The engine will not start

[Stormen]

Hello

I have a problem with my 500e 1993.
When I tray to start it the fuel pump doesn't start and the injectors doesn't open.
I can se that it missing the control unit for the alarm.
I have changed the wiring on the engine.
I company check the Lh ECU and it's ok.
Fuel pump is ok.
The engine starts when I put some gas in the intake.

What is the problem
Please help me

 

[Duh_Vinci]

Cheers!

Would this thread be of any help with your issue (fuel pump relay or EZL issues by chance) the car cranks but does not start ?

Regards,
D

 

[gsxr]

If the fuel pump doesn't run, that is the problem. The pumps are fed from the green relay below the passenger rear seat cushion, the relay is triggered by the LH module. Check the relay & fuse if present. The relay almost never fails. Try a different LH module if you have one handy. As a test you can bypass the relay and force the pumps on. If the pumps run and the car starts, the pumps are ok. If you bypass the relay and the pumps don't run, the pumps may be faulty.

 

[Stormen]

Thanks for responding.

The pumps works when I bypass it. But the engine dont start.
The engine starts when I but som gas in the intake.

 

[gsxr]

The pumps works when I bypass it. But the engine dont start.
The engine starts when I but som gas in the intake.

Check fuel pressure at the rail service port. If there is pressure with the pumps running and the engine does not start, the problem is with the computer controls (LH, EZL, etc).

Have you checked fault codes?

 

[maw1124]

Check fuel pressure at the rail service port. If there is pressure with the pumps running and the engine does not start, the problem is with the computer controls (LH, EZL, etc).

Have you checked fault codes?

+1 on LH if it hasn't been rebuilt yet. Those seem like "when" items more than "if" to me. I actually had a problem with mine very early after I bought it, on a 60k mile car. So I consider them time not mileage issues, although that's crude science.

FPR is on my mind as well but the check at the rail will clear that and weak / failing pumps. They could be working but on their way out.

maw

 

[sheward]

I actually did have a faulty relay at 60,000 miles. Easy and cheap to try.