Hey guys and gals, not sure what to do next. I got a blinking SES light with the P0300 code and after reading online for hours I took it to a shop to get all spark plugs, all 6 coil pack, and fuel injectors replaced.

The check engine light still comes on and blinks with the P0300.

What should I do next? Sell it?

 

I'd try cleaning the mass airflow sensor & check for vacuum leaks. The intake couplers seem prone to cracking in my experience.

 

Did this problem just randomly pop up or did you buy the car with the SES light on?

Fuel pressure test, you will need a sandwich adapter like the one sold by Z1 Motorsports.

Compression test.

 

Sounds like the shop didn't follow the proper diagnostic procedures before throwing parts at it. Have you gone back there yet?

 

(Highjack) I've been having the same problem with P0300 for almost two years. I'm at 205k miles (Yikes). Mods and replacements:

• NGK Iridium Spark Plugs (replaced)
• Fuel Pump/Sending Unit (replaced)
• Original Fuel Injectors (cleaned)
• Original Coil Packs (with F mark) (Checked, no swelling)
• Z1 Plenum Spacer (mod)
• Z1 High Flow Cats (mod)
• Z1 Fuel Pressure Adapter w/Pressure Meter (mod)
• Z-Tube Intake (mod)
• K&N Air Filter (mod)
• 350z Y-pipe (mod)
• Z1 Aluminum Coolant Bleeder (mod)
• Koyo Aluminum Radiator (mod)

Sometimes, rarely, the light goes off. Often times, it's when my oil starts to get low. Sounds like like a Valve Cover Gasket, right? However, when I check the spark plug wells, they're clean. (I'm not ready to drop $400 on the VC gasket kit)

ok, pulled spark plugs and saw this in cylinder 6 spark plug well.

 

You might want to check if there is a short in the main wire harness and see if there are any shorts in the ECU. I resolved my issue by finding a short in both the wire harness and ECU.