V6 breakdown symptoms

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Mrs Feynmans Bongos
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V6 breakdown symptoms

Post by Mrs Feynmans Bongos » Sat Nov 01, 2025 9:47 am

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 😄
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g8dhe
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Re: V6 breakdown symptoms

Post by g8dhe » Sat Nov 01, 2025 9:57 am

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.
Geoff
2001 Aero V6, AFT, full side conversion.
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Mrs Feynmans Bongos
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Re: V6 breakdown symptoms

Post by Mrs Feynmans Bongos » Sat Nov 01, 2025 11:36 am

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!)
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Re: V6 breakdown symptoms

Post by g8dhe » Sat Nov 01, 2025 12:03 pm

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
Geoff
2001 Aero V6, AFT, full side conversion.
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Re: V6 breakdown symptoms

Post by Doone » Sun Nov 02, 2025 9:10 am

Theres no common problem why a V6 suddenly cuts out, they do it so rarely.
As it happened after you'd run low on fuel, you could check the fuel filter.
Dirt can block the filter enough to cause fuel starvation.
Especially if it hasn't been replaced recently.
Allans Garage retired. Try PGS (Plymouth Garage Services) or Mayflower Auto Services Plymouth
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Mrs Feynmans Bongos
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Re: V6 breakdown symptoms

Post by Mrs Feynmans Bongos » Sun Nov 02, 2025 7:08 pm

I tried a few things today, given she's less than 2 miles from home. Mild and sunny so could have been worse..

Found NOTHING on the dipstick, worryingly (even if stranded on a slight slope) After adding 3.5 litres of 5W30 she now shows FULL on the stick when cold:: but is this too much? Clearly I need to check oil more often..

That made me wonder whether oil starvation is detected, whereupon oil warning lights-up which cuts ignition? (the opposite of my assumption about Friday breakdown: namely ignition/engine stopped, causing an incidental warning light as oil pressure fell).

So then I replaced HT leads: removing ones I fitted 10 years ago, which are showing recent vermin damage to rubber boots and cable insulation (also some nuts on the cylinder head!). Reconnected to in situ DISTRIBUTOR assuming:
- dizzy sockets are correctly shown on:
https://bongospares.co.uk/shop/p/distributor-cap-v6-new
- those sockets should go to plugs/cylinders as numbered in
viewtopic.php?t=68624#p648223, presumably numbered from FRONT of Bongo?

Whereupon she cranks and sounds like she wants to start even more than on Friday and Saturday! On locking up, I also left my solar charger plugged in on the dashboard.

So it looks like the DIZZY next, then maybe SPARK PLUGS,
both fitted by me 10 years, 40k miles ago. Could they be end of life? What about the COIL: still original one, 100k miles.

Thanks for replying Allan (great to see you still on here even while retired: we can't spare you you know!) Not sure if I can check/replace FUEL FILTER from cabin via the cowls though? I am trying NOT to need to get it recovered!
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Re: V6 breakdown symptoms

Post by g8dhe » Sun Nov 02, 2025 7:24 pm

The dashboard light is merely an Oil Pressure light to indicate that there is a problem, it controls nothing else other than the light;
Screenshot 2025-11-02 181843.jpg
However its worrying that you could fit 3.5l of oil in that would tend to indicate that you had lost a lot as the total is 4.5l in the specifications!
Geoff
2001 Aero V6, AFT, full side conversion.
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Re: V6 breakdown symptoms

Post by Mrs Feynmans Bongos » Mon Nov 03, 2025 8:11 am

Ah thanks Geoff. Sounds much more likely the Oil warning is just the effect of the engine cut-out then, not the cause.

As Allan suggested, I am actually thinking now a FUEL BLOCKAGE best fits the facts as investigated. It died immediately after fuelling from very low, HT leads ruled out, unlikely Dizzy +Rotor (although I have ordered new ones) given it "wants to start" anyway these are only "40k miles" and it has been running well.

Can I replace Fuel filter from above/cabin via engine cowls? Is this designed to "block" rather than fuel pipes? Or more advisable to bite the bullet and recover it to a garage now, as fuel blockage is quite an expert job?
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Re: V6 breakdown symptoms

Post by Doone » Mon Nov 03, 2025 8:59 am

The numbers on that link are correct.
The cap will only fit one way.

The fuel filter is under the van, at the front of the fuel tank. It's a black canister on the chassis. Its held on with a bolt through the bracket & 2x 10ml nuts. When you disconnect the pipe, fuel might spray out.

Trouble is, we're just guessing and the fuel thing may not be the problem as your electrics sound pretty old and may be worn out. They're pretty crucial on the V6. And it sounds like its improved a bit by changing the plug leads.

I'd check the coil lead. It runs from the coil to the distributor cap. You can check the ohms with a multimeter. The correct readings will be on the forum somewhere I expect.

And check the rotor arm, its inside the distributor cap. If its covered in scorch marks or is corroded, change it.

As you've lost so much oil, it suggests you've had a leak. The oil could be on the TDC sensor, giving a bad signal. This would also cause starting problems.
Allans Garage retired. Try PGS (Plymouth Garage Services) or Mayflower Auto Services Plymouth
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