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MG MGF Technical - Engine light flashes (after Gearbox change)


After I had my gearbox changed (BRM box,clutch, flywheel) the Engine light flashes for a few seconds is ok for 10 minutes then flashes again.

Has anybody a clue why this could happen _after_ a gearbox change ? (faulty Lambda?) What could it mean ?

Can I drive safely to the workshop ?


Regards,
Thierry
Thierry Zoller

Hi Thierry,
probably something simple as a jammed or poorly connected cable. Take it back to where the box was installed and let them sort it out. This light is there for envioremental (sp?) reasons,so if it clearly is the Engine light you should be able to drive to the dealer. Althou possibly at reduced performance ;O) / Carl.
Carl Blom

Thanks carl. The engine light is also obd2 compliant, which means that it displays various faults by not blinking but remain steady on.


Thierry

EU2 compliant engines don't have a MIL Thierrry - which engine light is coming on on your Trophy? Otherwise, I'd agree with Carl's thoughts on this.
Rob Bell

This is wrong, it's an obd2 requirement to have an engine status light. Note I say "ODB2" not EU2. I have seen them in all post 2000 cars, a toyota and a daewo.

Been to the workshop, well they couldn't find anything, 7 intermittant faults (misfire, connection lost etc). Reset them all cleaned the plugs. On the way home same problems appear. Testbook gives OK for all sensors.

I have another appointement on monday, anything I should keep an eye on or maybe I can do myself ?






Thierry

OBD2 is a USA on board diagnostics electronic standard. The European equivalent is EU3 that became fully enforced in 2001. Some confusion arises because EU3 mandated the use of an OBD2-style ECU diagnostics standard (hence the OBD port on EU3 MGs)...

Anyway - d'oh! - I forgot that yours was a fully homologated Trophy160 - and hence EU3.

I wonder what is giving your intermittent misfire fault?
Rob Bell

The misfire could be due a lot of things, sometimes this happens when you start too early and the engine dies. It ain't related to that issue, the car drives like a charm. (Especialy with the rover 200 BRM box).

What about that WIKI for your site ?
Thierry Zoller

The engine light activity could be un-related to anything detected by the ECU. It means only that the light has power and earth.
Your car may well have an electrical problem that is causing an occasional misfire and lighting this lamp - it could be a bent/damaged pin in a connector, or damaged wiring.
If conventional diagnostics reveal nothing, then I'd investigate other causes for the lamp lighting.

I had one case (on a different car) where the oil light would come on with bright sunshine coming through a gap in the console !
Steve

Thierry, how about the sensor/pickup related to the flywheel tdc position.

I can't think of it's proper name or location, but the F must have one somewhere and it's the one quite likely to be disturbed by a gearbox removal/refitting.

Look for dodgy connections or fixings?

jt
John Thomas

Thierry, the Wiki looked really good - and as you say, perfect for an MGF FAQ. :o)

Good to hear that the car is running really well Thierry - what ratios does the BRM gearbox use? Do you also have the Torsen LSD? :o)
Rob Bell

@Steve.
As far as I know the light flickers at a specific interval, if it only had power and earth it would stay on, like it does when other faults occur.

@John
I don't think there is one! Not sure though. Cylinder 1+4 need to be at tdc then the flywheel slips in nicely (according to steve @vibrationfree)

@Rob
Yes Torsen lsd! Standart Rover BRM gearbox, longer first, shorter fifth.
Thierry

Thierry, the thing I was talking about was the crank angle sensor.
This is what it looks like on a k series caterham
http://homepage.swissonline.ch/TomsSeven/What%20is%20it/CAS_wit.htm

Must be something similar on the F, and quite possible to disturb it when g/box is removed.

I'd have thought the garage diagnostics might have spotted if it was dodgy - but you never know.

jt
John Thomas

Engine Light? Which one?
I get the engine bay overheat warning light come on momentarily when doing high 'g' left hand turns. Dealer could't work it out, I assume its just a minor short circuit as the wiring moves. If you had the gearbox done, you could possibly suspect some minor damage to the wiring when they were messing about down in there. Other family MGF just came back from the garage with a severely bent gear change link...These things happen!
rhoops

Thanks John,Steve, Rob, it appears to have been the CAS sensor, it wasn't faulty, it wasn't snychronised to the new flywheel, the cas sensor registered temporary fluctuations of about 6000rpm in measurements (apparently) They reset mems to learn the new variables and "synchronised the flywheel" (quote).

The error hasn't come back yet so I suppose it was linked to it.
Thierry

Nice one, good result Thierry :o)
Rob Bell

bullseye :-)
John Thomas

This thread was discussed between 21/01/2005 and 03/02/2005

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