Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing 2014 plus 4 engine cutting out

Hi guys I am looking for some advice. My plus 4 nearly a year old with 3000 miles on the clock has never missed a beat until today. I was travelling down the motorway at 70 mph put my foot down in 5th gear to overtake and the engine cut out. I pulled over to the hard shoulder thinking the worst, turned off the ignition, turned it back on and it started with no trouble. Went on my way and 5 minutes later it cut out again in exactly the same circumstances. I stopped, ignition off and on and away we went. I then travelled another 10 miles with no more problems but did not put my foot down hard at 70 mph.
Any ideas?

thanks
Dave Wilson

Did the eng management light come on? If so you ought to have a fault logged that could be decoded for a clue...

Only the battery light was on when I stopped.
The engine warning light comes on when turning on the ignition but goes out as soon as the fuel pump is up to pressure.

Do you have a fly by wire throttle? as in no throttle cable? if so it sounds like the TPS (Throttle Position Sensor) could be a good place to start. Think of it like a Scalextrix throttle controller, if it looses signal at the pedal or the under bonnet end (on the throttle butterfly crosshaft) end then the car will not know where the throttle is. The worrying thing is they normally default to idle. The fact you could cycle the ignition switch is a good clue as that's how the system resets itself (listen to the whirrs and clicks when you switch on and off). I would have a good look at the connectors integrity and secureness as a start. Good luck with it.

Well more knowledgable TMers will be along in a minute, but I would have thought had it been sensor or similar related it would show via the light, so maybe more likely fuel related rather than electrical?
A very bizarre fault I had years ago with similar symptoms turned out to be a stray label inside the tank.. Every so often when fuel demand was high it got sucked up onto the supply pipe and the engine would cut out. You can imagine it took a good while to suss out.
Tricky these days when it's not so easy to fit trial bits..

The fuel pump relay would be high on my list. Cheap to substitute but get one with a diode.

The fly by wire throttle sounds logical because how often do push the pedal to the metal in a manual transmission. I will try a heavy foot in a lower gear to prove it.
Thanks for the advice everyone...much appreciated.

Dave w

As your car is still under warranty, I'd be booking it in to the dealer and let him sort it out. Could save a lot of delving around!

Here is another cut out related item which may be of use to someone one day.
Travelling at 4000 rpm in fifth the engine would cut out die back to 1400 rpm and then be fine until the same constant 4000rpm would be reached at which point it all happened again. It turned out to be the alternator which once replaced cured the problem. Apparently it caused a short. When I posted this on Go Mog ten years ago the first reply was directed at the alternator but no one believed it.

+1

In fact trying to fix it yourself may eventually lead to problems if you need to make a warranty claim.