I read the right up on missfiring but I have a question. My car only seams to missfire when the A/C is on. I know the A/C puts the car under a load which makes it have to work the engine harder but recently it's been getting worse and today it is getting really bad. But again it only seams to do it when the A/C is on. I'm gonna check my plugs and wires and see what I find but I wanted to see if anyone else has had this problem.

Also, if one of the coil packs goes bad is there a way to tell it or is that one of those things where you just replace it and see if the car gets better?

 

if one of them truly goes out, the ECU is going to light up the CEL, you can go to most any auto parts store and have them read the code. AFAIK it will even tell you which pack it is then.

 

Cool, that's good to know.

I just finished check my plugs, wires-boots, coil packs.... everything looked fine but oddly enough the spark plug gap was way off on all 4 plugs. the 1st and 3rd were at like .050-.055in and the 2nd and 4th were both over .060in! The 4th was the worst! The plugs looked like they were probably the stock ones... They said NGK R on em. I only have 53,000miles on the car but they definitely looked "golden brown"... gonna go ahead and replace em with more NGK's from Advance Auto.

One more thing that caught my eye though and I think it was only plug #1.... an 1/8 of an inch of the ceramic closest to the nut part of the plug had been BURNT black all the way around. I'm pretty sure it was only the first one. Never seen a plug like that before. It wasn't cracked or anything but it definitely had me worried. The flat end of the boot on that one was the tiniest bit orange too so I'm thinking maybe it has or is arcing there.... I don't know why it would be cause the boot is on good and you can here it clip onto the plug.

 

Change your plugs. That's a looot of miles on the stock plugs. Let us know how it goes afterwords.

 

Well, good news. All I had to do was change the spark gap to what it was supposed to be (set em to 0.040in) and just put 50 miles on it.... not one missfire! Though I am gonna change the plugs. What type plugs do you guys recommend for the 02 Lancer? It has NGK R's in it... the guys down at the parts store said those were only like $2 each but they recommended the NGK iridium plugs which were $6 each. Will there be any difference at all? Should I just choke down the extra money just for the heck of it?

 

not true. i had a dead pack and the only code i pulled P0300 Random/Multiple Cylinder Misfire. my car was literally running on 2 cylinders and i still never got a code that said it was a coil.

 

ok, thanks for the info. Tho I find that very odd, why wouldn't they do that? oh well, I'm not an engineer.

 

you're welcome (sorry if i sounded rude earlier). i thought it was really odd as well. it would make things much simpler...then again that is probably the answer.

 

Get the cheapos. You're not going to need the Iridium plugs. Of course they recommended the expensive plugs - it's how they stay in business!

 

Ditto - stay with the NGK Copper BKR5Es - these plugs work great and there is no reason to get any others.

 

I always get the coppers. Work great and I change them every 10,000 miles.

 

Heh, well it's a little late now. Just put the iridium plugs in about 30 minutes ago. Car is running great now. I hope this helps improve my gas milage.... I covered about maybe 60 miles yesterday and used a 1/4 tank of gas! They were highway miles too! I was ticked. Should be fine now though.

Thanks for the help fellow brethren!

 

No problem dude. Good to hear everything is back to normal.

 

so the CEL went out ? and what do you mean by

spark plug gap was way off on all 4 plugs. the 1st and 3rd were at like .050-.055in and the 2nd and 4th were both over .060in! The 4th was the worst! The plugs looked like they were probably the stock ones...

i have this CEL problem too an i dont see why is still there i have iridium plugs and magnacore spark plug wires help me out

 

- he's saying the spark plugs were gapped to far. the lancer is supposed to be set at .044 therefore, whether he was at .05-.06 OR he was gapped .05-.06 OVER...either way its a problem....keep it a .044

-what codes are you pulling from the CEL?

mark