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MG MGF Technical - Not starting, update!!!

Right the story so far............

I've finally manage to get a spark from each of the plugs after drying off and spraying the coils with WD40. The car still won't start but I'm guessing this is because it is flooded. I've tried to find the fuse for the fuel pump so that I can turn it over without pumping fuel but every fuse I find on the wiring diagram is also linked to the ECU so if I pull it it wont even turn over. Anybody know exactly which fuse I should pull?

Also does anybody know which is the fuse pump relay, as I could pull it out and try starting it that way to get rid of my flooded engine.

Just like to say thanks for all those people who have helped so far.



Have you checked the fuel cutoff switch in the boot/engine,just wondering if its jumped to the off postion.
Joe one

No problem with fuel getting there as I think the engine is flooded.

Suppose I could swith the fuel cut off switch to off to try and burn up some of the fuel. Do you know where it is?


under the bonnet fuse 2
Will Munns

the inertia switch is tucked up on the LHS above the innner wing (IIRC) it has a big rubber button to reset, the only way to stun it into action is to give it some sharp taps with the base of a screwdriver
Will Munns

Thanks but which is fuse two as they are not numbered. Also does this not affect the ECU as well which means no turning over?


Is there any ohter way of starting a flooded engine?

The numbering is on the inside of the lid, this fuse only goes to the fuel pump.

And a very good spark _may_ ignite in a flooded engine, so connecting to a running car with jump leads may help.

Usually you could just leave the petrol to evaporate and find it's own way out, but in this weather that will take a bloody long time (in days)
Will Munns

Thanks for all the help Will. Thought I'd looked at the lid for the numbers but must have missed them. Will go give it a try now.

Thanks again,


Will, there's no numbers on the lid. It just tells you what the ratings are. Any idea which number 2 is?


Think I might have it by looking at the wiring diagram. Theres only a couple of 30a fuses and one of them is the one I'm after!!

numbered from the bottom by the look of it
Will Munns

scrub that, the fuse is used for other stuff
Will Munns

just gone to look at my car and the inetia switch is dead easy to find, look thru the grill, the only black thing (almost the only thing) on the far left wall of the engine bay is the inertia switch., push the button to see what it feels like, then give it a few swift taps, it should now feel diffrent thru the rubber, but this act will have reset it, so try again, if it feels the same then try harder
Will Munns

Yet another update.

Found the fuel cut of switch and turned over then engine with no fuel going to it. Reset the switch and tried to fire it joy. Still just turning over but not firing. Took all the plugs out and checked I as getting a spark on each. All plugs are sparking nicely.

Left the plugs out to see if it helps in evaportaing some of the fuel off from the block. Plugs looked pretty wet with fuel when I took them out so still hoping it's just a flooded engine.

Would anything else stop it from firing up (air flow sensor or something like that), like I've said I'm getting fuel and a spark but still no go!!!!



engine immobiliser om?
Derrick Rowe

fuel pump not working?

No petrol in tank?
Derrick Rowe

Did you try really heating the plugs over a gas hob or with a blow torch.

Are you sure nothing else has changed David - it used to start fine, then it snowed now it doesn't?

Where did the snow lie/melt? How could it get to the plug leads?

I expect your battery charger is working overtime as it will be taking a beating during this little exercise ;-)

John Thomas

Derrick, if the immobiliser is not working would'nt it fail to turn over? Fuel pump working fine and plenty in the tank, thinking too much fuel is the problem!!!

John, yea the charger is earning it's keep this week!!! Snow near enough covered the engine (lots of snow and very windy blowing it straight in there).




If you have sparks and looks like fuel on the plugs so presumably its firing at the correct piston position (ie timeing is right) and anyhow how would timing go off with snow !! Its just leaves
a) Enough air in
b) no blockage in the exaust.

Obviously if no air in then can't ignite and if exaust is blocked it can't breathe.

I assume no snow in exausts as wold have melted by now.

air filter not blocked ? or throttle not working correctly ?

You could let it try a dry out incase of flooding, and heat the spark plugs.

Next there is Damp Start !

Not sure I I should recommend this or not as apparently its not great with engines and I have neverused it on my F but on other cars.

A squirt of this and as its so flamable it will usually start any engine. you could try this as last resort if sure throttle ok and air in ok and no exaust blockage.


Damp start will start engines with no petrol and no spark, they don't stay started for long!

On the only occasion that I had the F fail to start I dried everything out using a hairdryer, but I was able to do this in a garage - car restarted after about one hour of drying.

How long did you crank with the fuel pump off?
Are you sure the fuel pump was actually off?
Will Munns

Brian, yea there is no snow in the exhaust and the filter looks fine. Not sure about the throttle, how do I test it?

Will, cranked it with the fuel pump off for a couple of mins. Sure it was off as I took out one of the plugs and there was no spray of petrol (turning it over with fuel pump on and plug out results in fine spray of petrol coming out of the plug hole).

Going away this weekend so not going to try and start it till Monday and see if that makes any difference.

Just glad the wife is selling it this year as it's been nothing but trouble:

HGF twice
Air con pump siezed (not cheap!!!)
Altenator replaced
Leaks in everywhere (although it's better now I've adjusted the windows)
Any you never know if it's going to start or not.

There is more but I'm depressing myself on how much we have spent keeping it running......bahhhhh


Have you tried the good old way of bump starting it, either down hill or towing it behind another car, always worked for me in the old days.
jim kenny

I'd be careful about bump starting it as it could damage the catalitic convertor.

Ensure the plug gaps are set at their minimum. They may well fire in open air but under compression can be a different story.

Bruce Caldwell

When you checked your plugs to see if you had a spark did you notice if the plugs were wet or not? If not they should be if you have been trying to start!

Colin, the plugs were wet with petrol so I assume the petrol delivery is OK.

Was going to have another go today but it's pouring down!!!

Whats the correct plug gap for a VVCi?

Will try to dry the engine out and heat the plugs with a blow torch to see if that helps.



This thread was discussed between 22/03/2006 and 27/03/2006

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