87GMC

Used the search button and found some information on these codes but didnt find what exactly was happening to me.

Car is throwing the codes so I decided to autotap it and found when idling the car has no misfire once you give it gas misfire begins to show on autotap. You can hear the car missing when just idling but the computer is not reporting at idle. The car feels like its running on 7 cylinders and the miss seems to get worse as the car warms up. Also o2's look all out of wack specially on bank2. LTFT on bank 2 are like -10 at idle and bank 1 is +1 at idle. I have noticed before at idle you could feel like a slight miss but the car had always ran good never missed.

An opinions on if its the coil or............. It just seems to get worse as car warms up. When cold it misses but not as bad

txhorns281

iTrader: (12)

P0307 = Cylinder #7 if I'm not mistaken

O2 sensor
Injector
Plug/Wire
Coil Pack
Broken Spring
Pushrod

Some things to look for on cyl 7...

87GMC

it is cyl 7 from what autotap tells me. The only reason i question it is the way it acts. When its cold not as bad as it warms it gets worse.


Also which is cyl 7? Is it still considered 1357driver and 2468pass?

2001NBMZ28

Yes, #7 is the rear driver's side. Go for the plug and/or bad wire first.

87GMC

Also on the O2's which one is bank1 and bank2 meaning driver side and pass?

2001NBMZ28

Bank 1 is driver's side, Bank 2 is passenger side. Sensor 1 is pre-cat, Sensor 2 is post-cat.

87GMC

misfire on driver side and bad o2 on pass side. Man i need to get to tuning up the car.

Thanks for the info guys

87GMC

Ok checked the number 7 cyl (rear driver side) I have spark and everything looks good.

At idle its hard to notice that it is missing, you can hear it a little but thats about it. Also its not that bad when cold but as it warms is when it gets a little worse and starts throwing the p0300 and p0307 code.

I know it could be a pushrod or a broke spring but wouldnt the miss be constent? I have had a broke valve before in my 350 chevy truck and it miss ten times worse than the car is doing now.

Is it possible a bad injector or dirty one? Looking at my short term trim at idle the driver side is showing way lean like 8+ and passanger side is showing way rich -10. I figured if the passenger side is showing way lean thats the side the code is telling of cyl #7 could it be a bad injector or dirty thats why it get worse as the engine warms?

87GMC

If I disconnect the spark plug wire and let the engine run for a few min will the injectors still spary fuel? I'm of thinking of doing this to see if the injector is putting fuel into the cylinder. If the plug is wet i'll know the injector is getting fuel in there and its something else.