Diagnosis needed: Car stalling on start up
Posted: Mon Jan 04, 2010 11:24 am
Fuel, air & heat (combustion triangle) - see Rotary's excellent posts:
Another easy way to check if it's fuel related is to turn the engine over a few times & then immediately remove a spark plug to see if it's wet from fuel.
Air might seem to obvious, but it's worth checking there are no major restrictions, especially if the car is a recent purchase or has been worked on recently. Just after I bought my old NA6 I found an old cloth had been sucked into the airbox snorkle.
:Rotary wrote:Have you checked for spark?
That way you know for 100% certainty that you have an electrical/Ignition fault.
If there is spark then its almost certainly fuelling related unless the plugs are foul or spark is not regular.
:Rotary wrote:Can check spark a couple of ways.
By putting a new spark plug on one of the leads and making sure its metal (side or base) is earthing, anywhere there is a good earth connection(usually an exposed bolt attached to the chassis or the inlet manifold).
If your unsure and have a multi-meter then check it, otherwise you could damage something.
The other way is if you have an old ignition lead with end exposed, that will work without a spark plug but you must keep a 1cm gap between it and earth.
Then just turn the ignition and watch or listen for loud snapping noises.
Just need to be certain there’s no fuel leaks or spilt fuel anywhere as it may ignite it, so if there a strong fuel smell then don’t do it.
Or without checking for spark, you can just get a can of Starting Fluid, from any Autoshop, and spray a good amount in the throttle body, with it on full throttle, then try and kick it over.
If there is any kick or it starts briefly, it has spark and no fuel, no kick at all, will most likely mean no spark (so electric or ignition issue).
Another easy way to check if it's fuel related is to turn the engine over a few times & then immediately remove a spark plug to see if it's wet from fuel.
Air might seem to obvious, but it's worth checking there are no major restrictions, especially if the car is a recent purchase or has been worked on recently. Just after I bought my old NA6 I found an old cloth had been sucked into the airbox snorkle.
