Plug coil replacement

[oceanwind55]

2002 corolla started running rough so I put in new plugs. Made no difference. head down to the auto store and hooked up the engine light checker and it says #2 cylinder misfire. Auto parts store guy says it's probably the coil if I just replaced the plugs and that didn't work. (this model apparently has a coil for each plug) The car has 140K on it so this sounds logical to me. I buy the coil but I'm not sure which cylinder is #2 ???? (yeah, I know...I'm an idiot)

so... which one is #2 if I'm standing in front looking at the engine?? 2nd from left or right?

[Buurin]

Second from left.

[oceanwind55]

Thanks burrin, but I'm confused. Your post in the forum says second from the left but the email notification I recieved that someone had replied say's second from the right. Did you edit the forum post after posting?

[lexusk8]

I believe second from left means the 2nd plug from the passenger side if you are standing in front of the car facing the engine.

[fishexpo101]

A sure fire way to see if it the coil - swap the suspect coil with another and drive the car. If it is a coil problem, the misfire should follow the suspect coil. Don't want to see someone spend money on a part that may not need it. A misfire CEL can be set by a number of things - coil on plug is one of them, heavy carbon deposits, stuck injector, low compression, etc. - make sure it is the coil before you spend money on it. As I doubt the autoparts place will take it back, if it don't fix the problem (if they will take it back, get that in writing).

[MacktasticSlick]

My 99 has 65001 miles on it. Sorry, off topic just like Hummer. lol

[Chris Corolla S]

Well I guess your question was answered but it sweems kinda jumping the gun to go strait to the coil pack. Is the car pinging (pre-detonating) at all? They usually are if you get a missfire code.
#1 one thing i would do was make sure you have a newer clean airfilter. Then I would thoroughly clean the MAF. A dirty airfilter and MAF gave me a missfire in cylinder #1.

Then I would test the main oxygen sensor. I would test/replace replace the fuel filter and oxygen sensor. Also there is a way to test the coil pack with a multi-meter to see if it is working right before just buying a new one.

Hope this helps! Chris

[01loadedLE]

Originally Posted by MacktasticSlick

My 99 has 65001 miles on it. Sorry, off topic just like Hummer. lol

And I thought I was doing good at 95k on my 01.

55 it takes a lot more to be an idiot than not knowing where the #2 cyl is at. Some people know and theyre still idiots.

[Buurin]

Originally Posted by oceanwind55

Thanks burrin, but I'm confused. Your post in the forum says second from the left but the email notification I recieved that someone had replied say's second from the right. Did you edit the forum post after posting?

Yeah it should be second from the left. Typing ahead of myself did it.

[oceanwind55]

Originally Posted by Chris Corolla S

Well I guess your question was answered but it sweems kinda jumping the gun to go strait to the coil pack. Is the car pinging (pre-detonating) at all? They usually are if you get a missfire code.
#1 one thing i would do was make sure you have a newer clean airfilter. Then I would thoroughly clean the MAF. A dirty airfilter and MAF gave me a missfire in cylinder #1.

Then I would test the main oxygen sensor. I would test/replace replace the fuel filter and oxygen sensor. Also there is a way to test the coil pack with a multi-meter to see if it is working right before just buying a new one.

Hope this helps! Chris

New air filter and plugs about a month and half ago, (whats a MAF?)
I already bought a coil (haven't installed it yet) also , if the coil doesn't fix it would the O2 sensor be the next logical step? about how much do they cost? Is it something I could just swap out? (I don't even know where it is yet)

TIA

[Chris Corolla S]

Definitley swap the coil pack and see if that works. It should take you all of 5 minutes as you know if you already pulled the plugs. A problem in the ignition sequence of only one cylinder is why you go to cylinder speficic things like plugs and coil packs so that makes sense. But sometimes I've found general problems with air fuel ratio will show up in a code for only one cylinder for some reason. The MAF is the mass air flow sensor. Two bolts hold it on your airbox do a search to see how to clean one. O2 sensor is not cheap about $100, it's on the exhaust manifold down low, it's kind of a pain but it's a strait swap. That's the primary one then there is the secondary, or post-cat one after the cat. You can probe the o2 sensors with a multi meter to see if they are functioning within range. If you want to try and work on it yourself I suggest buying a haynes manual and doing some searches here on TN using the missfire code.

PS when you say running rough do you mean running on three cylinders or just hesitaiting or what? What does it sound like?
-Chris

[oceanwind55]

Well I installed the coil on #2 cylinder and it made no difference (also installed another new plug just to make sure I didn't get a bad one)
The car is definately running on just 3 cylinders. (#2 being the bad one)
I cranked it up and while it was running disconnected the electrical connector to the injector. Made no difference in the way the engine ran. hooked the injector clip back on and then disconnected the connector to the coil and again it made no difference to the way it was running. (doing this to any OTHER cylinder and it immediately went to running on just 2 cylinders, so I'm sure the number 2 is not firing at all) The #2 plug appears to be a little wet so I kinda think the injector is squirting. (but not 100% sure)

Is it OK to take the plug/coil out and turn it over to see if the plug as actully firing? If it is and it's firing, Should I try to swap the injector over to another cylinder and see if the trouble follows? (since I already bought the coil and I don't think they'll take back an electrical component)

I'll go ahead and clean the MAF first, but would that just effect 1 cylinder like that???

[Chris Corolla S]

Originally Posted by oceanwind55

Well I installed the coil on #2 cylinder and it made no difference (also installed another new plug just to make sure I didn't get a bad one)
The car is definately running on just 3 cylinders. (#2 being the bad one)
I cranked it up and while it was running disconnected the electrical connector to the injector. Made no difference in the way the engine ran. hooked the injector clip back on and then disconnected the connector to the coil and again it made no difference to the way it was running. (doing this to any OTHER cylinder and it immediately went to running on just 2 cylinders, so I'm sure the number 2 is not firing at all) The #2 plug appears to be a little wet so I kinda think the injector is squirting. (but not 100% sure)

Is it OK to take the plug/coil out and turn it over to see if the plug as actully firing? If it is and it's firing, Should I try to swap the injector over to another cylinder and see if the trouble follows? (since I already bought the coil and I don't think they'll take back an electrical component)

I'll go ahead and clean the MAF first, but would that just effect 1 cylinder like that???

If it's running on three cylinders no that wouldn"t be the MAF, it might still need to be cleaned but getting the #2 cylinder to fire is priority. Yes i think swapping the injector is a great idea, but it kinda does sound like you still aren't gettting a spark. I think you should do a compression check at this point if it's not the injector. Expecially considering the rings and valve seats tend to go on these motors. You need spark, fuel, and compression to get an explosion. I don't know if you can remove the plug while it is firing? Do some searching on how to confirm you have spark in a given cylinder.
-Chris