Technical Very unusual non-starting problem on 55s

[dannyboy485]

Hi guys,
Its been a while since ive been on here.Ive got another 55s as a run-around due to the valve stem seals going on last one.

My 'new' 1996 55 has recently stopped working.
This is the story-
I bought a second hand 55 that had no keys for next to nothing (had very low mileage)so i transfered locks,ecu,code box all to new car from older one as its getting scrapped.I drove it back without a problem and started fine everyday no problem.
One day i started the car up for 5 minutes letting engine heat up so i could have a nice warm car to drive-then all of a sudden it cut-out.Didnt splutter,just cut straight out like someone turned it off.Turned engine off,checked the fuel guage(had put 10 l of pertol in before so not out of fuel)
Noticed the Key code light was on and the injector light was off-i thought maybe immo problem.put red key in,cranked but no start.

Now it gets interesting.The double relay was clicking completely randomly.Sometimes very fast,sometimes slow,then one or two bursts or random amount.I took the airfilter cover off and noticed the injector was randomly priming with relay clicks(pump was running on and off).
Also the injector light on the dash come on randomly for split second then off.like it accepts the code ,then doesnt.this is on the ON postion(not cranking)

so i unplugged the immo box on both connectors so the code light goes out but the relay still does it unusuall clicking so the code box and RF ring has been ruled out.

Ive checked most of the wiring no real problem anywhere.
help guys, Must be the ecu,what do you think guys? Its 16f one

 

[fingers99]

Very odd. I'd think it unlikely to be the ECU. Wing twixt code box and ECU? Bad earth (usual cause of clicking).

 

[dannyboy485]

Ive ohms tested most of the earths on the car and theyre fine. I used to have a wiring diagram for the 55 but cant find it. i did check. because it happened very sudden i was thinking maybe ecu but as you said maybe im missing something. Deffo not the code or ring because it does it even when theyre dissconnected so its engine bay/eath fault

 

[fingers99]

I find meters useful in tracking permanent faults. For intermittent, nothing beats the undo it, clean it, smear it with silicone grease and tighten it well up method.