MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGF Technical - MGF: Sudden Death

Urgent expert advice needed. I was driving my F -20ks only- when suddenly the engine went off -check-engine light flashed for a moment-. I tried and the engine started again. A few engine failures followed but I managed to drive near home until she finally gave up and had to call AAA. Everything is apparently well. Temp, oil, and all other indicators are correct. Now the engine is running again, iddling but often stops.
Saturday to make things worse!. I will appreciate every expert suggestion about possible failures (fuel pump perhaps?)
JM Vega-P.

Hi Michael,

most common is fuel pump. Reffer to Tony's site and advise to 'hear' whether it's running after ignition on, or not.

Other could be cables to the Main Relais or Main Relais itself.

And of course ignition cables, distributor at MPI. Is it a VVC ?
Dieter K.

*g, ignition coil .. damn I forgot to mention this known trouble.
More often happening at the VVC, but MPI sometimes failed as well.
Dieter K.

Cheers Dieter and many thanks indeed.
My F is a regular 97 MPI, but quite new, running the last two years only.
The actual facts are most strange as I start the car successfully and left it idling but a few minutes later it stops. So it is an intermittent but frequent failure. Any suggestion? -as how to follow a procedure list to rule out problems?-.
Best .... Mike
JM Vega-P.

Strange...

Assuming it's no ignition problem.
Then fuel or air is missing ? I don't know.

Air ..
... controlled by idle air temp valve (stepper motor)
- can be left out, IMO, cause your engine at first died while driving, is it ?

... hmm, is the air inlet hose and/or airfilter blocked by anything ?

I hope it's not a broken catalyst. This would block air outlet though.

Sensors...
no idea currently but the oxygen sensor, may be.

Fuel...
does the fuel pump work or not ?

Easy check (not precise though).
Please check whether the brown-pink (BP) wire i.e. at the purge valve has +power just after the engine goes dead. This is a wire of the main relais, powerded by MEMS ECU. Easy to reach and you can DIY with a simple test lamp. (stitch test-lamp needle through wire isolation)
http://www.mgfcar.de/schedules/sb7.jpg

Does the fuel pressure valve (mechanical only) work or not. *no idea how to check*

Back to ignition.
Do you have wet ambient wheather conditions currently ?

If so, then I would suggest changing the distributor cap and finger.
Another one is the ignition coil, but I never heard of an intermittant failure with it.

Not much help though.

Dieter

Dieter K.

I had a similar problem and it was a loose connection in the plug that carries inputs and outputs to the ECU on the LH side of the engine bay mounted on the rearmost firewall. I found that by wriggling the whole plug I could stop the engine. Eventually traced it to a poor connection on the power IN line. I squeezed the female connector in the plug a little tighter before pushing the plug into the ECU and have had no problem since. Needless to say it initially occurred just as I was belting up to go racing. The stress sensor in the car was obviously working very well! I now carry a copy of the wiring to the ECU in the race kit of bits and pieces as insurance against such a thing ever happening again. Good luck with it Jim.

Regards and Best wishes for the Festive Season

David M
d mottram

Thank you very much guys. Dieter, we are in summer around here, sunny, 35°C and absolutely dry. I had the engine running in my garage last night. It run successfully for about an hour and then stopped. Many tries and could start it again. Looks to me as it may be a failure that is prone to appear when the oil temp reachs 90° or the engine bay is hot (?).
David, I dismantled the ECU and fiddled around the cables but really don´t know anything about.
A question mates: Do you know if the scanner failure codes for the F are available somewhere?. Or if the scanner cartridge for the F is similar to any other Rover engine?
Thank you lots... Mike.
JM Vega-P.

>we are in summer around here, sunny, 35°C and absolutely dry.

How boring ;), No snow storms ? No constant ongoing *country rain showers * ? And so hot ! Err, just seen, we are 8°C in HEF.

@ David,
I had nearly the same with my car recently. The Input connector fo the main relais has loose and additional the loom to the connector of the ECU was to tough pulled downwards due to a loose cable strip.

I put the wiring (mpi pre MY200) here
http://www.mgfcar.de/mems1.9/mems1.9.htm

The trouble I had is shown with some pics here
http://www.mgfcar.de/defects/start.htm

@ Mike,
So the engine cuts out after app 1 hour..... 90° Oil temp....
Hmm, not sure, I think this could be related to the coolant temp sensor and switch signal to the front coolant fan ?
Don't ask me about failure relation, but it's and option.

Anyway, you can verify.
Do you recall whether the front fan came off while the engine ran ??
Should have come off after a 30 minutes IMO under your current ambient temperature.

I measured the voltage it provides while getting warm.
The brown coloured sensor controls the ignition timing and the front fan relay. Fan comes off @ app 0.45 Volt.
at about 60°C mine had 0.59 V.

However, even if you could measure. The only I know is, that the fan runs always if the sensor is _disconnected_. (Rob tested)
This should be checked at first.
So what does the fan ?
- when engine cold
- after warming up to 90°

Best
Dieter
PS. I'm afraid, this analysis can last weeks. Isn't here any chance to go for a Testbook session ?



Dieter K.

Sorry about the weather Dieter. We already had our share of snowstorms last winter.
I will follow your suggestions and check the fan.
Agree that a scanner session is in order but I´ll have to wait until festive season is over :-(.
All good wishes and big thanks.... Mike
JM Vega-P.

Just to keep you all posted, Chaps. I know this is a tough case. I again started the F and had the engine iddling for about 90 minutes in the garden and finally it went off. Before I had check every connection to the ECU-MEMS and also the radiator fan which engages intermittently -at least one of them-, so I believe that might not be the problem. So I will have to wait until holidays are over. However I can not avoid begin to worry about how reliable this lovely car might be on a long trip. Best....Mike
JM Vega-P.

I was following the thread with interest as something similar striked my car short ago. The car was towed to a garage -not Rover- and they immediately decided to check some "oxygen sensor" as they said is the most common cause for this engine stops. Not very accurate but hope this help. Pierre
Pierre Arnaud

Just a thought

Oliver had a problem with his engine cutting out and refusing to start on the Riveria trip last year..

It was actually the fuel pump plugin connector ..one of the pins was slightly corroded and burnt... It easy to check as the fuel pump can be accessed from the round cover plate on the left side of the car next to the engine bay access plate..

Its worth checking this out.. could be a cheap fix !

Stu
Stu Dickens

Thank you Stu. I have already checked and found the petrol pump connector impecable. Cleaned it anyway.
At present the car starts quite normally and I left it idling in the garden every day -fear to drive away and be stalled again-. Eventually in a hour or so the engine stops but when trying starts again (????).
JM Vega-P.

btw, another idea. Can be totally mad, I din't know.
What about the fuel tank and attached purge valve ?

Mate, could you once let the fuel filler cap remain opened (removed) and repeat a test ?

When did you change the fuel filter for the last time ?

Dieter
PS. please correct me someone if this leads in wrong direction.
Dieter K.

Ooops, I better correct myself.
Just looked up the manual. Forget the purge valve please.

Dirty fuel filter is another story.
Dieter K.

Dieter, I have not changed fuel filter yet as the car, notwithstanding a 97 model, has 20.000 k only. Should I change it anyway?
JM Vega-P.

This thread was discussed between 27/12/2003 and 03/01/2004

MG MGF Technical index

This thread is from the archive. The Live MG MGF Technical BBS is active now.