mobshop

My 560 sel will only start if I dose it with fuel through the intake. Once started it will run by itself but only over 2000rpm.I have replaced both fuel pumps and fuel filter. Very little fuel and pressure out of fuel distributer at cranking rpm. Any help will be appreciated thank you.

chassis

Fuel injection or carb? Trace all fuel lines and hoses. If fuel injection, try to figure out if the injectors are bad. Run the vehicle, and disconnect each injector electrical connector one at a time and see if engine performance changes. When there is no change in behavior, then replace that injector. Does the engine idle rough or smooth? Does it run rough or smooth at 2000rpm?

mobshop

Thanks Mate.I think I located the problem.The diaphragm in the fuel distributor has gone hard because of old fuel that has gone off.

gillarockus

Back to the point I verified the plug was sparking so I’m at a loss
all I can think is the injector isn’t firing correct
I bought a icarsoft mb11 and got the faults to clear
so when cleared it seems to idle better but still a miss.. SES light stays off for a while but it slowly returns the idle gets rougher and then the SES light comes on
now it’s just cyl4 miss with random misfires
still shows the “B camshaft position timing over retarded bank 1”
local MB says check compression possible bad head
so what is the correct process to accurately check compression on bank 1?
pull all 4 plugs throttle open ?
im new to this
can I just independently pull each plug and test that cyl the reinstall plug and move to the next ?
seems a low comp would be obvious
thx guys