NBA Hard to start when warm

Engines, Transmissions & Final Drive questions and answers

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simie2014
Fast Driver
Posts: 310
Joined: Mon Nov 10, 2014 10:02 pm
Vehicle: NB8A

NBA Hard to start when warm

Postby simie2014 » Wed Aug 05, 2015 8:24 pm

Recent trip has revealed that my 2000 NBa needs quite a bit of cranking to start when warm. When i think about it it it's hard is to start when cold. My same age Corolla fires up comparatively quickly hot or cold. Recent trip revealed 36.7 mpg which I was pleased with.

93_Clubman
Speed Racer
Posts: 11854
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: NBA Hard to start when warm

Postby 93_Clubman » Tue Aug 11, 2015 4:21 pm

Sounds like something is on the way out - most common on the NB8A is:
coilpack;
EGI relay;
cam angle sensor;
crank angle sensor; &
weakened wires in wiring loom near coilpack due to being bent without support.
To possibly help you with diagnosis:
93_Clubman wrote:Fuel, air & heat (combustion triangle) - see Rotary's excellent posts:
: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.


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