Car cuts out when driving.

[Steveb50]

Have a problem with the Stag where every now and again the car cuts out. I think the pump stops working. Sometimes I can drive 5 miles, sometimes 20 miles. It always starts up about 10 minutes later and drives, at this point I head home. To me who is not technical person but practical it seems like petrol starvation. I have cleaned all contacts where wires go too. When it first happened it backfired and cutout so I replaced the coil. Seemed to drive OK for a couple of days, then cut out. Changed the petrol pump thinking that the issue was that (even though I only changed pump last year from the original to a electronic pump) once more seemed to be driving OK for a few days and then it cut out again. But as I say it does restart after about 5-10 min (everything fires up OK when trying to start but just seems lack of petrol). I am now at the point where if I take the car out its a worry it will cut out. ANY THOUGHTS?

[Wheelz]

Feed to the fuel pump is via the inertia switch, which might be causing the problem. Temporarily bypass it and see if that clears it.

[Steveb50]

Hi Chris. My car has never had a inertia switch.

[wilf]

When it cuts out, does the rev counter drop to zero before the engine has? If so it is an ignition problem, most likely on the low tension side.

First thing to do - ensure all earths are well made.

[Wheelz]

Hi Chris. My car has never had a inertia switch.

It did when it left the factory.

PS: It's a safety feature so you really need to get one fitted.

[dasadrew]

I'm sure there will be differing opinions, but I'd say that, if it's a fuel feed problem the engine won't "cut out", but will start to run lumpy, then very irregular and will finally die. If the pump stops, the car will run up to a kilometer or so before it really protests. (to attack another Stag problem wih float valves sticking, I've installed a switch and occasionally switch off the pump about 500-600metres from home and let it run the fuel level down. The car makes it home ok, then I flick the switch and the pump gives a rush of fuel which according to the various theories around will give the needle valves a bit of a jolt - so to speak)

[richardthestag]

It doesn't pain me at all to agree with you Wheelz , deal with that h8ters

Inertia switch is in place because in event of a severe accident fuel doesn't continue to pump.

Crazy to bypass or delete it, because you do not know when a drug fuelled cretin will choose to drive straight into you.

Else what Drew said, a dead cut! engine dies instantly and rev counter drops to zero is more likely to be ignition related.

If the car starts to drive more and more sluggish before failing then I would be looking at fuel.

However rule #1 when dealing with these issues; 99% of ignition symptom problems end up being fuel supply related and vice versa

[jbuckl]

Possibly coil is breaking down when hot?
Rev counter is a good tell tale for this, as others mentioned.

[singapore stag]

I had similar problems on two occasions when new to Stag ownership. The first time it happened I located the problem down to faulty Lumenition ignition.
Then the problem arose several years later. This time round the fault was the Inertia Switch.

[dasadrew]

Have a problem with the Stag where every now and again the car cuts out.....

As you might have seen from the posts so far, I think you need to give us a bit more information to help with the diagnosis. What is it that makes you think it's fuel starvation? If the symptoms are those described in the posts for fuel starvation, then a possible cause could be in the direction of fuel tank vent. It would explain why the car starts fine after 10 minutes. If air cannot enter the tank to replace used fuel, a partial vacuum will be created and the pump might find it hard to work against it. Pausing for 10 minutes would allow air to "seep" back in. You're now on your third fuel pump; did you change the pumps due to this cutting out? If so, it looks like you could eliminate fuel pump as a cause.

Try to define what you understand to be "cutting out" - loss of power? lumpy running until idle can't be maintained? Very sudden and sometimes intermittent loss of the engine?

Is the distributor with the original points, or electronic?

If someone has removed the inertia switch in the past, try to see what was done with the two wires which originally went to it; are they joined up in a reliable fashion? They should be in thearea where the inertia switch was on the bulkhead, wires should be white and white/green I think.

Drew

[Steveb50]

Thanks all for your thoughts. As mentioned in reply to one comment the coil was changed. Drew. In answer to your questions. I will take a look at the tank vents, are they on top or on side? 1st pump was the old original pump (points) that I changed last April to the new version due to the points sticking, which over come that problem. However problem I have now started 4 weeks ago so changed coil then pump again to see if that was the problem, but still the same. Car just cuts out, not lumpy or shudder. Just cuts out and stops. When I check pump it's not making noise. Since cutting out I have been driving with the pump exposed so I can check it when car stops. Distributer is electronic. I will check the wires where the inertia switch was. Just to clarify car drives OK then just ramdomly stops, no shuddering /or any other signs, just cuts out. After 5 - 10 mins car (after trying to start it) will start and seems to drive OK. I have been driving local to home so I head home and leave car on drive ticking over for about 10mins and all seems to run fine. Sometimes I can drive 20 miles and sometimes 5miles before it cuts out.

[dasadrew]

ignition switch? wiggle it when the car is running

[Steveb50]

Looked at inertia wiring, checked tank vent and wiggled ignition switch. All OK. Took car out, it cut out after about 6 miles. Started up as usual after about 10 min. Drove home and let car tick over for about 30mins on drive and revving every now and again. All was working OK. Did not cut out.
Turned car off. Not sure what's happening!!!!!!

[dasadrew]

have you got an electronic ignition?

[NeilR]

It may well be another powespark/accuspark.
I had two of those type issues, fine when cold, fault became apparent when hot.