before anybody says anything, i did a search and came up with a couple possible diagnosis...but nothing concrete

basically i woke up this morning and went to the gym with no problems...when i turned the car on to come back home i noticed it didnt start normally and then had quite a noticeable shaking idle...also as i started out the car didnt sound the same on acceleration either
i have a budget exhaust (CA spec) w/ greddy catback and as you all know, your car has a distinct sound and it just wasnt right...my SES light comes and goes and everytime i check it, it shows up as a P0420. Its been on but for the first time today the SES light was blinking as i headed home

oh and my car is at 99.5k miles

so i was thinking maybe i blew my MAF, but the car didnt die even while idling at a red light
so then maybe ignition coils?
maybe motor mounts or the bushings?

any help would be greatly appreciated
thanks guys

 

P0420 usually a clogged cat.

Disconnect your MAF at idle and see if it clears up. The ECM goes into "limp/default" metering and should idle good. If the idling is still bad, the it's prolly the cat.

 

The root cause is the engine missing. Ever replaced the coils? Go with the easy stuff first.....air/vacuum leaks, then go for the spark plugs.

 

its something ignition related...probably a bad coil...one or more cylinders isnt detonating

 

hey thanks for the responses guys....im gonna take a look at all those things;
but a little more updating information

so about 2 hours after i got home from the gym i went to go try the car out again and no problems whatsoever
the vibrating was gone, as was the abnormal engine/exhaust sound

my dad was able to get his hands on an OBDII
and i pulled up some codes...since it was my first time using it im not sure if i used it correctly but this is what i got
Read Codes:

P0138 O2S Hi volt (Bank 1 Sensor 2)
P0139 O2S Low (Bank 1 Sensor 2)
P1320 Manufacturer check

and under Pending Codes:
P0306 Misfire detected (cylinder 6)

so it looks like combination of ignition coils and O2 Sensors?
before i take it to my dads mechanic jst wanna know what im expecting
thanks again guys

 

I thought P1320 was multiple cylinder misfire, I could very well be wrong though. I'm throwing a cylinder misfire code and I just received my coils tonight from Dave B. They were 395 shipped for all 6 updated (grey dot) coils. You might want to get them from him if it does end up being the coils

 

P1320 is actually the Ignition Signal code, very often seen with a duff coil. You've also got the clincher......the P0306.....change the No. 6 coil. Forget the O2 sensor. If you're going to hang on to the car a lot longer and the coils haven't been changed out already, change them all. Remember when troubleshooting........change one "thing" at a time.

 

its a bad coil...since the cylinder didnt fire, the exhaust was rich because of unburned fuel. thats what the O2 detected.

 

you guys are awesome, thanks a lot
i appreciate it greatly

 

i've had this... like they said.. it's misfire
new coil time

 

I'm having the same problem as MaxedOut2g. Since coils are pretty expensive (if I were to buy 6 of them), I was thinking about finding the failing coil and changing only the particular one. Nissan Dealer told me to replace 6 coils and 6 spark plugs but the mechanics I go to says that I probably need just one coil to replace.
Any comments are greatly appreciated.

 

When my coils blew, my SES was blinking too.

 

blinking? i've never seen mine blink. it goes away sometimes (for few days) and comes back on whenever it shakes.

 

You need to change out all your cols before your engine takes a crap on you just get a hole set of ebay for like 300 bucks. Once one fails the others will follow just replace all at once and be done with it.

 

contact davb about getting a set (that you know are good). dont buy something like this on ebay, you dont know what you will get.

 

The SES light will blink sometimes, if the ignition coil fails for an extended period of time and the light will remain on when the failure stops. Even if the SES light goes off, the code is still stored in your car unless you clear it. And at different times, the Slip and TCS lights will come on. Whatever the case, if your experiencing the same symptoms as described as the others, its most likely your coils and it's much safer to replace all 6 with updated coils and be done with the problem completely.

 

Thanks for the advise. Will replace 6 of them. Should I replace the spark plugs also?
I have 130k miles and I think I have the original coils and plugs.

One thing I noticed is that sometimes it would shake like it's pulling forward and backward when I accelerate when the engine is cold. Once it gets warmed up - normal. I imagine the behavior is resulted from the bad coils.

 

Might as well since you're already in there. And please don't ask why kind/type/brand etc.

 

I'd replace the plugs too if i were you, @ 130k they've probably seen better days.