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Re: Hello Chaps....new owner

Posted: Wed Mar 17, 2021 5:33 pm
by ralphturenne
Hello Guys,

I am still having issues keeping my car running. the injectors are not receiving electrical current that will allow them to work. When you pour gas in the intake it works well. I send the docs and electrical schematics to a guy he told he is pretty sure it has to do with an electrical part in one of the doors. seems like its a safety devices (not so sure) I still think its either that or something else. Any suggested step by step would be appreciated.

Re: New owner with Series 1.

Posted: Thu Mar 18, 2021 6:46 am
by Dieselman
The injectors (570) and fuel pump (755), are fed +12v directly from Relay 807.
Relay 807 receives its main power straight from the battery and the +12v trigger from the ignition switch. It also powers the coil and electronic ignition, which must be working for the engine to run.

The fuel pump (755) has a direct connection to Gnd. Can you hear the fuel pump running? Have you tested the +12v feed and the Gnd with a test lamp?
You could disconnect the fuel feed pipe at the pressure regulator, face it into a bottle, and see if petrol is being pumped. Be aware of fire risk.

The injectors are fed a constant +12v on one terminal and are switched on/off by the Ecu shunting the other terminal to Gnd. Have you tested the +12v feed and the Gnd with a test lamp?
You can check the resistance of the injectors using a DMM. They should be approximately 16 ohms, each, both cold and hot.

The doors are nothing to do with the injectors running, or not. The door lock quick sets the immobiliser when locking, instead of waiting for it to time out.
The immobiliser keypad will stop the engine running, but I assume you have the code and the green light on, as the engine is running if you manually supply it with petrol.

Trace the circuit and test for voltage and good Gnd connections using a test lamp.
The connection pins for each connection are numbered on the circuit diagram.
The wire colours are given, but be aware they are in French...Bleu = blue, Jaune = yellow, etc.

Have a look at the circuit diagram and info, perform the checks advised, report back your questions, findings and any other info you have, such as the immobiliser status (red or green).

We can help you, but only if you keep coming back to us.

Re: New owner with Series 1.

Posted: Thu Mar 18, 2021 1:59 pm
by ralphturenne
thank you, the pump works fine. I made a small video that i am unable to share because of its size. I am trying to edit it. I will try what you just told me and report back.
thanks again

Re: New owner with Series 1.

Posted: Fri Mar 19, 2021 7:25 am
by Dieselman
Using the Blink Code Reader, you can perform a number of engine component tests, one being to pulse the injectors.
You can hear them pulse which should prove they are receiving +12v and the Ecu can control them.
Don't perform the test more than twice, as it squirts fuel into the engine.
A cheap fuel pressure gauge is invaluable for monitoring the fuel rail pressure and checking if the regulator is working properly.

To check the injector electrics operation, a 8 watt lamp could be substituted.

As already mentioned, the fuel system primes for 1s at Ign on, then once the Ecu sees the starter "crank" signal it switches to running mode.
The crank sensor tells the Ecu that the engine is turning and gives the timing signal.
It sounds like there is no crank signal...but Afaik the Ignition system also relies on that, in which case it has to be working.
Is the rev counter working? That relies on the crank sensor output.
A cheap digital oscilloscope could be used to monitor the crank sensor output, if necessary.

If the injectors are just seized shut, the can sometimes be brought back to life by feeding them On/Off 12v pulses direct from the battery.

Read the codes with the Blink Code Reader, there may be some info there.

You might find it easier to dismantle the Ecu 55pin connector and probe into the back of the pins, than trying to connect into the individual component connectors, while they are connected.
This is also a good place to check the Ecu is seeing all the required inputs.
Check the Ecu has all the necessary power and Gnd feeds it needs to operate.

A couple of threads that go into some detail on V6 diagnostics:
http://www.club-xm.co.uk/forum/viewtopic.php?f=19&t=125
http://www.club-xm.co.uk/forum/viewtopi ... =19&t=8535