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Er no, not them..


After a layup you might experience poor starting and then a misfire

on your Integrale.

A poor electric ignition connection is shown up when the engine runs smoothly at idle or low load, but misfires when you accelerate,

putting the engine under load.

Due to the design of an Integrale's bonnet vents being over the engine, water can drip on to the motor, and then run down the spark plug holes. The holes can fill with water and short circuit the plug leads. On low power the current flows correctly, but under load the leccy will flow the easiest way, which is to earth through the water to the engine block.

Thus a short circuit causes a misfire.

Integrale engine

A misfiring engine may have no outward faults, but the spark plug bores might be full of water

So if you have a misfire, take the spark plug cover off and look down the plug holes first. If you find water, push a rag down the hole with a screwdriver, or blow the water out with compressed air.

Do this before you take the plugs out.

new spark plugs
rusty spark plugs

These plugs were removed from the engine above, you can see they are water damaged,

the plug on the far left has been submerged up to the plug lead cap 

A lovely new set of NGK BPR7E spark plugs about to be fitted,

these are single electrode, standard equipment.

An aftermarket shield under the front bonnet vent will help control this problem 


I've always preferred NGK triple electrode plugs, I assumed they

would be 3 times sparkier. And they look cool!

But it seems the spark only travels to one of the electrodes at a time.

Electronic ignition sparks are hotter and shorter duration than older points system sparks, so the anti fouling properties of triple electrode plug are of little advantage.

It could be said that the two unused electrodes are shielding the single spark, so a single electrode plug is actually better. 

I haven't made this up, it's on NGK's own web site.

So today's lesson, missfire...check plug holes,

new plugs needed...single electrode will do fine.

integralingham t shirt.jpg
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