Check engine light blinking and running poorly at idle
 

Recently replaced all ignition coils and an O2 sensor that was throwing a code. All codes associated with that cleared from the permanent codes section of the ECU and my Z was running perfect for 100 miles or so.

Then recently I went to start it and the check engine light started blinking immediately. I noticed a loss of acceleration, like it’s in limp mode.

I’m at a loss because the only code being thrown now is P0300.

I have replaced :
Spark Plugs
Ignition Coils
1 O2 sensor

I do have an uprev cable for monitoring, just not sure where I should start.

Not sure if this would have anything to do with the issues but the car has not been driven a lot over the years. It is a 2010 and just crossed 50k miles.

You may need Idle re-learn/ reset

I went through this procedure but no luck.

I don't know if UpRev is similar in user function to ECUTEK. If so I would reset the ecu and do a once over to ensure all parts were installed correctly and nothing like electrical connections/harnesses have worked their way loose ! Also check for damaged harnesses/wiring around the places you were working. What spark plugs did you install and where did you purchase them from ?

Trying to find receipt, but I went with OEM from autozone. Spark plugs were replaced about 18 months ago. I was reading an older thread on here where a user had water that accumulated in the bottom of his tank. Wonder if that’s a possibility from the years of it sitting often.

It's possible, specially if you use ethanol blended gas and you dont
follow proper storage procedures for gas tanks.

If you are concerend, best way is to drain tank now. Get a bottle of REDLINE S-1 fuel treatment and add it to a fresh fill of gas.

Not sure if there is a drain plug for the Z fuel tank.

You 'll have to drive it for seevral miles to get new gas and cleaner to flow through system and do it's thing.

Just an update, now I am also getting code P0175 Fuel System Rich - Bank 2.

Clean your throttle body and MAF. It may be that in fixing on issue revealed another existing issue. Stillen CAI, any oiled air filter especially if they have been re/over-oiled, can cause oil to get on the MAF and throttle bodies causing the incorrect amount of air to enter leading to random misfires and rich/lean conditions.