SLK 32 ESP Problem?

[radiovintageman]

My 2001 SLK32 with 28,500 miles has just been in to the main dealers for an A service. Additional work included 2 and 4 year recommendations - spark plugs, filters, brake fluid etc. Front wheel bearings were adjusted, and rear axle oil seals replaced. A faulty oil level sensor is yet to be fitted.

Somewhat staggered by the bills, I took the car for a good blast last weekend. On the motorway at high (alright illegal) speeds the car felt as if the speed limiter had suddenly cut in or that ESP was limiting power. Kickdown had no effect, and engine revs limited at 4000 for a while. The transmission did not seem to know which ratio to select. Slowing down, the car seemed normal, and acceleration from a standstill seemed OK.

No warning lights came on at all, and now the SLK drives normally at town speeds.

The dealers will of course get the car back and look at the fault codes. I suspect an error in their work, but they could, I fear, tell me anything, and charge the earth (£99.35 an hour) for labour and parts.

Please can anybody suggest where this fault might lie, so I am prepared to counter my dealer's inevitable bullsh*t?

 

[jberks]

Most likely to be a MAS glitch I'd suspect. Not their fault but it could be that they disturbed some muck from the air filter which then sneaked through and caused a false reading.
As for the £100 per hour - remember you have to pay for all the nice surroundings and admin staff, plus the overpriced kit. The mechanic gets a very small fraction.
It's always worth having a good local indie, if just for the non service work.

 

[radiovintageman]

Thanks, now I've had time to explore the forum I see many similar stories involving MAS/MAF failure. Problems at high speed - high air flow - seem to fit, so I'll research an independent for a quote.

Your comment on dealer labour price is fair enough, naturally the mechanic doesn't see much of the money. The difficulty I have is with being given stories of extra work that "needs" doing priced on an item-by-item basis, with no account taken of the reduced time resulting when dismantling has already taken place for agreed work, e.g. filters and sparkplugs each being costed as individual jobs and added to the full cost of the service.

One member was charged £527 for a new MAS, other members say it's a 5 minute job. Shall I hazard a guess at which end of the range my dealer's quote will fall?

 

[television]

Welcome to the forum, why not change it yourself

 

[radiovintageman]

Hi Malcolm, I would if I could find it! It's not obvious, and if this engine's like the C32 perhaps there isn't one? Anyway,the local independent specialist says he will have a look at the car, and changing the MAS is a quick job.

To update, today the car's performance started off OK, but a few bursts of hard acceleration brought the fault on again. It seems to get fed up with being asked for lots of power, and refuses to play, limiting revs and not responding to kickdown. I hope it has got a MAS and that it is the problem. From forum posts I've read there seem many expensive and difficult to diagnose possibilities! Just worked out that running costs, repairs, tyres, depreciation come to £2 a mile.

I'll let you know if we find out what it is, then I'll sell the b****y thing.

 

[television]

Its 119 in the link if your is a 170046 car

http://www.detali.ru/cat/oem_mb2.as...660716.667&CT=M&cat=19Y&SID=14&SGR=030&SGN=01

 

[radiovintageman]

Thanks Malcolm, but sorry, I can't recognise the intake arrangements from these drawings. My car has an intake tube on each side, 2 air filters, and the intake air ducts are siamesed at the rear of the supercharger. There is no MAS assembly between the filters and the air ducts on either side of the grille.

The VIN is WDB1704662F254448, does that help at all?

 

[BlackC55]

As the intake pipes meet at the back is where the air mass is situated i think. I have not seen a 32 engine for ages so this is just from memory.

 

[Uncle Benz]

As I think you suspect, there is no MAF sensor on your engine. The supercharged V6 does not have one. I would suspect you have a problem with your intercooler pump. I am back in the UK from Sunday and will provide more details then if you like.

Don't panic, the main problem is that the cars are so rare, one dealer does not see enough of them to know what the common faults are. Owners forums are the best way to share experience with the rarer cars. This is a simple problem with a simple fix, and your car will be great again.

 

[radiovintageman]

Good advice, Uncle Benz! Very glad I joined the forum, you guys know Mercedes better than my dealer.

Good news about the SLK 32, and about our local independent, Nick Winter of the MB Centre Ltd (Nottingham). Nick rapidly found an air hose off (!) and the intercooler pump fuse blown. The hose had been left unconnected by the dealers after their expensive service. The blown fuse might just have happened spontaneously within the first 10 miles after the service - or not.
Oh, and it doesn't need a new oil level sensor fitted at £261.72 +VAT, but if it did Nick would charge me £115.

Took the car for a "remap" run and it settled down well, kickdown is right, and it goes like the rocket it should be. OK, I'll not sell it!

 

[television]

Good advice, Uncle Benz! Very glad I joined the forum, you guys know Mercedes better than my dealer.

Good news about the SLK 32, and about our local independent, Nick Winter of the MB Centre Ltd (Nottingham). Nick rapidly found an air hose off (!) and the intercooler pump fuse blown. The hose had been left unconnected by the dealers after their expensive service. The blown fuse might just have happened spontaneously within the first 10 miles after the service - or not.
Oh, and it doesn't need a new oil level sensor fitted at £261.72 +VAT, but if it did Nick would charge me £115.

Took the car for a "remap" run and it settled down well, kickdown is right, and it goes like the rocket it should be. OK, I'll not sell it!

Good news and good work, Uncle benz is very good with his advice

 

[Uncle Benz]

Great news!!

Keep an eye on that fuse. If it keeps blowing you will require a new intercooler pump. Not a huge problem, especially as you have found a good independent who, from the sound of it, knows a thing or two about AMGs!!

The pump is a common failure point on all the AMG supercharged cars.

From my investigations it seems the Bosch pump is designed for a vertical mounting, but space dictates that it had to be fitted in a horizontal plane, which wears one brush excessively...

 

[BlackC55]

There is a known problem with those pumps. There is a recomended repair method for them too. All available at main dealers.

 

[Uncle Benz]

There is a known problem with those pumps. There is a recomended repair method for them too. All available at main dealers.

I am not aware of any repair method other than replacement.

The pump has a non-contact magnetic drive impellor, and the motor is sealed - it requires a hacksaw to open it and get at the brushes.

An almost identical pump is used on the Ford F150 Lightening supercharged pick-up in the US. There is much discussion on the US forums about this subject...

Dealers like to suggest that bumper removal is necessary for this replacement, but a competent independent can do it through the wheelarch at much reduced cost. Some people have had success with warranty replacement at the dealers, but some have not - back to this old scenario!!...

 

[peter nicholls]

intercooler pump

I have just replaced my inter cooler pump and it only takes about 20 minutes to do don't forget to clamp the two water pipes so as to not loose to much water very easy to do

 

[BlackC55]

I am not aware of any repair method other than replacement.

The pump has a non-contact magnetic drive impellor, and the motor is sealed - it requires a hacksaw to open it and get at the brushes.

An almost identical pump is used on the Ford F150 Lightening supercharged pick-up in the US. There is much discussion on the US forums about this subject...

Dealers like to suggest that bumper removal is necessary for this replacement, but a competent independent can do it through the wheelarch at much reduced cost. Some people have had success with warranty replacement at the dealers, but some have not - back to this old scenario!!...

Sorry when I ment repair method I ment the dealers are aware of the problem and there is a recomended solution to the problem.:mrgreen: