Engine Miss @ Idle

[Tom Honeyford]

I cannot cure a "miss" @ idle. 119,000 mi. on odometer. I changed plugs, wires, and coil pack. Tried premium gas, and injector cleaner (2x). It only misses at idle. OBDII reads cyl.4 misfire. If I clear reader it seems better for a few days but then returns Could I have one bad fuel injector? Oh, 2002 gen 1 Trac. I love it and will keep it forever!

 

[Yardsale]

What is the code?

 

[Tom Honeyford]

304

 

[Yardsale]

See link below.



"A code P0304 may mean that one or more of the following has happened:



Faulty spark plug or wire

Faulty coil (pack)

Faulty oxygen sensor(s)

Faulty fuel injector

Burned exhaust valve

Faulty catalytic converter(s)

Running out of fuel

Poor compression

Defective computer"

 

[Tom Honeyford]

I rule out plugs, wires, coil pack,Compression,fuel shortage, & burned valve. Not looking forward to changing injectors. Computer tests OK.

 

[Dreman]

Fuel filter? Fuel pressure? Just thinking out loud...:banghead: