Coils Or Not Coils?

[xr6_2001]

Been chasing a issue (well a few) with my ba 04 xr6t, but most recently, my car has been stuttering when I give it a bootfull around 3k rpm, straight away thought coils.

However over last weekend I pulled one out at a time and put a screw driver in each coil turning car on and off one at a time, found that 2,3,4 don't seem to have to same amount of spark as 1,5,6. pulled the end caps off each coil, and the bottoms of all of em all have hair line cracks, so I thought this weekend I'll replace em all.

Untill today here in Adelaide it's abit warm so been driving around with the air-con on, and had to put the foot down abit through a orange light and it didn't stutter, pulled up around the back street gave it abit of stink and reved all the way to redline without stutter, turn the air-con off and get the stutter back? WTF!

[Power Jet]

Hi,

some thoughts for you. I have had a problem with my coils the last week. When I was giving it half a boot the car would backfire and I would get the ticking ping. Clearly post-detonation.

When the coils are not working properly and when I say not working properly it could be 1 is only working at 90% it does not send enough current? through to the spark plug and does not ignite the air/fuel mix completely. This only happens for a split second before the rest of the mixture detonates in the cylinder, hence causing your stutter. Is your stutter backfire? You should be able to hear it pretty bad.

I replaced my coils on Tuesday just gone and man... what a difference, now I can use all my 381rwkw. Another thing to check would be your fuel pump?

And to answer your last question the reason it doesn't do it with the air-con on is that the air-con drains power out of the engine hence dropping your power and slowing things down a tad.

Things to check/change for piece of mind.

-Check for fouled spark plugs. the NGK bcpr6es is pre-gapped to 0.8mm (perfomance application) this would be a good replacement, I picked them up at super cheap for $4.50 each.

-Check to make sure that your fuel pump is not getting lazy. What pump is it?

-Change your coils. I bought a set of ebay a year ago for $165. But have put the genuines back in now.

P.M me if you want anymore info as when this happened to me it did my head in for a week

Marty