Lumpy tick over at low revs

[Liquid silver]

Hi All
I'm hoping somone can help. I have a problem with what I think is the fuel injection. When cruising at 50-70 all is well running very smoothly. However, when slowing down to a crawl in a traffic jam the reves drop almost to the point of stalling. Then when pulling away the revs do not build up as they should and it feels like there is a fuel starvation, then when reving hard it backfires and clears whatever blockage was there, pulls away and cruises normally. I know the engine is running rich (I believe it is a known common problem) from the soot in the exhaust. Anyone else had a similar problem and how did you solve it.
Many thanks for any suggestions.

Paul

[Larry & Norma]

I would do the 'linkage tour' and set up the idle using a CO metre if possible. Idle adjustment is
described in the Haynes manual. My car was very sooty at idle before I did this, incorrect idle adjustment
is very common.

[jameshoward]

Low revs = need to attend to the linkage, just as Larry says. Great advice.

I had exactly this issue and it took me a few goes at the tour, so you must view the tour as an art not a science. It can take a view goes to get it right. It sounds like a mixture issue to me. Given you've just got the car, you may want to get together a few parts in preparation, such as plugs (do research), wires, dizzy cap, rotor arm, points. All cheap stuff and so a good place to start to baseline your investigation.

[Liquid silver]

Thanks guys. I will be taking it to my Indie next week sounds to technical for a numpty like me.

[jameshoward]

OK. But don't be too quick to take it to an indy unless they know the cars. ie REALLY know the 113. A bit or reading here on the wiki plus the investment of a bit of time in your car could well reward you with (a) a better outcome than an indy could offer and, (b) less money spent.

The process described in the wiki is super basic. Give it a go and get to know your car would be my advice.

Either way, good luck.

[stickandrudderman]

Indeed, not all indies are the same!
 

[jameshoward]

Indeed, not all indies are the same!
 

Poor phraseology on my part, forgive me. I interpreted that to mean someone who wasn't an MB specialist, unlike your good self, Colin, noting that you are also an indy. Think "Joe's Car Repairs, 23 Railway Cuttings, East Cheam," - fix it while you wait, etc.

[Liquid silver]

Indeed, not all indies are the same!
 

You are right about that. The Indie I use in Nottingham is very good,trust them totally with my 107. Recently had a fuel pump relay go on me. Most would order a new one at a cost of approx £190.00 they opened it up, repaired it, no charge. The guy that works on my 107 worked on them when new so is what I call a proper mechanic. Going in tomorrow so hopefully all will be OK. Will keep you updated. Not too sure about the MOT as the car is left hand drive with red rear indicators, km speedo and dip right headlights. Fingers crossed

[AGT]

Beautiful looking car.

Are you going to get your Independent to present your car for MoT to his "local"?  I had my straight off the boat US spec 230SL registered and MoT'd in the UK for five years and had my Independent deal with the MoT every year as part of the annual service. The relationship with the MoT tester might help and some testers like to see a well maintained classic fresh from its annual service. I suppose one thing to try to avoid here is a fail with the car then being on the system with the reason for the fail needing to be rectified.

On your specifics:

- I think that you are correct about the colour of the indicator lenses but would be amazed if this was picked up. I never had a problem on this point;
- the speedo needs to work but I am not sure that it has to be in MPH. I also think that if you have a sat nav connected with GPS then that is sufficient;
- the dipped headlights are so feeble that you will be hard pushed to tell whether they dip right or left. As you will know from your modern cars xenons don't dip right or left, they just lower and that might be all that the tester looks for. You can't tape the lights up when you present the car and this would draw unwanted attention to the issue!

Very best of luck. Let us know how you get on.

Regards
Andrew

1966 230SL
1989 420SL