2002 Peugeot 307 1.6 Petrol - Injector not firing, voltage? - HWLyon

Hi, I've been trying to troubleshoot a misfire/anti-pollution/cat converter fault.

I've read the code and it was a P0300, random misfire. I used HT testers to comfirm that the coil pack is working. I've had the ECU tested and confirmed okay by ECU Doctor.

I've pulled the injectors and can see that the one nearest the belts (Numbered four by the French I think) does not fire. I've swapped that injector with another and the fault does not move. I've continuity tested the wiring harness and the loom between the harness and ECU with a multimeter and they all seem fine.

I've also tried a different wiring harness but I get the same fault. If I move the harness to the left or right (connected to only three injectors) the fault always stays with the 4th position on the wirring harness.

I tried to take a voltage reading at each harness position with the DMM while cranking. While the results looked inconclusive, it did seem like the fault position gave a slighly lower value.

Not sure what to try next, how much voltage is required to open the injector? What could cause a voltage drop?

Hugh

2002 Peugeot 307 1.6 Petrol - Injector not firing, voltage? - injection doc

normally the telecametric relay, or multifunction relay or also known as the fuel pump relay.Often cause voltage drops.

Little orange coloured relay near the ECU has about 10 pins in it. If its orangny browny coloured its most likley the relay. Bout £20. new one will be black.

Ocassionaly the loom sufferes and rubs through internally on one of the bends near the bulkead..

also check the crank sensor signal with a scope. If the cycle is incorrect the ECU will shut the injector off to stop the cylinder flooding and causing damage to the cat.

often with PSA's you get inconclusive voltages at the injectors when testing and best to use a scope.

2002 Peugeot 307 1.6 Petrol - Injector not firing, voltage? - HWLyon

The ECU sits vertically in front of the fuses inside the fuse box. I had a look last night but doesn't see any relays in there, just fuses. The fuse box is Delphi.

2002 Peugeot 307 1.6 Petrol - Injector not firing, voltage? - bots
Hi am having same problem wth my 307 manual.did u manage with yours if u did hw did u do it thanx
 

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