Engine not running under load

[BigBen]

Hello,

Strange problem this week with my car (1989 Mercedes 300SL) after cranking for ages it will start and run perfectly even with some revs, however when I engage drive it will cut out before moving any distance.

First thought was a blockage in the fuel filter so changed this but no joy.

Other info is

-No smell of fuel from the exhaust after lengthy cranking
-After cranking on releasing the starter engine sort of runs to standstill, i.e. sounds like it has started but quietly
-Battery is charged and cranking is strong

Think that is all the information, can anyone help ?

Thanks

Ben

[BigBen]

Snake the Sniper said:

Sounds like the fuel pump's not doing it's job, or for some other reason, fuel isn't getting pressurised in the fuel rail. Does the fuel pump prime the rail when you first turn the ignition on? I had a car do this once, it would prime the rail, so it would start and run for a few moments, but would then just die away.
PS, you do have fuel in it don't you? Wouldn't be the first time......

Plenty of fuel in the tank (and I know I would not be the first)

I can hear the pump prime, off out in a moment to confirm it is actually pumping

To answer another questions it is a daily driver so is used a lot

Symptoms before the problem occured were a reluctance to rev, this happened about a mile from home and it made it all the way, at the time I thought a quick Italian tune up would clear any blockage, sadly not the case.

Ben

[BigBen]

Some progress, I have been able (in between rain and work) to remove the fuel feed to the fuel distributor and confirm that fuel is being pumped. Have also confirmed a spark. Therefore the problem is probably in the fuel distributor (Bosch KE Jetronic uses a funny fuel distributor type thing) Will look at that this eve

Ben

[BigBen]

Update on this over the weekend I confirmed that fuel was reaching the injectors and that I had some semblance of a spark, however the spark looked a bit rubbish so have ordered new coil, leads and plugs to see what happens

Ben

[BigBen]

To further update this I replaced the leads coil etc with no luck. Next I changed the dizzy cap and arm and it seems to have fixed the problem, annoyingly I had not really checked them as they were only fitted in January so assumed they were ok

Ben

[BigBen]

Pumaracing said:

Distributer caps are little bds though. They don't always show tracking marks inside even after they've failed. Always change them first if an engine starts playing up.

Dave Baker

I will next time