Backfiring/Missfiring Fault

[Markbhai]

Whilst on my trip around Europe my 230SL has developed a fault.

I am finding that the car has very minor backfires (almost a popping sound from the exhaust) when I lift my foot off the gas.

In addition I am finding that I notice a mis-firing at around 2,500 revs - I have been driving the route Napoleon today and the car has been losing power quite sigificantly on the hills.

I have checked the leads and noticed that one of the spark plug leads was a very poor connection at the distributor - it had a green copper residue, which I have cleaned up back to the copper now with some sand paper.  the issue still exists though.

I can 'limp' home with this fault, but any advice of things to look for which i might try when out on the road would be helpful...or, if anyone knows of a good W113 mechanic between Grenoble and Nancy I could drop her in for a check up?

Cheers

Mark.

[jameshoward]

Are you on points or electronic ignition?

Are the leads OK? Assume it's not missing at all. Have you noticed a change in fuel consumption? Does it smell as if its running richer?

Is the dissy tight in its mount? Can you spin it at all by hand?

And, what tools, spares are you carrying? Have you got a plug spanner? If so, how do the plugs look?

A popping from the exhaust is OK when you have your foot off the accelerator.

[Markbhai]

Cheers...

Are you on points or electronic ignition? - Its a 230SL and I assume its electronic ignision as I can't see any points. - Bosch Distributor

Are the leads OK? Assume it's not missing at all. Have you noticed a change in fuel consumption? Does it smell as if its running richer? - Leads seem OK although the one which was gunked up does not have any solder on the distributor end (others do).  They all seem to fit ok to the plugs and I don't see any kinks etc. - The car has always had a soft fuel smell to it, I assumed this was how they smell - I haven't noticed it increase or decrease

Is the dissy tight in its mount? Can you spin it at all by hand? - Distrubutor is tight in the mount but I havent checked of I can spin it - by this I guess you mean can I spin the rotor arm...should I be able to?

And, what tools, spares are you carrying? Have you got a plug spanner? If so, how do the plugs look? - I have a socket set and screw drivers and pliers etc but no plug spanner so cant check the plugs.  I could look for a MB garage tomorrow.

A popping from the exhaust is OK when you have your foot off the accelerator.

[jameshoward]

All 113s were originally points. Are you confident to tinker? If not, find a garage. I wouldn't, though, leap to a MB garage. It's about the last place I'd go to. I'd suggest an old-fashioned small town workshop. It maybe that someone needs to regap the points and do the dwell, timing etc. My money is on an MB garage being no use at all.

When I say check the distributor, I mean grab hold of the body, so the metal part that the dissy cap clips on to and see if you can turn it. You shouldn't be able to. It maybe that your leads are knackered, though.

You should really get someone to take a look. It may be worth trying to see if a member who can help lives along your route.

[glenn]

Valves adjusted regularly?  Compression check?  Burnt valves?

[Markbhai]

The car wont start this morning so I have called out a mechanic.

The distributor is firm and doesnt move, checked the points and if I gently open them there is a spark, I have checked the leads but there is nothing notably wrong.

I think I have done all I can without parts and propper tools...looks like a breakdown truck home as I cant see a local having the knowledge to resolve this.

Oh well.

M.

[tel76]

Where are you located, there could be a member close by ?