Inconsistent starting

Brussels Sprout

I drive a '04 Focus. Quite often when I turn the key the engine takes a second or two to fire up. The starter motor will turn the engine but it doesn't kick into life. This doesn't happen every time-maybe once every third or fourth time.

It never really bothered me too much as it always started. However tonight it didn't. I had the key turned for 3 or 4 seconds and the engine went round and round without firing. I tried this 3 or 4 times. I then took off the hand brake and rolled the car forward and tried again and this time it spluttered and came to life.

Two hours later it started perfectly first time.

Any ideas-sparkplugs, carburettor-? Should I be taking it to a mechanic or this this likely to be something I could do myself?

jca

If you think your car has a carburettor you should bring it to a mechanic.

biko

What jca is trying to say, in a less than helpful way , is that your car doesn't have a carburettor. Modern cars use fuel injection.
But you're not too far off. It sounds like it could be an issue with fuel delivery or plugs.
Fuel pump/filter/injectors maybe.

What you can do to test is buy some start fluid in a factors.
Crank engine, if it doesn't start spray a little fluid into the intake. If car fires up then it's the fuel system not delivering properly.
If it still won't fire it's the spark plugs/electrics.
Or something else entirely.

This is a petrol car yeah?

jca

Any vehicle that doesn't start it's a problem with fuel or plugs... Don't use those starting sprays they can cause a lot of damage particularly in petrol engines. Easier to bring it to someone who knows what to do.

Brussels Sprout

Yes this is a petrol engine

biko

Instead of starter fluid you could get carburettor* cleaner and use that. It has more uses around the car like help diagnosing vacuum leaks or cleaning things.
Carb cleaner is a solvent so take it gentle with the amounts and where you put it.

*badum tisch

Here's how it works
http://www.youtube.com/watch?v=EBhdxem2toA

Note, this is what I'd do - if you don't feel confident to DIY it, take it to a mech. But hey this is the DIY forum innit..

sandydan

had similiar problem with opel for two months discovered it was fuel tank vent blocked ,cleaned it and problem solved, to diagnose take off tank cap before starting or better still after stopping engine (bit of nuisance, but simple),you might hear air going into tank or car will start first time every time. also had joiner hoses in fuel lines feed & return( cant think of correct name, kind of cloth type material on outside) secured by clips that became poros and had to be replaced. an uncle had problem with some unit getting damp in a Dsl C-max and had to get dealer to sort it .sorry cant help any further

jca

When the car is not starting, lift the bonnet spin it over on the starter then have a good sniff around for petrol fumes. Take one of the spark plugs out and check if it's wet. That will tell you if it's getting fuel. If the fault occurs when the engine is hot the primary suspect is the crank angle sensor going open circuit and returning to normal when the engine cools.