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My car ignition turns over but it won’t start. Is it flooded?

You’ve moved your car a couple of metres into your car port or garage, turned off the engine after a few seconds and now it won’t start again – it just turns over without firing. Don’t keep trying to start it – it’s almost certainly flooded, and pumping more fuel into it will just make it worse.

When your engine is flooded it means that there’s too much petrol and not enough oxygen in the engine. This makes the spark plugs wet and they won’t ignite the fuel.

If you’ve only just moved your car a few metres, it’s very common that it won’t start immediately. If you have left it sitting for a while, then it may be OK as the excess fuel could have evaporated. If not, you may need to have the car towed to a garage to clean the spark plugs (or you can do it yourself if you know how and have the right tools – usually a socket set and some spark plug cleaning fluid). In some cases you may need to replace the spark plugs.

If you don't know what the spark plugs are in this image, you probably should ask someone else to clean them

If you don’t know what the spark plugs are in this image, you probably should ask someone else to clean them

You may need to clean your spark plugs if you have flooded your engine

This is what they look like when they’re out of the engine block.

If you do need to move your car a short distance, let it idle for a minute or two in order to burn up the excess fuel and reduce the risk of flooding.

How to get your car started if it’s flooded

This method usually works: push the accelerator to the floor to get as much air into the engine as possible then crank the engine. It might take 10 seconds of turning over before it fires, and it could be lumpy for 10 or more seconds afterwards while the air/fuel ratio levels out.

This might not work in some modern cars if they have electronic throttle control, in which case you’ll need to contact your mechanic.

Darren is a member of the Institute of Advanced Motorists and the NZ Motoring Writers' Guild

Posted in Advice
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