filipharvey

Just removed plenum, no sign of split wires there. If I disconnect all 4 lambdas, the faults still say invalid signal - surely it should change to no signal? Only the precat lambda on bank 2 changed its status to that.

Ok, well the front cover is off - has been for some time. I'll take the plenum off tomorrow and check for any signs there. Unlikely that I'll be at SAD.

If the lambda alone is unplugged, no it doesn't clear. Plug B has to be removed from the ECU itself for the fault to clear. Yes, have tried another MAF. The ECU is earthed to the body as it was relocated to the bulkhead when I put the 3.0 in. The earth leads to the block and cam covers are good too. Not sure where to check the earths to the sensors themselves though? Thanks mate

I'm aware the engine won't start, but my thinking was that as the fault shows even with the engine off, and reappears as soon as plug B is reconnected to the ECU (it won't clear with it connected) then I don't need to go as far as starting the engine with a different ECU. However, if you think there is a chance of blowing another, I won't try it. I do think that the shorting lambda wires are the likely cause though, and that has been sorted. I have swapped all of the relays in front of the battery around, and the fault still shows. I know you really need to see it hands on, but you are a long way from me. Is there anything else I should be looking for diagnostic wise?

Well it is all back together and the fault is still there, so it must be a fuse, relay or the ECU. Does anybody know where that fuse/relay is???

Well the exhaust splitting may well have been a good thing! During all my fiddling around, I had only checked and cleaned connections, not the wires themselves. Whilst I was under the car removing the downpipe, I noticed that the front in-cat lambda wire was split - both white wires. Those are the two that power the lambda heater, and by the looks of it they had been touching where the bare wires met. I'm gonna take a wild guess, but I reckon this is the cause of all my problems. So, what I need to know is; a ) Where is the fuse for the lambda heaters? b ) Is that fuse shared with the MAF or EVAP control? I've checked most of the fuses above the main fuse box by the driver's knee, but they all seemed fine. I'm hoping that there is actually a fuse for them, otherwise this will definitely have goosed the ECU!

I'll have them off you if you can find them. I'll probably be able to get these patched up for now, but the flexis weren't brilliant when I bought them from AL, so a spare set will be handy.

Was expecting it to be the flexi, but no, the actual pipe has split all the way around the weld.

Yes, they are CF3 downpipes mate.

Well Casson has said I can use his. But to top all this off, I just went down the road and one of my down pipes has split. Bollocks!

That's even better being a 156, although it doesn't really make much difference if I'm putting your ECU on my car rather than the other way around. I'd be happy to meet you somewhere, but I'll see if Jim will do it first. I'll get back to you once I've checked the pinouts and I'll have a word with Dan to make sure all was ok when he tried it.

Thinking about it, I'm sure Dan said he has used an ME3.1 on a GTA to see if they could be used instead due to the GTA's failure rate and rarity, and it was fine other than a few fault codes. I'm almost certain the pinouts are the same, but I will double check. Whereabouts are you anyway mate? 156 or 147 GTA - can't remember what you've got!

Will do. I might have a word with Casson as he's probably closer than you - but he's fairly precious over his GTA so probably wouldn't allow it

If the pinouts are the same, it would be enough to test it. The ME3.1 of the 2.5/3.0 and ME7.3.1 of the 3.2 are near identical ECUs. I'll have to check.

Think I can get a set from AL for about £160, so it's not too bad. Just don't want to buy one to find out that wasn't the fault after all. I do wonder if either the 3.0 GTV or 166 codebox will work on the 156? The ECU will as they are all ME3.1's but I would need the codebox and immobilser chip to match. It would save me getting a remap on a 2.5 156 one.