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It could be possible they have spliced into it for an ignition live for something!?
Al have a gander tonight.
So if the ecu does not get a 12v input to pinout 37 is this why it stops injecting?
Sorry, it's says pinout 37 12v ecu input via s28 fuse am not sure if it goes from fuel pump relay 87a threw the s28 fuse then to the ecu or how it's wired
Thanks again
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So with ign on pin 37 feeds 12V to injectors directly and up to one side of fuse 28 which of course would be live all the way back to the relay contact 59. When you crank the signal should come from pin 3 to the fpr if the ecu is happy and that energises the fpr which then switch power to 87a back through fuse 28 to the injectors and pin 37!
Its needed basically for the output tests with ign on and to provide the burn off for the maf after shutdown.
Thats simplifying somewhat!
I'll will check as best as I can bt that seems right!
Fuel injection, fuel pump page shows pin 37 with a direct link to the injectors and also to D11 which is the switched +12v point in the front right wiring loom. this also branches to current tracks 16 and 35
Fuel pump relay page shows track 16 and fuse 28. Track 35 goes to the MAF (G70) and some other components. All the wires are blue / black for switched +12v
I am wondering if you have lost the feed from 87a to fuse 28 the other way which will be the other side of the fuse. That might account for why the voltage drops as it should be the fpr powering the injectors when you crank.
Anyway I'll see what I can determine factually.
Right Pin 37.
When I am refering to S28 I mean the rh side white fuse holder. When I refer to 1 or 2 contact its from left to right.
So Pin 37 goes through injector contact 2 to the S28 contact 1 (lh). The only continuity back to fpr 87a (59) is when there is a fuse in this position.
Fpr 87a (59) goes through S28 contact 2(rh). Again there is only continuity back to the injector and pin 37 when the fuse is inserted.
So thats why you could have power with ign on as its fed out of the ecu and not when cranking as it fed out of the fpr back to S28. As Newsh said it could be just a fuse or the contact 2 is not conected to the 87a terminal. If the fuse goes you stil have power at least with the ign on.
On an Aby the fuse box has a discreet 87a male terminal on the bottom. A female connector with 2 wires is fitted to it. One goes to S28 and the other S24. So I wonder if they have intercepted the S28 feed for the immo as clearly it would be an effective way of preventing the car starting! So perhaps that loose wire goes either to the S28 fuse holder or the 87a terminal depending on which side they cut. Would think the 3B uses a similiar if not identical set up.
Had the relay box out and the 87a did not have a connection to it.
This very suspicious 2x blue cables into one must of gone to it so someone has snipped it for some reason
I connected it up and she tried to fire up and the voltage at pinout 37 stayed consistent.
Now she tries to start but back fires alot can you confirm the firing order is 12453
And the dizzy ht plugs start cylinder 1 at the start of the lowest plug?
So happy wer getting some progress now
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