engine randomly cutting out (and backfire)

[Mark Shutt]

got an intermittent problem with the running of my Stag, it's happened twice now and it's a bit of a concern engine cuts out randomly with no fore warning ie- no spluttering just stops like key out of ignition! it did it today whilst doing about 50, just instantly died for a few seconds, then there was a backfire pop and it carried on

any ideas? is this likely to be a fuel issue or ignition? my hunch is towards ignition.. Luminition by the way!

[Dave M]

I would check the engine cut off switch, grey tube located under the bonnet on the bulkhead on the passenger side. It's designed to shut off the fuel pump/ignition (not sure if it's both) should the car roll. The contacts get corroded and can cause the issue your getting, think it's a ball sat on some contacts, it's easy enough to temporarily short out to test if that cures your problem

[Mark Shutt]

I would check the engine cut off switch, grey tube located under the bonnet on the bulkhead on the passenger side. It's designed to shut off the fuel pump/ignition (not sure if it's both) should the car roll. The contacts get corroded and can cause the issue your getting, think it's a ball sat on some contacts, it's easy enough to temporarily short out to test if that cures your problem

thanks Dave, will make a temporary jump wire to bypass it and check switch.. I renewed most of the wiring on the bulkhead when I did the top end rebuild so connections should be OK but never say never!

[Mark Shutt]

just took switch apart and cleaned the brass collar, there was some corrosion causing an intermittent connection, not 100% convinced this is my problem but it can be ruled out now! it didn't feel like a fuel issue but only time will tell!

[V Mad]

Mark, where is your Lumenition power (RED wire) connected to? That power feed might be cutting out. The correct place is the white wire circuit - Ignition Control. Note: it is often connected to the COIL+ which is incorrect on a ballasted system like the stag.

Also check if the power feed to the coil is reliable: a bad ballast connection in the loom could be the culprit.

[Mark Shutt]

thanks Chris, red power feed for Luminition goes inside car to main board under passenger side dash.. when I did the loom I never got as far up the loom to find the ballast wire! but replaced all hard dried up cables.

[nigele]

Also check the red plug and socket between the Lumenition and the distributor. Mine cut out a few times, the rev counter dropped instantly to zero so I was pretty sure it was ignition related. I cleaned and tightened the contacts in the Lumenition plug and it's been fine since.

Nigel

[Mark Shutt]

Also check the red plug and socket between the Lumenition and the distributor. Mine cut out a few times, the rev counter dropped instantly to zero so I was pretty sure it was ignition related. I cleaned and tightened the contacts in the Lumenition plug and it's been fine since.

Nigel

yes, mine did exactly that, rev counter dropped, more avenues to check over, thanks that 3way plug is very fiddly though..

[72BLUE]

Mark, I replaced my red plug/socket with one of these waterproof connectors:

http://www.ebay.co.uk/itm/140938481535?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Been good so far............


Cheers
Keith

[Mark Shutt]

thanks keith, I think it could be the 3way connector, just had a look and the earth one (black wire) terminal was quite enlarged so squeezed it tight again and took it for a blast and so far OK

will get one ordered!

[Mark Shutt]

..oh, something else I noticed and thought was not right but not sure, I have 12v+ at coil with ignition on, I was expecting 6v+

[V Mad]

..oh, something else I noticed and thought was not right but not sure, I have 12v+ at coil with ignition on, I was expecting 6v+

Mark, the volts go up and down between 6v and 12v as engine turns. To check just short the COIL NEG to chassis, then it should read about 6V (dont leave the short there for too long though).

[DJT]

Mark, I replaced my red plug/socket with one of these waterproof connectors:

http://www.ebay.co.uk/itm/140938481535?_trksid=p2060353.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Been good so far............


Cheers
Keith

+1

[KOY 23]

Good move Keith.

[Mark Shutt]

today the part came so fitted it, what a PITA to fit/solder in place behind distributor! very fiddly at best but managed to get them securely soldered and crimped abd the job turned out OK

thanks for the link/tip off of this connection!

Mark.