Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Mass Airflow Sensor failure

I recently had the Mass Airflow Sensor fail on my 2003 Plus 8 w/ 4.0 liter engine. Of course it happened in the mountains of California with a long tow involved. The car was not drivable for any distance.

My question is; do these fail frequently? The car only has 5000 miles on it (the first owner didn't drive it much). If this is a common failure, I will purchase a spare.

Thanks,
Dave

Its a Morgan,they all do that,sir.

Hummers do it too!!

MAF sensor failures are pretty common on all cars according to an AA guy I was talking to, especially those that aren't driven much. The sensor wire is quite fragile and prone to dirt contamination. On GEMS Plus 8s the plug for the sensor is also right under the bonnet seam and can get damp and dirt working in there so the connection gives faulty readings to the ECU.

You can get spray cans of MAF sensor cleaner which maybe able to help, but the answer, as with everything car related, is to use the car frequently and replace air filters with good quality OEM.

I reckon it's well worth replacing any MAF sensor every 50k miles/10 years or so, and to buy decent quality, in the UK you can get OEM sensors for around £90 so it's not really worth buying cheap knock-offs

MAF sensors tend to get dirty through recirculated vapours passed into the air flow path.

I too have had a AMS fail on my Hotwire +8 , this was put down to vibration as one of the rubber mounts had disintegrated (as it is right underneath the housing it was missed , shows the value of making a thorough inspection every year or so even in the most inaccessible places on the car)

Although generic AMS are available at reasonable prices, these Rover units are now becoming quite rare and prices are not cheap. I tend to look out for them where I see Range Rover, Discos and other Rover V8 engined vehicles being dismantled.

But if you can't find one there is an alternative, you can ditch the SAGEM system altogether and go to one of these set ups, not cheap ~BUT probably better.

http://www.lloydspecialistdevelopments.co.uk/engine-management-kits

Dave,
There is a SUV wrecking yard near Seattle with several 4.0 Rovers in them. I might be able to source a spare for You. But I wonder if it is worth it as they are used. I have a complete 4.0 engine/Gems Injection that I bought for about $400 US. Not sure if I will ever use it, as I like My Edelbrock Carb system. As I doubt I will use this FI I suppose I could give you the AMS for an emergency spare and if I decided to use the FI ask for it back (doubtful).

Hi Bill,
Thanks for the offer. Right now I'm just trying to find out if this is a common issue. So far it doesn't sound like the GEMS system is any more failure prone than others. My car sat for 10 years, so this may have something to do with it. I'll let you know if I decide to take you up on your offer. The MAF is large enough that carrying a spare takes up some space and probably won't fit in my tool kit.

Overall, I am happy with the GEMS system, other than this issue, and the occasional EMS/Immobilizer failure to communicate, which I think I have resolved. I can understand liking the carb setup, easily repairable on the road.

We were headed from Sutter Creek back over to Minden the day after FlogMog and the MAF failed at about the most remote place possible. No cell service and miles from anywhere. We limped over the hill in first gear to Kirkwood, where we got cell service and called a tow truck. Since it was late Friday afternoon, the shop in Reno couldn't get to it until Monday and then a day waiting for a new MAF. We were able to stay at Donna's sister's home so the only real issue was the LARGE tow bill. I take it you made it back to Idaho and then Seattle with no problems. -Dave