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Discussion Starter #1
I been troubleshooting a non starting spider 85 (l-Jetronic) the fuel pressure is good, and the injector connector are pulsing my diode (test light) for the injectors.
It seems like the injectors are not spraying. In fact I have removed injector (#4) out of the head and see if it would spray during a crank, but nothing happen?
So I assume the injectors are bad, the car has started 2 days before just fine.
The spark plugs are good and they spark plenty.

Anyone has an opinion or suggestion??? :confused::confused::confused:
 

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It would seem unusual that all 4 injectors would quit at the same time.

How are you measuring fuel pressure?

Have you seen this page: L-jet Spider diagnosis ?

The section about the fuel pump operation needs to be edited. The correct info is as follows: the Drive Relay (near the FI ECU) gets a signal from the coil. When you first switch on the ignition, the drive relay sees that brief signal and sends power to the fuel pumps for an instant then stops sending power (no more input from coil).

During cranking (and running) the ignition pulses to the drive relay trigger it to send power to the pumps. Thus, a functioning ignition system is required for the drive relay to get a valid signal and send power to the pumps.

I'm not sure off hand if/how a problematic drive relay would affect injector function. But I'd suggest looking for info about that before condemning the injectors.
 

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I'm not sure off hand if/how a problematic drive relay would affect injector function.
Severly actually.

If the drive relay is not functioning correctly, then the trigger signal to the main relay may not be getting sent through or is intermittant.

Net result: no injector function.


Drive relay supplies constant + power to the injectors when activated, while the actual squirting is controlled by the ECU interupting the ground circut.

Of course it could be just a case of the fuse back there being blown or in poor shape.
 

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Discussion Starter #4
Tifosi, but i used a diode on the injector connector and i see the pulse from the ECU. So i think I am getting power to the harness connector. I agree, its unlikely that all 4 injectors are bad....but, what else could it be?

I pulled the injector out and no Gas is been sprayed while cranking. Fuel pressure is pretty high in the rail.

Any suggestions?
 
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