Talk Morgan Forums Morgan Sports Cars Morgan Aero 8, 2012< Plus 8, SuperSports, Coupe & Aeromax Stalling when hot

I’ve hit a problem that only seems to appear when the car has been running for some time then gets into traffic. I had noticed a few times a weird situation when I left the car to warm up on the driveway and it reached temp that the revs dropped dramatically and sometimes the car caught it and revved back up and carried on but other times it stalled. I put that down to they all do that sir and forgot about it.

I’ve now noticed however that after a long run when I get into traffic the car stalls but then restarts on the button I then heel and toe it to prevent any other occurrences. I intend to get the car booked in to get the doors rehung and was going to ask if they could look at it but thought I’d ask if anyone else had come across this to give them a starter for 10 and hopefully save on the scratching head hours if possible!

I did see another post by Grumpy2 on the maintenance forum and asked there but I had a doh moment as his thread wasn’t for the BMW engine plus 8 so don’t think it will be the same issue.

Engine temperature on my Plus 8 seems to be controlled by both the thermostat and the fan, triggered by the overall engine temperature. It doesn't seem linked to engine revs other than in the winter when the engine revs at 1000 rpm until it is up to about 50C. In the winter the thermostat seems to stay shut until the engine is at about 110C, then the engine temperature drops rapidly to 80C and the cycle starts again. The fan is often running in summer, rarely in winter. I used to worry aboutt this variation, but in the 8 years I've owned the car it has remained the same.

If the engine revs are dropping to the point that it stalls then something is wrong and it needs looking at by a competent technician.

Quite possibly the MAF (Mass Air Flow) sensor.

I’ve had this a few times.

A friend of mine has just had this too the past weekend.

Acts in different ways but I’d start there

Cheers will let them know about that Viper.

Easy to pull off Kevin just remove the front cowl give it a spray with with a mass cleaner and try before assembling the cowl gone through three in 16yrs ownership. If you need to replace I found the pattern ones just as good. The air filter is Low on the series1 also check the air tube it sits very close to the tyre it may touch at full lock. I had a small wear hole in mine and sucked debris onto the mass sensor.

I might buy one as a spare to carry.

Where do you get yours?

Viper. The last one was off the internet Its the same as rhe v8 x5 petrol about 60 quid from memory. As an aside when I investigated my first issue I noticed the previous owner had changed to a K and n there was a trace of oil inside the maff on the mesh, never been a fan of k and n and replaced with a standard air filter also the big air pipe near the wheel was also cleaned it was the ribbed type I found it had grit lodged in the ribs I changed it to a smooth pipe much more substantial. As we all know a huge amount of heat is generated in that very cramped space with no real air circulation and every now and then it throws out a gremlin. The joys of series1 ownership but hey what a car......

Hope it is that as seems a cheap fix for once!🤞

not used this myself but I saved it from a while back when Em. / Aerotaff ( I think !) posted the info. -

MAF sensor 0280717814 Bosch 1433567

BMW X5 E53 4.4l Petrol Mass Air Flow Sensor Meter Bosch 1433567 0280217814

BMW 5(E39) 540i 7(E38) 740i,iL Mass Air Flow meter

- hope you get it sorted Kevin .....

James

Well done James, switched on or what. Hope the twin is behaving herself and your getting out and about.....Em