W220 sudden power loss

[matthewm1965]

W220 S500
Driving to work this morning down the A1, behind a wagon, lots of spray. Sudden loss of power, wouldn’t go above 55 mph. The engine was misfiring badly if I tried to accelerate. I carried on for about a mile until it was safe to pull onto the hard shoulder. Switched off and waited 30 seconds then re-started. It started and ran perfectly for the rest of the journey.
No error messages were displayed when this happened. I am guessing that all the spray had maybe caused an HT lead breakdown and caused it to go into limp mode?? Wouldn’t this have caused an error message? Or do I need to get it on star to see if any error codes were generated.

Matt

 

[47p2]

No error will show on your dashboard, I'm affraid the car will need to be connected to star to diagnose the problem

 

[television]

I think that the MAF is at fault here,,it is one of the only switchable things

 

[matthewm1965]

Would a collapsed cat give the same symptoms? I have noticed a rattle develop from that area over the last week.
It struggled going up hills tonight, not wanting to go much over 2000rpm.
Matt

 

[47p2]

Try disconnecting the plug that goes into the MAF and see what happens

 

[MB Service Centre]

Cat can cause problems, but dose sound like the old air mass problem,
If it was something like you said i am sure you would prob get engine management light on the dash.Where abouts in durham do you live? thats my home town but now live in nottinghamshire, i might be able to recomend someone to you.

 

[teabag]

Cat can cause problems, but dose sound like the old air mass problem,
If it was something like you said i am sure you would prob get engine management light on the dash.Where abouts in durham do you live? thats my home town but now live in nottinghamshire, i might be able to recomend someone to you.

These guys are not too far away from Durham and I've found them to be very good. www.prestigeservicing.co.uk

 

[matthewm1965]

These guys are not too far away from Durham and I've found them to be very good. www.prestigeservicing.co.uk

They are about 2 miles from where I am working. I'll give them a ring and try and get it in tomorrow and get them to plug it into Star.

Thanks
Matt

 

[teabag]

They are about 2 miles from where I am working. I'll give them a ring and try and get it in tomorrow and get them to plug it into Star.

Thanks
Matt

Once you get to know them, they will drop you off at work and pick you up again when the car is ready, Tell them Peter from Tetley sent you.

 

[matthewm1965]

Try disconnecting the plug that goes into the MAF and see what happens

I diconnected the MAF connector, which enabled the engine to rev above 2000rpm. This enabled me to drive the 30 miles to Prestige Servicing at Stockton where it was plugged into Star.
So far it looks like the RH cat has failed, probably caused by a missfire. Air flow and RPM sensors also showing faults.
They are going to replace the cat then further investigation to find the cause of missfire.
I'll keep you updated
I can feel a second mortgage coming
Matt

 

[matthewm1965]

Update

Got the car back last night.
It needed two new cats and MAF sensor
Thanks for everyones help, especially Peter for suggesting Prestige Servicing at Stockton. I'll be using them again when I need them.
Matt

 

[television]

Thanks for posting back,, none to cheap but it is working again These things happen

 

[Chas]

Got the car back last night.
It needed two new cats and MAF sensor
Thanks for everyones help, especially Peter for suggesting Prestige Servicing at Stockton. I'll be using them again when I need them.
Matt

How much did it cost you for the two new cats and MAF sensor, if you dont mind ?

 

[matthewm1965]

How much did it cost you for the two new cats and MAF sensor, if you dont mind ?

I don't have a breakdown of the bill in front of but going from memory, the cats were pattern parts not MB (is that the correct term?) and were aprox £360 each as opposed to nearly £700 each for original MB. The MAF was approx £160.
The garage also noticed that the front brake discs were worn to a dangerous degree, which didn't supprise me as they were very noisy. This added an extra £300 to the bill. So all in all an expensive do, but would have been twice the price if I had gone to a main dealer outlet! At least I know it should be ok for a bit longer.... Fingers crossed!

Prestige Servicing at Stockton strike me as a very professional outfit. They were very busy, working til 9 in the evening due to all the work they had, but managed to fit me in when I just turned up on their doorstep, and gave me a loan car for the week. Rang me up regularly with updates on what they had found and how much it was going to cost. I'll be using them again when the need arrises.
Matt

 

[teabag]

Prestige Servicing at Stockton strike me as a very professional outfit. They were very busy, working til 9 in the evening due to all the work they had, but managed to fit me in when I just turned up on their doorstep, and gave me a loan car for the week. Rang me up regularly with updates on what they had found and how much it was going to cost. I'll be using them again when the need arrises.

I'm pleased you found them to be OK, as I said earlier, I have been using Kevin and Tony at Prestige for 3 years and they have always provided an excellent service.

You did well with loan car though as I have had to hire from "Enterprise" around the corner when I have been stuck in Stockton.