My sandwich needs a little stone ground mustard… and a dash of pepper, lol. I fully expected to see a couple pounds of BP but don’t, at idle the needle jumps around a lot from way negative to 1 1/4 but settles lower and at 2500 rpm I don’t see any BP at all? Somethings up the live data chart for O2 bank2/2 is wack could this bring be back to it being poisoned by the coolant and oil from the cooling system?
Reoccurring P0306 on 2006 TJ 4.0 stroker
- Thread starter 1515art
- Start date
Cat looks good. That answers that question. You say the Bank 2 sensor 2 data looks wack, but you don't show what you mean? All you have that I see for Bank 2 is Long Term Fuel Trim which is still reading crazy rich. Again, I only understand how this system works unmodified. Idk what happens after someone throws huge injectors, tunes, and strokes it, but that doesn't seem right to me at all.
The fuel trim is off I think because the bank2/1 sensor is hanging outside the exhaust by its wiring reading fresh air?
So I ran some tests these first 3 screens are at 40 mph up a slight grade with Cruze in control
This next screen after at idle
These next screen is an overlay bank 1 and 2 sensors 1 at 40 mph up hill cruse control
Fuel trims before a 40 mph run, during and after
Before
During
after
So I ran some tests these first 3 screens are at 40 mph up a slight grade with Cruze in control
This next screen after at idle
These next screen is an overlay bank 1 and 2 sensors 1 at 40 mph up hill cruse control
Fuel trims before a 40 mph run, during and after
Before
During
after
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Now after looking at the live o2 data I’m not sure the bank 2/2 sensor looks all that different from bank one, there is a spike in the chart at idle I’m not really sure what caused it but it looks equal on both banks?
Something forced a quick rich condition. But those readings look perfect post cat.
Thanks a lot for the help, I don’t know I can’t really find anything wrong and it is running good? I drove it probably 40 miles today around town and freeway with no check engine light, I haven’t checked to see if anything’s pending yet. I got on it and getting on the freeway opened it up WOT until the PCM switched to see what the numbers dropped too, when it switched it went rich at 13.3/1. When I had the untuned PCM and larger injectors it would drop at first to around the same value then continue to get richer as much as 9.x/1 towing my Aliner up a grade. I guess the 13/1 is safe if it wasn’t I’d get a code pretty quick I think and probably flashing too.
for now I’m just going to have to drive it and see if whatever was/is going on comes back and then see what I get to work with, if I’m lucky the light burned out, lol.
Whatever of all the things done to track down my p0306 and other occasional DTC’s I’m now 500 miles check engine light free.
Taking a guess I’d say the main contributor to making things right was slightly smaller oversized injectors and the mild tune on the PCM, going back to my old stock factory OPDA sensor is also still best.
Knock on wood it’s running best it has so far.
Taking a guess I’d say the main contributor to making things right was slightly smaller oversized injectors and the mild tune on the PCM, going back to my old stock factory OPDA sensor is also still best.
Knock on wood it’s running best it has so far.