Yah Iam going to pick some plugs up tonight...

I already have the NON foulers in the test pipes but its still throwing a cel out.

My mods are:
Nismo Exhaust
Kinetix Test pipes
DC Headers
Nismo Cams
AAM Plenum Spacer
UR Pulleys
JWT intake
Technosquare reflash

 

If you have two non foulers for each o2 sensor then the cel shouldnt be thrown. Its most likely another cause that is throwing it. Your best bet would be to replace the plugs, reset the ecu and find out what happens.

 

Luke,

What is the exact code being thrown? I would replace the spark plugs just to be safe and make sure they are gapped correctly. Just to get this correct, was your first dyno result (the high one) done before you had your ecu reflashed?

Thanks,

Jermaine~

 

Yes the 278 was my first dyno two months ago... then it started throwing codes and runnin like crap ... I will get the codes tommorrow to try and post them up... the Advanced cam timing code was the most interesting one I found.

 

Wow this sucks to hear. Subscribing to see what happens after the spark plug replacement.

I thought the Technosquare reflash prevents the ECU from re-learning and re-adjusting??

Doesn't make sense to me why you're back to stock numbers... Except for the #5 cylinder miss fire code and advanced timing code, perhaps this is an indication of a problem with your cams?

Maybe you could mix some 100 octane in and see the result? Maybe the technosquare reflash gave you too advanced timing?

Just throwing some ideas out there, I know I'm not the most experienced guy when it comes to this stuff but I'm trying to help

 

um, yea, I think there's another reason why you're losing power and it isn't because of the ****ty ECU.

 

If your suggesting its his head gasket I suggest you are incorrect. Head gaskets only blow because of two reasons, 1) overheating 2) Too much boost with a weak head gasket. He is N/A so its not boost, and i'm hoping he hasnt over heated. If he replaces the plugs and he still has a misfire, I say its his coil for #5 cylinder. But what do I know.

 

But i used to be boosted.. And the car has overheated once before due to air needing to be purged very recently.. I was on the freeway with no shoulder and could not pull over for 1 mile .. If it does end up being an head gasket I will return the car to stock and bring it to the dealer to check it out. Only thing Iam worried about is the erratic idle of the cams giving away the car has some internal mods.

 

What type of cams do you have? Any specs? If it is very mild, you might get away with it. Good luck

 

There Nismo.. but it still idles like a chevy lol...

 

replace the spark plugs as stated above. if not buy a new coil pack.or buy the ones on ebay. like 6 for 80 bucks.

 

Can you swap the coil pack from a different cylinder to see if it follows the coil?

 

yes

 

Well to update you guys incase this same thing happens to someone else..

I put in the new spark plugs... Moved coil from cylinder 4 to #5. Started it up, reset the ECU. Same code... misfire cylinder #5. So I thought .. maybe an injector is stuck open... I then took off the Cat on the #5 cylinder and found gas just sitting in the cat. So now I have to figure out if this is def. the problem.. Working on it more within the next 15min. Anyone have suggestion to be sure this is the problem?

 

I don't want to have to tune anything. I wish I could just plug something in, or hit a button that automatically put the car in racing mode or economy mode.

 

Have you put it on a scope yet? check your HC CO O2 CO2 NOX readings. maybe that will help your diagnosis a bit. its just an idea. or maybe a short somewhere in your injecters causing it to stay open. also if you can check your PWM to check your on and off time. if not then a new injector. once again just an input. hope it helps on your diagnosis. good luck man. now i need to figure out why my car pings!

 

I'm having the same issues you do but without codes which makes it 10 times worst lol.