So I managed to get up to look at the car yesterday armed with my brother (the mechanic one), a selection of tools (particularly a multi-meter) and (on the advice of the mechanic 'friend of a friend' who has been looking at the problem) a spare Crank Position Sensor or CPS (but from a 940 turbo).
After checking what had already been done and a few false leads (the other guy wasn't around) I found the Owners Manual … which we quickly exhausted! A bit more digging found my trusty Haynes manual, which was more helpful.
The CPS on the car seemed to be faulty – not 220 Ohms +/- 60 (thanks Mr Haynes)– but we were unsure and moved onto the EFi Control Relay wiring anyway. This was OK until we got to an ignition signal which didn't look like the 'flashing' output expected (we were using the multi-meter rather than the test lamp suggested) but, not fully understanding the system, we weren't sure why that would prevent fuel and spark.
Following through the block diagrams and control relay pin-outs we managed to get the fuel pump 'ticking' but no spark, as per the previous attempts. From experience, my brother had suggested the overall fault could be a triggered 'inertia' / crash switch but no amount of 'Googling' had found any mention of one being fitted on a 360. A mental leap then got me wondering if the lack of an ignition signal would stop the fuel circuit energising as a 'feature' of the EFi. I knew from researching 340/360 EFi problems hereabouts that a faulty CPS would completely stop the Renix producing any spark so, logically, it wouldn't stump up a 'flashing' ignition signal either (assuming that was where such a signal would be produced). Haynes was unclear but this is backed-up by Ride_on, in answer to my related question over on the engine technical thread; unfortunately I didn't see his answer before setting off
So much for the theory but how to confirm the fault?
This is where the 940 CPS was supposed to come in but, unlike me (beforehand), those who know about such things will explain that the 360 CPS has two (not three) wires and is a completely different shape and fitting to the 940 one…
… but it does have the right range of impedance and the end will physically fit in the bell-housing!
Not wanting to destroy an otherwise good part (with no guarantee of success), we chopped the connector off the faulty 360 sensor and searched for something to join the bare ends to the relevant two pins on the 940 item's connector. Unfortunately neither of us had brought an electrical connector/crimp kit, much less a soldering iron etc. BTW we were basically in a yard miles from nowhere; no shops around even if it hadn't been late afternoon / early evening on a Saturday.
We didn't have enough hands so my brother found some rawl plugs (yes the things that go into walls to screw stuff onto!) in my 'misc' toolbox and some monumental bodging ensued. The split ends of the rawl plugs were used to hold the bared wires, from the 360's CPS plug, to the correct pins, in the 940's CPS plug, while he held the sensor element in roughly the right position and I turned the car over. After a quick check that we were now seeing spark and fuel, we replaced everything we had been fiddling with and … she fired up.
We were already towing and there was no way that lash-up was going to make it the 100+ miles back so she isn't back on my driveway yet but at least the fault, and required solution, are confirmed.
Now I was warned CPS's can cost in the region of £200 which isn't far off what I paid for the car - which is why 'friend of a friend' wanted me to decide what to do - so I will be looking at cheapo options! Luckily my brother took one look at the 360's and called it a 'Renault type' so maybe I will get down the local scrappie's with my trusty multi-meter to find a good used one off something French
The down sides are I don't have any pictures (but chopped wiring is not that interesting!), we didn't get back until 00:45 and we may have destroyed my brother's Discovery's gearbox – off to look at it now but that's for another Forum!
Shoestring
... 
