Spark Plugs becoming faulty when Air Con is Turned On

[VTSSDUDE]

Hi,
I have a friend who when is driving around town, if he turns the air conditioner on, his back two cylinders (V6) spark plugs let go, that the engine only runs on 4 cylinders, he then has to have the spark plugs replaced. Now if he uses the Air Conditioner on the highway, he has no problems. His mechanic just says this is a common fault with the Series I VP Commodores.
I just can't think of what could be causing this problem?

Thanks,

[mouce]

I'd say find a new mechanic. I've never heard of that on ANY car.

[ashzv6]

im interested, wat do u mean let go?
u mean the plugs fall out the block or break?
are the spark plug threads allright?

ive gotta problem with my no1 plug/lead

once a month the lead will pop off the plug,
and sounds/runs like a 50 year old yank tank

i beleive this is due to the lead.

[mouce]

^^^If you're dropping leads like that, just get a new set, they don't cost that much.

[defa]

thats sounds a little bit strange.. even if there was some sort of electrical fault how could that stuff up ya plugs. that just doesn't make sense at all..
also what do you mean by the spark plugs letting go..

[VTSSDUDE]

Well, the dude that owns the car isn't very mechanically minded, all he knows is the mechanic has to replace the back two spark plugs. I just assume they stop working, which doesn't make sense, and yes I thought too as how can an electrical fault fail a spark plug?

[immortality]

sounds like you mean fouled plugs??? need more info

[VTSSDUDE]

Yeah problem is his mechanic didn't or doesn't tell him exactly what happens to the spark plugs just says they need replacing, mind you this has happened more then once.
He know just doesn't use the air con around town.

[immortality]

I'd say find a new mechanic. I've never heard of that on ANY car.

you nailed it here