SLK230k down on power

[wilbur]

Hi all, I have recently bought a 1998 SLK230 auto, and it seems to be down in power. It is slow to pull away and has developed a shudder when driving. I'm not sure the kompressor is kicking in either, it takes a while to gt up to speed and doesnt really go fast at all. I can hear some kind of sucking noise when accelerating but not sure exactly where its coming from. No warning lights are on. All help will be appreciated!

 

[wemorgan]

supercharger owners will know plenty more than me, but here's my guess:

air leak in the inlet system
MAF sensor (I presume these engines have one)
spark plugs & HT leads

failing some simple checks yourself I'd advise a visit to your local independent who has a STAR machine. All the best.

 

[vijilants]

When you have the bonnet raised, and rev the engine you should hear the supercharger click as it kicks in.

MAF can also cause loss of power.

 

[BlackC55]

Air mass sensor would be my first port of call.

 

[flango]

similar to my clk 230 problem and car is similar year mine was down to air leak in the inlet system as posted earlier, local Indie fixed it incredibily cheaply, get the fault codes read that should point you in the right direction

 

[Dryce]

No warning lights are on. All help will be appreciated!

Our SLK230 had a contaminated MAF.

The engine check light didn't come on initially - on one long journey we had a slight shudder every so often when cruising at speed which I initially thought was a misfire and the car felt a bit down on power. The light came on a couple of weeks later.

 

[wilbur]

Thanks for the input, I replaced the air filter and spark plugs today, also put a fuel additive through it. Initially the car seemed a lot better, then while driving tonight the problem happened again! It dooe seem like a misfire, but if i switch the engine off and back on the problem goes away for a while! Silly question, but can anyone point me in the direction of the MAF? Thanks again!

 

[wilbur]

Just remembered my dad has the same car as me so I will pinch his MAF to try on my car and see if that sorts it! :bannana:

 

[wemorgan]

but can anyone point me in the direction of the MAF? Thanks again!

It's attached to the plastic air inlet pipe just after the air filter.

 

[sweeper]

It's attached to the plastic air inlet pipe just after the air filter.

In fact it is attached to the pipe coming out of the intercooler, on the left hand side of the engine (right hand if viewed from the front) this comes up and is attached to the inlet manifold (throttle body) with a large cast elbow.

 

[wilbur]

Nice one, I'm gonna steal the one from my dads car at the weekend and see how that goes!

 

[vijilants]

Nice one, I'm gonna steal the one from my dads car at the weekend and see how that goes!

Beware of simply swapping the MAF without resetting the ECU or you may find that the problem appears to be still present.

I'd say get the codes read from the ECU first and see if it shows up anything. Also try disconnecting the lead from the MAF and see if there is any difference.

 

[wilbur]

Many thanks for all the help guys, I replaced the MAF sensor at the weekend and the car runs and drives much better now, much smoother through gear changes and whats more I have plenty power again! So thanks all for pointing me in the right direction! :bannana: