes.

 

[martyz]

^+1 for sure.

 

[Stratman]

You can sometimes get an indication the MAF is faulty by unplugging it. Remove the connector and take it for a drive. Without the MAF the ECU will default to its basic engine map. If there is an improvement in the way the car drives it's a good bet the MAF is faulty.

 

[Dieselman]

To check the MAS connect a DC voltmeter between Pin-5 and Gnd. Expect ~2v at idle rising to ~4.8v at full revs.

 

[Jonathan1969]

Guys thanks for the advice on the MAF. Will try it out before i purchase a new one.

 

[Jonathan1969]

Help again please.

I have replaced MAF and still no change, So far i have replaced the spark plugs, ignition coils, and MAF and i still get the issues, When i start up - if i rev it then it doesn't go far up the revs and feels like it misfires. IOt feels ok after it has been warmed up, It lose power above 60 MPH if i try to accelerate and only then only starts pick up speed if i lift off the accelerator a little. Sometimes it will go above 60 mph but i have no confidence as the power will eventually start to drop.

Any other suggestion or can anyone recommend a Merc specialist in south London (SE1)?

thanks
Jonathan

 

[-speedie-]

Hi!

New to the forums today!

I had accelerating problems in my c200, w202 and it is reading the lambda sensor!!

 

[-speedie-]

Also, sorry for missing this, it has the exact same symptoms...will cause a loss I power due to the lambda sensor not being able to send the correct data...also, you need a fault code reading...mine flashed up a leak in vacuum pressure!

Hope it helps!

-speedie-

 

[rascalmaster]

need to get it plugged in and diagnosed... find a good indie

 

[Mr B.]

If you think the car will make it there is a place in loddon just outside of Norwich that's just does Mercedes they should be able to help you out pm me and I'll give you there number

 

[Jonathan1969]

Thanks for your advice. I get no warning lights whatsoever. i put it on a diagnostic but it suggested changing the spark plugs ( which i did). and the mechanic said that as a result it can show other faults .

Short of changing every part i'm at a total loss. Have no faith in getting to Norwich. has put serious dent in my love of Mercedes.