75ZT Community

Hello all. I am devastated.. I have had to abandon my beloved v6 tourer 400 miles from home. Drove 400 miles to collect wheels for my mini and then further to collect other stuff. When i stopped, the engine was revving up at 2500rpm. Stopped it, collected the wheels and then it wouldnt restart. Checked for fuel pressure. ok. Local garage recovered it and checked codes. Cam sensor circuit, O2 sensors and Vis motors. I knew about o2 sensor one and have new ones arrived day before i left on my journey. Fitted cam sensor, no change. fitted crank sensor, no change. While searching for problems i found an unplugged or unused plug identical to the cam sensor one lying on top of the gearbox. Anybody any ideas?

maybe in tank pump separation & needs the orange clip, have you they checked the wiring from the exhaust 02 sensor the wire can chaff, on the heat shield which may stop the car from starting, it's cranking over i presume.

Thanks Artic. I checked the fuel pressure at the tank end and at the rail. Plenty pressure I would say. Also there is a label on the tank unit to say clip fitted (screw) and the date. I am thinking that wouldnt cause idling at 2500 but maybe the o2 sensor could?

You can ignore the Vis motor ones, they will not cause a failure to start. Ideally you need it on a T4 (Testbook version 4.Computer Diagnostic System) diagnostics to find the problem.
Here is a map of known T4 operators
https://www.google.com/maps/d/u/0/viewe ... 359583&z=6

I wonder if it the LPG (Liquified Petroleum Gas) system that is causing it, i remember Rob (trebor) had a similar problem with his car and it turned out to be a wire on the PLG system.

The revving and the failure to start may not be related.

The V6s can get a sticky throttle cable if it's really cold, though I would have thought it would be warm enough after 400 miles.

Fault code for Cam sensor though, could explain it. The cam sensors start to go faulty when hot, but be OK again when cooled down. There is another potential cause given the O2 sensor code. The cam sensor and O2 sensors share a fuse for their power feed. I've known of a case where the wiring to the rear O2 sensor had rubbed insulation, and when the engine moved on it's mounts it would short and blow the fuse. Then the car wouldn't start. New fuse and all was well, until the engine moved which it only did sufficiently when driving.

Plug on the gearbox top will be for the traction control sensor. I assume you don't have TC?

EDIT:
Just re-read the thread. Arctic is suggesting the same fault as I am. So check the relevant fuse. I see you have tried a replacement cam sensor already.

Brilliant guys.. thanks for the T4 map takestock.. nearest one about 110 miles! Handy to know. Car is still 400 miles away, the garage said they tried a new crank sensor but in fact they only broke the bolt! Duncan, either you or I clairvoyant. I got up this morning with the intention of asking if the cam sensor and o2 sensors share a feed! Artic had suggested chafed wiring and I realised that I had fitted a new front pipe/cat as the flexy had ripped. The replacement allowed the downstream sensor to sit unacceptably close to the shields. I 'adjusted' the shield as best i could. However, towing a Mini on a trailer on a bumpy Yorkshire backroad could allow more movement that usual. I think we may have hit the nail on the head! I dont suppose we can pass on the fuse location and number to the garage..? Would rather drive it home! And would rather it be seen (and heard|) driving home!

Fuse 3 15A in under bonnet fusebox.

thanks Duncan. will phone the garage tomorrow.