Try Rimmer Bros. Definitely go to gomog. There is a GEMS manual available there plus a lot of very useful info.
You rang, Sospan?
Heads up. I am about to add confusion,
I do not pretend to be a GEMS expert, preferring to focus on LR/Rover L-Jetronics (1984-1990) and LR/Hitachi Hotwires. eMog's anointed GEMS guru was the dear David Poole who wrote that brilliant
https://www.gomog.com/allmorgan/GEMS/GEMSbyPoole.pdf on GoMoG. I believe his was the first such on the planet and was downloaded by everyone with a V8 GEMS for years. Still is.
GEMS is/was an aftermarket firm with a lot of V8 variants, even within the Morgan world. The first was the earlier overseas GEMS Morgans (1996-2000), a period during which stock Plus 8s remained with the Hitachi Hotwire. These earliest GEMS, IIRC correctly, had a performant version mitigated by their MUCH heavier weight) with fuel maps overseen by Chris Lawrence. And the second overseas GEMS can be very different the first! David worked with that, though he is very knowledgeable on all versions. .
The point is that I find no reference in Poole's Manual for a Code 1147 though he speaks of evaporative emissions. AI (which we all now know very much is US-variant oriented
without explaining that) or google searches (same issue) lead to Land Rovers equipped with the GEMS (Generic Engine Management System) used in the 1994–1999 Discovery I, Defender, Range Rover P38)
after which LR switched to Bosch Motronics. Morgan never used any Motronics in any car AFAIK. These sources (AI and google) say GEMS LR Code 1147 refers to Bank 2 (passenger's side in the UK and driver's side in the US), the Downstream O2 Sensor Heater (Lambda) after the cat, as a Circuit Malfunction.
THAT issue is very common and merely means A. checking that sensor's wiring and, most likely changing the sensor (they are relatively inexpensive generic wear part). It merely means the lambda's heating feature is not functioning properly, preventing the sensor from reaching its operating temperature quickly enough.
Curious,Wightmog. Which code reading device were you using?
And Sospan, could please lead me to the Rimmer's GEMS Manual?
Lorne
