tonyinclearwater

I did 2-3 searches of the 5th Gen forum and did not see my exact symptoms anywhere.

Also, I did not see a way to confirm that the problem is a coil pack, or identify which coil pack is faulty in the absence of SES light, and absence of any codes being thrown.

Car was not driven for two weeks before problem began. The weather has been cold, for Tampa, Florida anyway.

2003 Maxima Automatic Transmission. 43,xxx miles.

Symptoms;

When the car FIRST starts cold, there does not seem to be a problem. It immediately idles high. I presume this is some kind of cold start normal function.

After the car warms up, the idle seems to level out at about 650RPM.

When I stop at a light, it seems like one cylinder does not always fire.

It seems like after maybe 8-15 minutes of driving the problem stops.

The problem just started today. There were two times today that I started the car when COLD.

The first time I got maybe 1 or 1.5 miles to the first red light and I immediately felt the misfire.

I stopped the car after another mile of driving, turned off the motor, got back in after about 10 minutes, and started it and let it idle in the parking place after putting it in gear. The problem was still noticeable.

After I had driven a few more miles the problem seemed to stop.

I took the car to a local shop where they agreed to waive the usual $19.99 diagnostic fee, and the hooked up their machine to it. The said they checked every way they knew how with their diagnostic machine, and did not see any problem.

The next time I started the car when COLD, about 8 PM, it did not demonstrate the problem at first. I got to the end of my 3 mile or so trip without any problem.

I got back in the car to go home, and right before home I got a couple / few more misfires. I got to my parking place at home, listened for a couple more minutes, no misfire.

It is not so severe that it seems like the car is going to stop running, not even close.

I am banking that this is a coil pack, but if anyone, especially any of the more experienced Maxima owners, or posters here can give me their opinion on the confirmation of this I would appreciate it.

Also... The SES light does not come on, so I presume that if I hook-up my scanner that I got from a parts store, it will not throw a code. (correct?).

If it is a coil pack, will the SES light ALWAYS come on?

If it is a coil pack, is there a way to tell WHICH coil pack without a code?

I have not gotten so far as to take off the engine cover and look at the coil packs, so I have not seen any 'markings' or 'gray dots' on the coil packs.

It seems from what I have read here that there are some OEM coil packs that are inferior, and some that are the newer and / or 'superior' packs. Did any of the 2003 Maximas come with the newer, better coil packs?

I know at least one of the packs has been changed. It was at a local 'Goodyear' earlier this year before I owned the car.

Thanks in advance for any insight into my symptoms / issues.

To those who will say my post is to long, please forgive me. I am just trying to provide as much info that may be relevant.

LongIslandMax

iTrader: (3)

Waxima

iTrader: (3)

Intermittent misfire at idle: more analytical!

sontakke

When it is actively misfiring, just disconnect electrical connector to one coil at a time until you find the one which makes NO difference in running of the engine. That is your bad cylinder/coil/plug.

- Vikas

Rochester

iTrader: (3)

Not necessarily. I've had two original coil packs go on me. The first was 2 years ago, and it failed slowly over the course of 3 weeks. The SES didn't come on until the failure was more prolonged. Eventually it failed completely, and I had the car towed rather than try running on 5 cylinders and really f*king things up. When the second coil pack started to fail, I knew then exactly what was happening, and replaced it ASAP. Fortunately, it triggered a code to tell me which one. And even more fortunate still, it was in the front bank.

My point is: get on top of this now, before it gets worse. It will get worse.

No. Stop it.

williamgd2

I had that same exact problem and it was a coil pack.It took a while but I did eventually get a cel telling me what coil was bad. You could have a code stored without a cel so you might want to get it read. good luck

Mr. Brett

iTrader: (7)

So here's a fun brain-teaser:

My car's misfiring intermittently at idle, too. However, here's the catch:

Sometimes the car will run rough enough to the point that you can feel the whole car shake, and the SES light starts flashing.

If I turn it off and turn it back on, the car with smooth out, for the most part. If I drive the car, it clears up. I took a stethescope to all of the injectors and cylinders, unplugged all six coils and injectors. Every single one caused the car to bog, which makes me figure that they're all good.

What are the odds of a lazy coilpack or injector that's functioning properly 95% of the time, and not the other 5? Or even a lazy O2 sensor causing my problems?

My car refuses to throw anything other than a P0300. It doesn't seem to want to tell me what cylinders.

maxima dude

^^ i had that code pop up on me every month...but my car wuld run fine...got a tune cuz im fully bolted...never came back

Mr. Brett

iTrader: (7)

That's the thing. All I've got are I/TP/E and a NWP BOP. I haven't put my headers on. I'm beginning to suspect that my wonderful, failing precats are partly to blame. I'm wondering if they're somehow messing with the O2 sensors.

Clashez

iTrader: (5)

I feel like my car gets light shakes to every once in a while at idle. Never get a check engine light tho. I can mark out the precats cuz mine are only a month old

tonyinclearwater

Your breif post was more helpful and reassuring than any feedback I had received, or any info I came across.

It seems the problem was in fact a coil pack.

The front drivers side coil pack. If it would have been a rear pack I would have had to get someone else to do this job for me.

The one I changed looked different than the other two in the front bank.

The one I changed had NO markings on the top of the coil, while the other two had a gray 'oval' about the size of a pinky fingernail.

I was VERY concerned that this problem would be difficult and time consuming to diagnose, and possibly costly to fix.

I had a couple mechanic buddies lined-up to look at this with me, but they were stalling, postponing, and dragging their feet.

I had bought one coil pack with the intention of trying it on the first cylinder BEFORE starting the car, and changing the location of the coil pack while the car was still relatively cold until I found the bad coil pack.

I woke up this AM and asked myself 'how hard could it be, especially if it turns out to be a FRONT cylinder'?

I rummaged around and found the correct size alan wrench to remove the engine cover. I noticed the front left pack looked different, and i figured that must be the pack that Goodyear replaced earlier this year before I owned the car, and that Goodyear would likely use the cheapest crap available. I started with that coil pack, and that was the one. I started the car, let it warm past the cold-start high-rpm's and it did NOT misfire.

It appears my problem is fixed. SO GLAD.

I hope this thread helps another maxima owner in the future that is having the same problem.

Thanks to all who contributed and / or gave any feedback or advice.