Stalling

[andrewofsoudley]

Hi All
220 coupe still stalling and does not want to re-start when hot, going to try a new fuel pump relay from Euromerc!

 

[kth286]

if you are new to Mercs I would find an Indie in your area familiar with the electronic Mercs of your geneneration and get the codes read.

It will narrow the search for the problem very quickly without too much expense.

OR

Look up the posts describing making your own code reader for under £10
and read the flash light codes yourself and post them up here for us to decipher them for you.

Just remember you will likely have an accumulation of codes stored from years of faults/service.

All these need to be cleared first, and car then driven to get the up to date fault codes.

 

[andrewofsoudley]

Hi

Thanks for info, kth286, fuel punp relay did not work! Going to Merc dealer in Shrewsbury tomorrow to pick up new OVP relay, £19 + VAT which I thought was cheap compared to second-hand ones on ebay at £12.50.
If that doesn't work then it's off to an indie, any recommendations in Shropshire/South Cheshire? There is a chap in Hadnall, anybody had dealings?

Thanks for help!

 

[grober]

The motorised idle control valve is supplied by the OVP so this may help. However this does not explain the reluctance to start when hot. This can be due to a weak mixture --- when cold the mixture will be enriched to aid starting. Have a look at the spark plugs for signs of a weak running mixture and check the inlet manifold for leaks.

 

[andrewofsoudley]

Thanks Graeme
Fingers crossed for new OVP relay tomorrow, need car to go to Edinburgh next week!
I'll keep posting.
Cheers
Andrew

 

[kth286]

the essential signal for the ECU is the signal from the crank sensor to tell the ECU the engine is turning over.

They can fail when hot, and can also get back into spec again when cooled down, thus allowing the car to restart.

 

[andrewofsoudley]

Hi Guys
New OVP relay did not work, car starts but cuts out when revs build, not all the time, seems to be when throttle opens a bit wider. Engine then splutters or cuts, sometimes with a small backfire.
When I was at Merc dealer I asked him to check part no of Fuel Pump Relay. The one fitted (and replaced) is A003 545 50 05, dealer reckons this is for a W202 (C180) not a W124 E220, don't know if this is a problem anyway, of to look at crank/cam sensor!
Cheers
Andrew

 

[kth286]

Now you have added that bit about sputters or cuts with a bit of backfire, it will probaly not be the crank sensor.

A faulty crank sensor will cut off the engine dead in a second.

 

[andrewofsoudley]

Hi Guys
I don't think I have correctly identified relays, the two I have replaced are behind the cover at the rear of the battery on the left (towards middle of car). The black one (Part no previously mentioned) and a green one with a 30A fuse on top, are these the fuel pump relay and OVP relay? Car is 1996 MY.
Thanks
Andrew

 

[andrewofsoudley]

Think I've found OVP relay!
Under black cover to right of ECU, tall silver 9 pin relay with 15A fuse on top!
Taken it out and sounds like something loose inside when shaken. I'll phone Merc dealer tomorrow to find out price of new one, part no 000 540 67 45.
Cheers
Andrew

 

[grober]

Think I've found OVP relay!
Under black cover to right of ECU, tall silver 9 pin relay with 15A fuse on top!
Taken it out and sounds like something loose inside when shaken. I'll phone Merc dealer tomorrow to find out price of new one, part no 000 540 67 45.
Cheers
Andrew

Yes you have found the OVP!
They can sometimes be repaired by resoldering contacts on the mini circuit board inside-- However-- rattling inside doesn't sound good. Your ABS light isn't on by any chance? Here's a piccy Mercedes Benz W124 Overload Relay 000 540 67 45 | eBay

 

[andrewofsoudley]

Still no luck!
Got new OVP relay this morning, fitted it and still the same. ABS light goes out as normal. When cold it seems ok, as soon as warms up that's when the problems start.
Going to try to get it in to a Merc specialist for diagnosis,so frustrating as when running sounds fine, full oil pressure and temp spot on!
Oh well, cheers
Andrew

 

[andrewofsoudley]

Hi All
E220 of to Merx in Stoke on Trent tomorrow for diagnostics, hope it's not too expensive! I'll post up how I found them!
Cheers

 

[grober]

One "off the wall" possibility is partial collapse / blockage of the catalytic converter but this usually accompanied by a drop in power throughout the rev range.

 

[andrewofsoudley]

Problem solved thanks to Vicky and the chaps at Merx, Stoke on Trent!
Wiring was badly routed and damaged to crank sensor, just picked it up and ran fine from Stoke through traffic to North Shropshire. Bit different to this morning, ended up with a tow from Green Flag to get there (Good Guys!).
Anyway Merx no is 01782 417720 website www.merx.gb.com
Off to Edinburgh on Thursday, that'll test it!
Cheers
Andrew

 

[andrewofsoudley]

Well, the saga contiues!
Merx did indeed fix the poor running, stalling,cutting out, however, a blast up the M6 and another problem!
After all the cutting out and BACKFIRING the cat is now shot! Apparently backfiring in the cat does not do it any good.
After a comfort break at Tebay I noticed a bit more of a rasp from the exhaust and the power dropping to such an extent I did not think we would get up the Beattock summit so abandoned car in Moffat and went to Edinburgh by bus.
Car now back in Merx via Green Flag (again, well done!) and awaiting cofirmation of diagnosis and cost.
Chin up
Andrew

 

[Terry_]

Absolutely chin up! It does seem a new engine harness is in order!!!!

 

[kth286]

Andrew

As a first off, just ONE thing needs doing.

The stored fault codes need reading and written down.

Then they need clearing, and the car needs to be driven until the problem appears again.

The codes then need to be read again and written down.

You then need to put them up here, and the collective on here will point you in the correct direction.

That's all you need to do at this stage.

 

[andrewofsoudley]

Thanks Chaps
I'll see what Merx say on Monday and post.
They have a Star machine but from the noise coming from underneath I'm pretty sure it's the cat. Don't seem to dear from places looked at on t'interweb!
Off to pub, has own microbrewery, three beers at £2.40 a pint.
Cheers
Andrew

 

[kth286]

a simple £20 vacuum gauge connected to the inlet manifold system
will show if the exhaust is blocked.

Halfords do those gauges with instructions.