Starting probs - 1988 260E

When does the delayed start occur? Cold engine? Hot engine? All the time? How many miles / kms on this engine? Anything recently happen?

thanks this seems to happen when it's both a cold start and hot start - it seems to be all the time, though between breaks it occasionally starts on first turn the engine has 250 kilometres on it and has been regularly serviced nothing major has happened recently

peter

The fuel pressure ought to be the initial line of inquiry. There's a fuel pressure regulator that, as its name implies, regulates the fuel system pressure to a specification. Then there's the fuel accumulator and two electric fuel pumps, all back at the fuel tank.

Fuel system pressure and volume can be tested so there's no reason to speculatively replace these expensive parts only to find no improvement after your $$ have been liberated from your pocket. Suggest you have the fuel pump pressure checked in line with the starting problem.

Peter,

When the car finally starts, do you see black smoke buff? If so, it could be your injectors or cold start injector leaking. Also check the air flow sensor plate rest position

Please tell me know how do we look or check the air flow sensor plate? If we nerver adjust it, does the position changed by itself ? Thanks! Quang

Have the fuel pump or fuel pump relay been ever changed ? Quang

Hi Peter , I have the same problem, After changing the fuel pressure regulator, fuel pump relay, high Vottage protection, problem still there. Finally, bring to good mechanic, he find down the cold start valve is leaking! And the fuel accumilator is bad! He also suggest to changed the 4 fuel injectors (150km). And now my car is good to start now! Good luck to you! Quang