2002 Infiniti Q45 • 230,000 miles

I have just bought this Q45. It runs great on the fwy. However, acceleration from a start is not smooth. I have a smell of fuel or exhaust from the manifold area. I have a scanner and pulled 3 engine codes.

Here's the codes:

1. P0306 - Cylinder 6 Misfire Detected ( could it be a coil or fouled plug? )

2. P0330 - Sensor 2 Ckt Malfunction Bank 2 ( what should I do? Replace the knock sensor? What is the term "Ckt"? )

3. P0505 - Idle Control System Malfunction ( Should I inspect and clean the throttle body with a spray? )

Thanks in advance.

December 24, 2012.

Do you have a constant miss fire at idle?

Dec 24, 2012.
I would try cleaning the idle air control valve. But let's hold off on the knock code till we fix the miss fire code code be setting the knock code.

Dec 24, 2012.
1. Yes also injector pull plug take a look maybe fouled
2. Maybe open or short in circuit[CKT] or knock sensor
3. Either faulty throttle actuator or intake leak
Would start with plug inspect then erase codes drive see what resets

Dec 24, 2012.
Here's an update: Today I took off my intake and cleaned my "MAF SENSOR" with CRC maf cleaner.

Also, I bought "sea foam" throttle body cleaner and sprayed and wiped the throttle plate.

I cleared the codes and test drove it.

CEL came back on again. This time one 1 code though. It was "P0505" Idle control malfunction. ( IAC VALVE. Should I replace it? )

Dec 25, 2012.
The first thing you need to do is see if you have a vaccuum leak?

Dec 25, 2012.