It just started today, while driving back home from work once engine got warmed up, idle was rough and couldnt keep stable. Once I got home and parked in the garage it got worse and the check engine light randomly started flashing. I'v read somewhere that it could be misfiring. Am I right?
Could the problem be ignition coils and wires?
By the way, the I heard the exhaust backfire randomly as well (on idle and warm engine)

Here are some things about the car
The engine was replaced by dealer at 32K, so it only has about 2.5k on it right now
Car has 35k
oil needs to be changed in couple hundred miles
Its all stock
The engine has not reached above 4000 rpms untill it had 2.5k

 

check my thread, i had a similar problem with my car....i just replace the coils, wires and spark plugs and done, fixed!!.....im 90% sure that if you do that (replace that parts), your car will be normal again

 

Nevermind, I took the car to the dealer today,a and what turned out is that it had wayy too much carbon buildup, causing it to misfire. Appearantly what caused this was improper air/fuel mixture, which I believe was because of removing the 2 sidewalls from the inside of the intake box.....

 

/\ that was a good story from your dealer - don't believe it ......

 

In that case, what could cause it to have so much carbon buildup?
They haven't mentioned anything about the sidewalls, that was just my guess since i did it like 400 miles before the problem. But they did say it had bad air/fuel mixture.

 

a dirty maf sensor could cause rich mixture .
Do you redline regularly ?

 

+1

It never ceases to amaze me the B.S. that car places tell their customers.

However....

Make sure the screens are intact in the airbox horn. Missing screens can/will screw up the airflow readings at the MAF sensor.


G/luck.

 

I think i just found your problem ..........

 

Yeah, make sure to get your motor above 7800RPM as often as safe/possible. Have fun with your car, but don't drive recklessly. You've gotta keep the heat up in there to burn off the carbon, or else this will happen. I'm sure it can also kill cats(I recommend you get that checked out too).

 

Ok I just got back from the dealer, i got a better explanation of the problem.
The carbon buildup caused poor air/fuel mixture. To fix this all there gonna do is clean it up. It was my assumption that it could have been because of the intake. I was wrong, noob mistake.

Ever since the engine was broken in, I redline it daily.

 

Sorry to bring up an old thread but I'm having issues with my car. It started stalling out about two weeks ago. Changed out the coils, wires, and plugs. Car still idles rough and at times won't recline. I've tried running it hard to blow out the carbon but it's not really working. Car feels more sluggish than before. Today no stalling when driving but a few times it acted like it was choking out when trying to rev while driving. I also had the check engine light start flashing and several times the light saying I need coolant or it was hot come on but it's not and doesn't need coolant. Any ideas?