V6 breakdown symptoms

[Mrs Feynmans Bongos]

Yesterday gave my V6 her weekly run to work (20 miles) and back.. almost. She broke down 1.5 miles from home. Would appreciate expert thoughts on what may have happened, advice what to do next.

She has been running really well, sailed through MOT August (just needed an ABS sensor);

Leaked oil around head until a couple of years ago (MOT comments). "Blue Devil Oil Stop Leak" applied 2023 (when oil filter last replaced) seemed to have eliminated this;

With only ~3 litres of fuel left at work, I added 5 litres of E5 Super from my can (warning went OFF until halfway home). Filled up with E5 as planned 2 miles from home;

Left garage ok, 300m later held on roundabout by traffic lights. On exiting roundabout, engine cut out with ?usual Oil, Ignition warning lights, no strange noises or smells at all, was able to coast aside safely despite power steering loss;

Tried to restart a few times: she cranks and splutters but does not catch. Electrics otherwise seem ok (lights, dash, aircon, radio). No oil evident underneath or on road nearly, nothing looks wrong under bonnet, but I couldn't face raising seat cowls in the dark so walked home.

THOUGHTS PLEASE.

Oil starvation?
Misfuel? (Garage's fault, pump said £145.9 ppl E5!)
Fuse or relay blown? (which, as engine-type not cabin)
HT leads failed? (Had vermin trouble some years ago)
Spark plug failed? (replaced 10 years, 40k miles ago)
Fuel blockage? (unwise to run tank so low)
:

HELP APPRECIATED

[g8dhe]

Not really a lot to go on given that it just stopped, my first line would be distributor and HT coil areas. If it was an HT lead or a spark plug only one cylinder would be affected, for all cylinders to go would tend to point to HT generation and distribution, the fact that it had been running would suggest that there wasn't any moisture causing problems, so either the coil its connection to the distributor, king lead or the distributor itself.

[Mrs Feynmans Bongos]

Thanks Geoff.

Garage recalled the receipt for me: it shows SUPER UNLEADED, they have no recent misfuel reports from that pump.

COIL, DISTRIBUTOR, KING LEAD: any way an amateur like me without garage equipment (only a multimeter!) can rule those in or out, or is it just a case of replacing them in-turn? (maybe at side of road, if I can order them for Monday, given recovery will be a £200 trailer job!)

[g8dhe]

Well have you first tried looking at them that can sometimes offer a clue ?
Try cleaning the them up to remove all the road muck that gets sprayed up on them ?
Taking the distributor cap off and inspecting inside make sure you keep its exact position noted, the contacts inside and the rotor do have an odd looking rough surface to them which is correct - this sometimes confuses people if there not aware!
Diagrams of the various parts listed here under Ignition and Distributor https://www.lushprojects.com/bongoparts ... Btr.html#4