about a week ago i let my friend drive my car and he stalled it out three times on a hill at a light. the cel came on and stayed lit. the code said 1st rotor misfire detected. i turned the light off assuming it missfired when he stalled. the light never came back on but the car still has a rougher idle than before. it seems just fine when driving under any acceleration but at idle it only spins about 750rpms and has a more distinct roughness.

upon research i would assume he fried a coil or fouled a plug. the car has 48000 now is it time for these anyway? are there any other solutions to this problem? why has the cel not come back on? is it safe to drive the car?

thanks for any info.

 

I would say its safe to drive, just don't "hammer it " like redlining it.
Spark plugs would definitely be the first thing to change out.
Followed by coils and/or ignition wires.
Another thing you might want to check is the ignition wires to the front rotor.
Make sure none of them came loose from the spark plug... its been known to happen.

 

i have been looking at the bhr ignition upgrade do you think this rout would solve my problem?

 

If you get the BHR coils, also purchase the spark plugs through them too.
Chances are this will correct your issue.
But like I said, your issue can also simply be a loose connection to the spark plugs.
It seems more common with the front rotor too.

 

thanks 316 i checked the wires this mormimg and they seemed to be plenty tight so i guess im still looking at replasing the ignition rite? what about cleaning the maf? could that be part of my issue?

 

bump...

 

You know... it probably took you more time to get online and bump your thread than it takes to remove and clean the MAF... so why didn't you just do that instead of waiting?

And since its misfiring for just one rotor... I would say its less likely a dirty MAF.
BUT... since it takes such little time to do... why not!

 

Yep, clean the MAF and re-set the ECU.

 

haha man i know its easy but its cold. plus i was at work but i got the cleaner and some tb cleaner too so im gonna try that stuff tomorrow. ill let you know if it works... i will remmember never to bump again haha.

 

when it came time to replace coils I went with the BHR complete ignition set.
coils,plugs and wires.......very very good purchase!....I highly recommend them.

 

I'm going to agree with Jon on this one.
Typically in a situation like this you need some form of process of elimination:

- Loose spark plug wire? - nope
- Dirty MAF? maybe but most likely not the culprit. wouldn't hurt to clean Remember, just lightly spray it with MAF cleaner, don't touch it with anything.

- 48,000 on original plugs? - definitely replace, they're only good for about 36k
- Coils: you could try testing each coil with a multimeter if you have access to one or you could just swap them out as you're considering it anyways. BHR will cost you a bit more but should last much longer then OEM coils.

 

so here is an update for anyone that may be interested... apparently my "non-driving" buddy doesnt appear to have aything with the issue. also my car apparently is not missfiring at all. my friend who is is also pretty much my personal mechanic took my car today and ran it on a snap-on MODIS and graphed the whole opperation of it. the MAF, coils, TPS, ESPS and everything about the engine was perfect. the problem he found was in my upstream o2. it read negative voltage between 0.078 and 450mV with AFRs varying 18:1 to 22:1 respectively. also the short term fuel trends bounced back and forth between -20 and +20%. now as i assumed these variables only showed at idle. once any load was introduced and the upstream cut off and the car went on open loop the AFR went back around 13.5:1ish and everything else was fine. the diagnosis is a bad o2 $375ish of a short to ground from the wires being pulled out by me straddling 6" of snow and ice on my gfs road for 2-3 weeks or a rodent seeking warmth and getting hungry for some wiring harness. so if any one knows a cheap place to pick up a primary o2 for cheap please let me know haha. i will update as soon as i know more.

 

so anybody have any ideas or coments about this? we found nothing wrong with the wiring on the o2 and the car leans out whenever the rpm stays consistant. im confused. and my friend is getting angry that their are no pistons under my hood and keeps saying he has a engine and tranny from a firehawk laying in his shed hed sell me. help!