Jay, Here is my 2 cent, Start with easy stuff. I will start with the fuel pressure guage to determine the fuel pressure in fule lines. Do that when the truck has been sitting for a while to see if fuel get drain back to the tank while its not running and also then start the truck and check the fuel pressure in line. I don't have PSI pressure number on hand but you may be able to find on FTE or google.

I have the issue with my pontiac and i have 02 sensor running rich or low and I went after codes, nothing but waste of money. Try to pinpoint the trouble. As far as i understood, O2 sensor just work fine but other sensor such MAP or other sensor giving bad reading to main computer and computer is giving fuel on base of those readings.

I am not an expert and new here too, but this what i have learned going after codes.

Jamal

 

koeo you should have 50 psi however you won't be able to check it with a gauge

Jamal, you always use the codes you just have to know how to interperate the codes correctly, you also have to know what the different parts of the engine management system does, so telling some one to not go after the codes is wrong, sounds like you have been at autozone where they( most) don't know better and sell you what ever part is mentioned in a code, also you said you have an o2 sensor running rich, maybe you wrote that wrong, but they don't "run" rich they monitor that the engine is running rich

 

Update:

Pulled the injectors like fordtech08 described. No leaks in bank 2. After I put it back together, I pulled the vacuum hose on the fuel pressure regulator (while it was running) to check that. Nothing. Looks like it has a sensor on it anyway.

More interesting info: I've driven it a little bit over the past two days and it has been starting fine. Even after sitting over night. Also, the idle is not nearly as rough as it used to be. It's running low on gas. I'm not sure if that has anything to do with anything.

The ECM reset after Autozone read it and the CEL came back on, even though it's starting and running better. I didn't get those codes checked, but I'm assuming they were similar. The ECM has since reset again after pulling the injectors.

Now, I'm thinking... coils? I don't know. haha

pdq, could you explain this a little more, please?

 

No, the CEL is not flashing. For the misfire counts I'd get something like, #1-75, #3-255, #5-25, and 2,4,6 will be zero. #3 is always the worst.

It's a distributor system with a single coil. New coil, cap, rotor, pick-up coil, fuel injectors, crank sensor, and on and on.

I replaced the intake/throttle body/plenum gaskets and nothing changed. Vacuum reading is rock solid. A compression test had all cylinders up around 180 PSI and all were within 10% of each other. This one has had me banging my head against the wall for a long time.

 

If it helps smooth things over, my Fords owned outnumber my Dodges 2 to 1.

 

have you checked to see if there is trash in the fuel line on that side?

 

well you could go get your codes again make sure it is still missing on number 6 then swap coils 5&6 if the miss moves to 5 then you have a bad coil

 

Glad to hear that, you had me worried there for a while. Personally, for me anyway, the thought of myself owning a Dodge makes me want to

 

I took the entire fuel rail off when I changed the injectors. I ran cleaner inside of it, drained it, and blew it dry inside and out with compressed air.

 

Hold it! If you pulled the vacuum hose off the fuel pressure regulator while it was running and nothing changed, I think your digging near the patatoes!!

The fuel pressure regulator (FPR) is exposed to a higher vacuum when under light load (as when the engine is just idleing). WHen the engine is under load (as in when you blip the throttle) the vacuum drops significantly.

(Note; I refer to it as vacuum (cause I'm an old carb guy), but the engineers refer to it as pressure. So when the vacuum is high the pressure in the intake is relatively low. Conversely, when the vacuum is low (when you blip the throttle or put the engine under a load) the pressure in the intake increases (i.e, approaches atmospheric pressure).

The PCM is pretty smart. When it see the vacuum decrease (I mean when it sees the pressure in the intake manifold increase), it knows the fuel injectors won't squirt as much fuel into a high pressure as it will in a low pressure manifold, so it bumps up the fuel pressure to compensate.

I'd sure like to see a fuel pressure gauge check your fuel pressure with the vacuum line connected and disconnected. Your fuel pressure might just be running high all the time. (And if the diaphram in the FPR is ruptured it could be leaking fuel into the vacuum line which may be loading up a cylinder near the vacuum connection. (I say "may be" because I'm not familiar with the 2006s - they may have the returnless fuel pump system instead of the version with a return line, or if they have both a FPR and a fuel rail pressure sensor.)

 

The EVAP canister holds fuel vapors from the fuel tank in a charcoal medium. Under certain condictions (i.e, when the all-knowing PCM decides that dumping the fuel vapors into the intake will not cause a driveability issue), the PCM will activate the EVAP canister purge valve and the gaseous fuel will get sucked into the intake. If the EVAP canister purge valve doesn't shut all the way (for what ever reason) it could allow extra fuel to get into the intake when it shouldn't. (See P0172 and P0175)

 

Good call because it would also explain fuel pressure bleeding off when the engine was not running.

 

I'm guessing that includes new wires. I do know that the Mopar 360 is very fussy about how you route the spark plug wires to prevent inducing a spark in an adjacent wire if they run parallel and close to each other.

 

the truck does have a fuel rail pulse dampner so if you remove the vac from it nothing would happen, it's not a pressure regulator

 

the fuel pressure is regulated by the speed of the pump controlled by the pcm reading the fuel rail pressure temp sensor