H E L P to

[mercman1969]

Diagnose my misfire and rough running on my W163

Tried throwing up a couple of threads without a single response

Need to get this sorted ASAP so it is safe for my wife to transport our 3 year old to nursery

Was going to simply change coils & leads but having spoken to somebody today they said it could be an ECU problem and to have it diagnosed

Dont want to hand it to the stealer to charge me the earth for a couple of hours of software running whilst he drinks tea

Anybody close to Grantham in Lincs who could help me out

 

[Dieselman]

Previous thread.
http://www.mbclub.co.uk/forums/showthread.php?p=645654#post645654

The interference does sound like an HT leak, the symptoms fit also.
Try running the engine at night in a dark area and looking for tracking and inspect the leads and connectors.

 

[mercman1969]

Previous thread.
http://www.mbclub.co.uk/forums/showthread.php?p=645654#post645654

The interference does sound like an HT leak, the symptoms fit also.
Try running the engine at night in a dark area and looking for tracking and inspect the leads and connectors.

I had it looked at whilst having LPG serviced by a chap and an occiliscope

he found that the plugs - well 10 of them were double firing
the burn was good on the plug
the coils looked a little weak

the 'double burn' is somewhat confusing to me....why would it fire twice

 

[Dieselman]

Doesn't he mean both plugs per cylinder were firing.? In which case that's right.

If 10 were the same and 2 different then they are probably the problem ones.

You could obtain a cheap flash tester and check the spark strength.

 

[mercman1969]

Doesn't he mean both plugs per cylinder were firing.? In which case that's right.

If 10 were the same and 2 different then they are probably the problem ones.

You could obtain a cheap flash tester and check the spark strength.

thats what i thought....if 10 were fine then that would equate to 1 cylinder mis firing?

He had run a tap from the back of the coil into his equipment....cant recall but think he selected 2 seperate cables from each coil

if that is true then was he testing each plug seperatly or was he checking low and high tension?