E320 CDI Estate locks in '2' intermittently! HELP please!

[sevener]

Hello everyone - first posting but I've had a good look around to see if my exact problem has been dealt with before... without any success. Treat me gently, I'm not a mechanic :Oops:

About a week ago our "X" reg 320 CDI Elegance Estate locked into 2 (max 45mph-ish with around 3,500 rpm. As I came round a left-hand bend on to a slip road, I overrode the box into tiptronic 3 (or so I thought) and it just stuck there.

Having already had one limp-home moment a couple of years ago, I wasn't keen to stop and switch off, so drove very gently all the way home at 45. Not a happy experience! (Previous time it was the ECU fuse, so we carry a spare. Tried that but no difference.) No malfunction showing, except when you try to engage cruise - it then says "speedtronic - visit workshop".

Switched off at home. Started up and no faults! Car was fine. Next day, the car is OK for a few miles, then goes into 'limp' mode. Visit dealer. No fault showing. They keep car for a few days and their technicians can't make it replicate the problem. I go over and drive around for 30 miles and I can't either! Bring car back home. Their advice is to switch off and the problem will clear. Go out yesterday and the problem comes back. Go in to layby, switch off. Wait. Start up again and the problem is now there all the time. No malfunction warning comes up.

Any ideas?

The car has done 120,000 with main dealer FSH and until now, we've been really pleased with our 'luxury dog wagon', but you can't get all the shopping in our other car which is a Caterham :grin:

TIA
Sevener

 

[jberks]

If the problem is now present permanently, it should be pretty easy for the mechanic to diagnose it. Bob it back to the dealer.
That said, as you're new here, I'll give you the standard advice. Yours is a 2001 S210 so it is wise to keep the main dealer service history to maintain the corrosion warranty, but there is no reason to pay out £100+ per hour for basic diagnosis work when your local MB specialist will do the same work for less than half the price. I don't just say this for financial reasons, but the dealer mechanic mainly works on newer cars so is not that experienced on the slightly older higher mileage ones, whereas your specialist will be working on them every day and so is actually far more likely to know what the problem is and the best way to cure it.

 

[Blobcat]

Hi & Welcome,
If the car has gone into limp mode and when trying to apply cruise 'Speedtronic - Visit workshop' is on the display fault codes will have been logged. Since it is now in permanent limp mode I would have the codes read and then post them up.
It doesn't sound like a MAS problem, however when was your MAS last changed?

 

[television]

I think that there is a good chance that it is the MAF, cant check further till next week.

Malcolm

 

[sevener]

Thanks for the tips so far The car is booked in for next Thursday and we'll see how things go. Unfortunately, even when I previously pushed the 'cruise/limit' control and the speedtronic, visit workshop was displayed - it didn't store anything for them to download or analyse :-? MAS/MAF have been checked and aren't the culprits, according to friendly workshop manager.



At least the weather's reasonable, so I get to play in the Caterham

 

[malcolm E53 AMG]

Hi severner,
I know it sounds basic but has the battery been changed since the car was new. I was experiencing spurious electrical problems just prior to the battery failing last year. Changed the battery and all was well, low voltage on these cars results in systems shutting down with no obvious cause.

If you still have the origiinal battery fitted it will be ready for changing,

Hope this helps.

 

[sevener]

Ok folks - an update. Just received a call from workshop manager. The fault has finally shown up and the car needs a replacement electro-hydraulic control unit :sad:

 

[television]

That's a kind of good news, you could ask them how much, and then ask a indie gearbox repairer.

Malcolm

 

[rajinder_1]

Or get the part number and try

http://www.mercedes-benz-parts.co.uk/

are usually cheaper than the dealer on alot of parts


Raj