Welcome back to my nightmare! Just to remind readers, it's an April 1998 mini-facelift 3.0 Omega Elite Estate. I bought it with a duff ABS ECU and a blow from the exhaust. I drove about 30 miles trying it out and it ran fine on petrol and LPG. So I then fixed the two major faults. After much work, new oil, water, etc, all ready to fire up -and nothing. No spark. Paperclip test shows 19 -interruption/failure? of crank sensor/circuit. No other faults show, not even 31, engine not running.
So I buy a new crank sensor and fit it. Still no joy. Realise that 19 is "interruption of rpm signal" according to Haynes manual, so I do a continuity test on the wires that go from the sensor plug to the ECU. Brown, grey/red, grey/black. No continuity on any of the three wires. Strange. So I think, well, I moved the big fat loom around while doing the ABS ECU, so maybe I have disturbed the wires -maybe even broken them. Also realise that LPG ECU must need the same info, so there must be a takeoff from the wiring somewhere for that. A plug maybe? Have I left it unplugged?
I search high and low for a missing plug, and can find nothing. However there is a loose plug over by the LPG ECU, the plug is the crank sensor type, and it has three wires -blue, brown and white. White rings a bell -it is shown in a back-of-the-envelope schematic diagram of the LPG system that came with the service history folder. White wire for rpm signal. Looking at my photos of the engine bay before I started the major work on it, it shows this wire disappearing under the scuttle cover just by the brake cylinder. But I can't find anything for it to plug into. I have searched and searched. The three pins in the plug look dirty and unused. So I assumed that this lead and plug was redundant and just stuffed under the scuttle out of the way. See third photo below.
Eventually I decide to connect the new crank sensor directly to the engine ECU, as in the photo below. I adapted a crank sensor plug off a scrap Carlton, and wired it directly to the ECU pins 19 (earth) and 48 & 49 (grey/red, grey/black). The original wiring was left in place, other than disconnecting the original female plug. So any taps into it for the LPG etc are still there. My new wiring simply bypasses everything.
The battery is disconnected all this time of course, so the original fault code should have been cleared. Switch back on, knowing that crank sensor is now firmly connected to the ECU and guess what -still fault code 19! Still no spark! (Go to next paragraph below)
My new wiring. Of course if the Omega deigns to start, I won't leave it like this, it will all be tidied up neatly.
General view of the engine bay.
Here is the mysterious plug branching off from the LPG ECU wiring.
Here is the LPG ECU.
So I am now at my wit's end. I just cannot figure out what is wrong. I have also tried it with the LPG ECU disconnected -same result. Whatever I do, the car tells me I have fault 19. Still no spark.
If anyone can shed any light on this, I will be eternally grateful, because at the rate I am going, this car will end up in pieces on eBay. That would be a shame, because I really need this capacious, 3-litre estate to work for me, so that I can visit my family in Essex without having to sell my soul for petrol. There is also a good chance that I will slash my wrists, as the car has cost me a fair amount in parts and time that would otherwise have earned me money restoring Monzas.
In fact if it ever runs again, the cost will have far outweighed the saving in LPG over petrol!
Help! I'm sure that I have done something silly, like leave a plug disconnected, but I just can't see where, and I have searched all over this engine with my halogen head torch in the dark (the best ever way to spot rust under a car when thinking of buying -look at it in the dark witha halogen head torch).
Any ideas are welcome!
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Topic: Coolant Low - SAFE showing on display -won't start (Read 4048 times)