Hello forum members,

Hope you are all doing well. I recently posted a thread regarding a spare key issue, I can say that has been resolved, I posted this question onto my original thread (link below) and was told it would be a better idea to start a new one so here it is.

https://mbworld.org/forums/clk-class...spare-key.html

Now unfortunately another problem has cropped up. The car in question is a 2005 CLK220 CDI Automatic.

Today while driving along, I experienced what I can describe as "power loss".

What I mean is from a stand still to 30mph (48kmph) the car would sort of run fine, usually the car changes gear around 2500 revs but for some reason it's shifting around 2000 revs, might not sound much, but I noticed that I'm putting more fuel in, in trying to get her to 30 and above 40mph (65kmph) and finally, with much pushing she tops out around 50mph, i use to just lightly put my foot on the pedal but today i found myself flooring it but to no avail , she wanted to stay around 30mph. I also noticed when stopping for lights etc that the "engine braking" is much more noticeable, eg at 30mph when taking my foot off the pedal it slows to 15mph almost instantly.

I didn't think anything off it until I pulled over and turned the ignition off, went to the shops and came back the engine management light came on with the ignition.

I tried revving the engine just with the parking brake applied she would rev no problem up to and beyond 3000

I went to do a preliminary search on the forums and found that it could have went into "limp mode" due to a MAF problem or an array of engine sensory or even a gear problems

So my question is..... what is probably wrong with the car ? Common causes? And what is the worse case scenario (eg worst and most expensive part that has failed) and what is the least pricey-ist problem here.

Thanks again for you help in advance

Oh if you can direct me to previous thread that would also be helpful too

 

Mercedes don't let you rev your car over 3000 when stopped. that's just how they are designed. usually in limp home mode your car wouldn't move beyond second or third gear. and wouldn't revv beyond 3000 nomatter what. that car wouldn't even be drivable, you won't just feel its loosing power. you got to check what turned on your check engine light. a lot of things can cause what your describing.

 

Thanks Daniel, sorry my inexperience is showing there.

I got the car checked out well I got some good news the reason it was loosing power was that the " valves that regulates any unburnt fuel to reenter the engine to be combusted, that valve has become clogged" (i couldn't remember the full name of the valve in question) with "carbons" due to too much city driving and what he calls " not ragging it enough".

He reset the fault code and has told me take it up to the motor way for some high speed driving and rev the engine for a bit to clear the valves. When setting off at lights to floor the pedal and rev the thing before setting of

He also told me to stop putting in "supermarket fuel" and use branded fuels like BP Ultimate. If in the event I do use supermarket fuels I should put some additives in or mix it with some BP fuel.

He also said that the majority of the problem was due to it being a diesel engine the valves get clogged more than petrol engines it's far less common.

Would you guys agree with his assessment ? At the start of the thread I did say that this is my first merc and diesel, it sounds like a funny assessment to me my driving style is far less "aggressive" but more "gentle" in nature

 

No need to apologize for that! Ive learned most of what i know from this forum! I really dont have experiance with diesel engines. But your mechanic's advice sounds solid. At least he didnt try to tell you to open up your engine and change your valves!! But when carbons affects your engine to the point where your check engine light comes on its usually more serious then that. I really wish i had better experiance with diesels to really tell you if thats a sound assessment. You'd be better of getting help posting a thread in the clk forum specifically. Realy sorry we keep telling you to post again hehe but you want the right people to see your post. Forum is full of knowledgeable people.

 

Thanks for the reply, hopefully it should be fine from now till its MOT (touch wood)

Thanks again for the help it's much appreciated