engine losing power?

[wasted]

I have found that when manually selecting 2nd gear and staying in it in my SL55, after about 3 minutes the engine is reluctant to pull strongly through the rev range. It does not seem to be overheated and there are no messages or lights but it feels like the engine management has put on some limit.
Any suggestions?

 

[toni_007]

I have found that when manually selecting 2nd gear and staying in it in my SL55, after about 3 minutes the engine is reluctant to pull strongly through the rev range. It does not seem to be overheated and there are no messages or lights but it feels like the engine management has put on some limit.
Any suggestions?

Are you selecting the gear at the right RPM/speed? Because 2nd gear can be too hard on the engine from low speed especially if gear ratio is vast.

 

[Rob CCLASS320]

How many miles?

 

[wasted]

Toni - I'm holding it in second to give me good response from slow corners (along some country lanes I know) but need to slow again before needing 3rd for next corner. For a couple of minutes it pulls strongly, but then falls away.

Rob - 85k miles.

 

[Dieselman]

I have found that when manually selecting 2nd gear and staying in it in my SL55, after about 3 minutes the engine is reluctant to pull strongly through the rev range.

I'm holding it in second

Once the rev counter gets well into the red section it's best to let off for a while...

 

[Dieselman]

Toni - I'm holding it in second to give me good response from slow corners


85k miles.

No wonder it's complaining...

 

[SavMan]

It only happens in 2nd or have you only tried it in 2nd? 3rd will be difficult as you could be driving at obscene speeds, try it in 1st to see if it is replicated. I would however as a precaution get your IC pump checked and ensure you have no air in the IC circuit.

 

[wasted]

No wonder it's complaining...

I had a good day at Mercedes Benz World thrashing their AMG around the track, and I saw that these cars were being used continuously all day every day.
Am I wrong in thinking I could do a track day in mine?

 

[SavMan]

Any car can, it is after all just a road that starts in the same place as it finishes. Going around fast is another matter, you should firstly solve your power problem then ensure the car is in tip top condition. Tyres, Suspension, brakes and fluids check these are all OK and the car is running well engine wise then get a helmet and have some fun.

 

[wasted]

Any car can, it is after all just a road that starts in the same place as it finishes. Going around fast is another matter, you should firstly solve your power problem then ensure the car is in tip top condition. Tyres, Suspension, brakes and fluids check these are all OK and the car is running well engine wise then get a helmet and have some fun.

Wise words - will do.

 

[BigH]

I had a similar problem with my SL55, I noticed it one day when a 320D beamer left me for dust on the motorway

It turned out to be a duff intercooler pump, with a new pump full power was back on tap. Without the pump the air intake temperature gets too high and the engine throttles back to protect itself, that is why if you take it easy for a while the temp drops and power is restored, unfortunatley as soon as you start pushing again the temp goes up quickly and you're back to low power again.