Mk 3 Refuses to start

07 2L wont start. My super reliable Mark 3 refuses to start this morning. Battery is fine - engine turns over as usual but no firing at all. Plugged in OBD11 but says no codes`
Plenty of fuel in the tank.
Any ideas please as to where to start?

As always you have to start with the basics. Is it getting fuel and is it getting spark?

Pop out the front plug after an attempt to start. If you are getting fuel the plug with smell of fresh petrol and may even be a little damp. If it does not then you have a fuel problem.

If you are getting fuel then reattach the coil to the car and put the plug into the coil but not in the engine. If you have jump leads connect the outside of the plug to the negative terminal of the battery or any part of the metal bodywork. If you have no leads then place the plug somewhere it touches metal. Get someone who lives in your house to turn the engine over while you look at the plug. Check for a spark.

If you are getting fuel and spark then check your air intake is not blocked. If that is okay we go beyond the scope of my brain to solve this issue without being there :grinning:

Next steps revolve around checking the timing and various sensors

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Before you do any of that. Try starting the car with the accelerator flat to the floor. This will turn the engine over but will not introduce any fuel. This helps to dry things out when you’ve managed to flood it. I can’t think of too many situations that would flood a modern engine but who knows. Once you’ve done that try starting normally

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Many thanks for your replies, BrilliantBlackBirdy. I took out the plugs and they were soaking wet. Dried them and reinstalled them but still no firing.
I then saw your second reply so tried turning it over with throttle to the floor then releasing the throttle and it almost caught.
Battery starting to get low now so Ill charge it up and try that procedure in the morning. Surely cant be much if there are no codes on the EBD.
I did start it from cold last evening to move the car just a few feet into the car port.
Could that have upset it?

It sounds like the battery is not charged enough to crank it up. I’ve had that on a couple of cars not including the mx5. For the future get yourself a phone charger that goes in the 12v cigarette port. Some of them come with a built in volt meter so you can see if it is low or not. You normally need 12v at the battery and the alternator boosts it to fire up the engine. Make sure you turn off all lights/heating/radio etc that draw on the battery.

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Coming from Ducati ownership, 12v is nowhere near enough for one of those beasts.
12.6v may not sound very different from 12v but in the world of ECUs, it’s an enormous difference, the difference between healthy and perhaps shot…

It’s true, 12v is minimum really and usually highlights failing battery or alternator but if car does regular short runs it never gets chance to properly charge up.

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If you only run a cold engine for a few seconds there is a significant chance of effectively flooding it, simply because modern cars run over-rich to begin with on high tick-over to heat up the cat as quickly as possible.

For the last twenty odd years in petrol cars with cats, if I’ve started a cold engine I always wait for the tick-over to drop to a more normal level before switching it off again, this specifically to prevent the wet plug problem. Once caught, once warned.

The other trick is to wait a second or so for the petrol pump to settle at full pressure before spinning the starter, especially useful if the car has been standing for a few weeks. You can hear it briefly in the NC. This very brief pause helps the engine to fire on first spin, saving wear and tear and prolonging the battery life.

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Sounds like nothing too drastic then. Probably just a battery that’s on the way out. Shame you won’t be able to get a new one for a bit :angry: Hopefully you have a decent charger to top it off with. Good luck with it

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Many thanks for all your useful contributions.
Ive no good reason to use the car today so Ive left the battery on charge and hopefully the delay will allow combustion chambers to dry out fully.
I`ve every confidence that the car will start.
Will let you know.
Thanks again.

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If it’s a wet battery and you have some distilled water, make sure the battery is topped up. It can make a big difference

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Car started normally this AM. Many thanks for all the advice.
It was flooded (due to operator error!).
Won`t happen again.

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Just a thought but I have experience of a classic car which, similarly, refused to start. It turned out that, after some time stting in the tank, the petrol had ‘gone off’ (sorry but the technical term eludes me) - something that is not unusual with modern fuels containing ethanol. Try soaking a small rag or paper towel, take it somewhere safe outdoors and see if it sets alight as enthusiastically as you would expect. Warning; do not try this indoors, boys and girls!

Urban myth?!! I have left fuel in the mini for several years and not had a problem starting it. I appreciate it may not be as ‘explosive’ as fresh fuel but it does not have to be a big bang to start a car.
:heart: