Another Non Starting Gti6

[Clapton_Is_God 21 1 Cars]

Hello All,

 

The car turns over but won't fire. The fuel pump is running (it's very loud and maybe goosed after 8 years of non use) but there is fuel coming through the filter.

 

I've checked for a feed at the injectors and that's good but there is no feed at the coils.

 

Following advice on here I have checked for a switched live at pin 14 on the double relay and that's OK. I have checked for a permanent live at pins 2, 11, 8 and 15, all are good apart from pin number 2 which is dead.

 

Does anyone know what that pin controls or does? I thought I had a pinout for the double relay but can't seem to find it anywhere.

 

Any help would be mighty appreciated.

[dcc 855]

Have you remembered to plug in the crank sensor

[Clapton_Is_God 21 1 Cars]

Hello Dan, thanks for the quick reply!

 

Yes, just checked that and it is plugged in.

 

It's got me stumped!

[welshpug 1,627]

if there's no 12v at the coils I'd work back through the loom to the relay.

[Clapton_Is_God 21 1 Cars]

Good thinking, thank you.

 

I felt sure I had the wiring licked!

[Clapton_Is_God 21 1 Cars]

OK, it seems I had neglected to connect the wire from pin 2 so all is now good on that front.

 

However, I still have no 12v feed at coils and I'm wondering if it's perhaps a problem with the crankshaft position sensor. It was obviously working in the donor car, but that was a year ago. Can these things just fail when not in use? If so, is it a Peugeot only part or can I pick one up from a motor factors? My local GSF are less than helpful!

[allye 530 3 Cars]

You can pick up pattern crank sensors from ECP etc for cheap. I've changed a couple in the past but I don't they were the problem at the time! I'm sure you can do a test on them with a multimeter to see if it has broken down internally.

[welshpug 1,627]

crank sensor wont stop you getting 12v to the coil,

 

how are you checking it? from a pin to earth? or between the two pins?

[Clapton_Is_God 21 1 Cars]

I see, hopefully it's not that then.

 

Following advice from another thread I have checked it with the pin to an earth (battery negative).

 

I checked the continuity of the coil feeds from the ECU pins and they're all good.

 

I have no clue what's going on!

[Anthony 1,000]

Just checked against a spare loom and coil positive looks to come from pin 13 on the relay.

 

Is your injection relay defo known good?

 

If you get stuck I sometimes go through Wantage on my way home from work and don't mind popping over to have a look as I've done a few GTi6 conversions and have various spares for one.

[Clapton_Is_God 21 1 Cars]

Hello Anthony,

 

Thank you for checking.

 

I believe the relay to be good as everything was working fine when I removed it from the donor VTS but I guess it is possible that it's gone bad, it was a year ago I removed it. I understand they're quite common so I'll see if I can pick up a few spares from my local scrap yard as a quick fix and look into ordering a new one.

 

Your offer of help is much appreciated! I may take you up on that as wiring is not my strong point......clearly!

[Clapton_Is_God 21 1 Cars]

OK, so I managed to pick up a couple of relays from my local scrap yard (not ideal I know) and there's no change. I only get 0.1v at the coil when cranking. Am I correct in thinking that checking it when it's cranking is the correct thing to do? Or should I just see 12v with the ignition on?

 

I'm going to buy a crank sensor tomorrow, just to rule that out for certain.

 

I've had another thought though. I disconnected the ECU with the ignition on as suggested and I'm hoping that means it's unlocked. However, it has had a Superchip fitted by the previous owner, would that affect it in any way and prevent it from unlocking correctly? I hope not!

[dobboy 231 2 Cars]

Have you checked you have the fuel pipes connected the correct way round?

 

Seems strange it ran and now doesnt.

 

Trying a known unlocked ECU may be a good shout.

Edited March 22, 2016 by dobboy

[Clapton_Is_God 21 1 Cars]

Well it ran in the donor car, but not my 205 as yet.

 

I believe I've got the fuel lines the correct way round, there was a small leak from the top of the filter and I can hear it pressurising.

 

If the crank sensor doesn't sort it, I shall put out a distress call and hopefully Anthony or someone fairly local can help me check the ECU.

 

I'm having no luck lately :-(

[allye 530 3 Cars]

You could hear it pressurising with the lines the wrong way around. Happens to the best of us!

[Clapton_Is_God 21 1 Cars]

OK, good shout, I will double check that tomorrow.

 

I'm going to feel like a right plonker if that's all it is!

[ade 4wd 11]

Does the double relay click when you turn on the ignition? If yes, does the fuel pump run while the engine is being cranked?

There should be 12 volts at the coils (pin 2) and the injectors (pin 1) only while the engine is turning over. ie cranked or running.

 

If the above is all good and it will not start, then almost certainly the ECU is locked.

[Clapton_Is_God 21 1 Cars]

Good advice, thank you.

 

I THINK, I may have figured out what is going on. I stripped back the loom and discovered that I have connected the tacho converter to the positive feed for the coil and not the earth.......IDIOT!

 

In my defence, I started the loom and then got sidetracked with my dad being unwell and then went back to it several months later. Although I had Initially pinned it out, it seems the positive feed for the coil (pin 13 on the double relay) is a thick green wire and when I went back to it I mistook it for the earth.

 

Hopefully this will solve it. I'll confirm if it does in an effort to help anyone else daft enough to make this mistake.

 

Thanks again for all your help!

[Clapton_Is_God 21 1 Cars]

Update on my woes!

 

It seems I had cocked up the tacho convertor wiring and I now have a 12v spike at the coil when I turn the ignition on and 10.5v when cranking.......is that enough? The reason I ask is because I'm still getting no spark :-( Does the coil need the full 12v to achieve a spark?

 

I should add that the battery is good, I get 12v at the injectors, the fuel pump is definitely running with the fuel pipes the correct way round and the double relay is definitely clicking.

 

Assuming 10.5v is OK, crank sensor is my next step and then ECU.

 

I'm not having much luck this week!

[dobboy 231 2 Cars]

what's your tacho converter made up of? did you connect it like the little diagram i did on the wiring guide thread? iirc the "feeds" to the converter should be the side of the coils nearest the windscreen..

 

One wire from the converter joins on to the old rev counter wire (112 iirc)

Another wire tied to earth.

 

Sounds as though it is beginning to look like ECU.

[Clapton_Is_God 21 1 Cars]

Hello Dobboy,

 

Yes, I followed the guide on here and I'm confident it's correct now. I now have power everywhere I should, I definitely have fuel and I've replaced the relay and CPS to no effect. Anthony has kindly offered to stop by with a replacement ECU to confirm.

 

I disconnected it with the ignition on but I can only imagine it's not worked due to the fact that it's been messed around with (chipped) in the past. Time will tell.

[Paul_13 212 1 Cars]

I've had ecus randomly lock themselves after soft unlocking them

Edited March 30, 2016 by Paul_13