My partner's 2001 Mk1 1.4 16v AUB Fabia has been diagnosed by the RAC as having an issue with no.4 Injector so we're looking at an ECU problem or wiring snag. I'm thinking wiring is more likely the issue but I'd like to be able to confirm the wire colours/pins for No 4 injector at the ECU please? 

Weirdly enough I had a similar problem with the no 3 injector switched earth in April 2017, I slaved in a new bit of wire and it's worked well ever since.... Hoping for a repeat, today if possible as its not raining!! 

Edited 2 January, 20233 yr by colinstubbs

I think you'll find the 12V feed is the same volour on all four, and comes from a fuse rather than the ECU. The wire colour of the switched return from each injector will be the same at injector connector and engine ECU as it's a direct run. Will confirm in a few minutes, with ECU pin number.

Here you go, what I found for you.

 

Injector 4 should be Purple/Blue at T40a Pin 89 (verify with the other injectors/colour/pins)

 

Cheers peps, great help ta!! 

😉 

Well all the info was good (and the fault disappeared for a while but its back) but instead of proving the earth was faulty, as previously on cyl 3, so I could slave in new wire, I've been able to confirm the earth wire as good and good supply voltage to the other pin. So I'm looking at the injector or the ecu at fault I guess? 

Injector resistance was 16ohm which I believe is about right? Thinking it needs a trip to the garage. Partner needs it quite urgently now. 🙄 

Test sequence
– Check resistance of the individual injection valves.
Specified value at 20°C: 14.0...17.0 Ω

 

If the engine is warm the resistance increases by approximately
4 to 6 Ω.

 

 

Hopefully that helps verify.

Cheers all, turns out it was crap replacement HT Leads which happened to affect the same cylinder!! Still, trip to my usual garage confirmed the issue  and sorted that and the dicky oil pressure switch that had literally just started playing up and while they had it I got them to change the thermostat I was gonna do myself so all was good. 

No issues since, touch wood! 

Youngs Garage

Gasoline Alley

Wrotham 

🤘😉👌