Crank sensor is original (to my knowledge).

Yes, IAC appears to be functioning normally. I can see commanded IAC and actual IAC and it tracks right along with it perfectly. TPS also appears to be correct. It goes to 0 when I close the throttle and tracks correctly with throttle input.

 

Following this thread. Same thing 2001 5.2 with same P0132. Done everything you have done. Been Battling for months now trying to get it fix to pass emissions test.

 

Alright, I put yet another O2 sensor in it (this time a Denso) and it fixed the O2 high voltage issue and the idle issue. On my way home today though it threw two codes again, both of them for the heater circuits. One for sensor 1, the other for sensor 2.

I'm thinking somehow there is something faulty with the O2 heaters, and that is what has been killing them so quickly.

Anyone have thoughts on this? I know the O2 heaters are powered on the ASD relay, which obviously is working because the truck runs. I am not 100% sure where to go from here with my diagnostics. I hate electrical.

 

You mentioned that before if IIRC . First, you need to figure out a way to get the fuel trims. FT are standard/required OBD2 data pids so if your SW doesn't show them there's something wrong. What exactly is the OBD2 interface you're using, and what SW ? There's a lot of free or trial/demo applications for all sorts of devices and operating systems so likely there's something else you could use.

Second, verify the heater circuits. Volt meter or test light will work. Dark green/white **at the harness side** (wires between the sensor and connector are different color) is power from the ASD relay. Brown/violet (upstream) and brown/white (downstream) are the PCM controlled grounds. The easiest way is to disconnect the sensor and test at the harness side plug. The FSM has the connector pinouts if you're unsure which wire goes where.

Don't go down the "fuel sync" rat hole (yet), 2001 isn't as picky about it as the '96 that true blue has.

 

Very true! I've herd many times that fuel sync was only required for starting after the '96 year model. Mine, on the other hand, needs that cam signal just to run so it seems.

 

Certainly true for 98 and newer, I started a thread about that a while ago https://dodgeforum.com/forum/2nd-gen...overrated.html . 23:45 into the video the guy actually disconnects the cam sensor on a running engine and it keeps running. Even on older ones it's not timing anything, just letting the PCM know which cylinders are coming up for fuel delivery.

 

Yeah, I found that out the hard way about 20 years back, lol! Twas one of those....oh yeah?!? moments.

 

Update: I might have accidentally stumbled onto the issue while troubleshooting my AC clutch. I ended up having a ground wire that was almost all the way broken off, making intermittent contact. While reading through the wiring diagrams in the service manual, I believe that same ground may handle the O2 sensors (service manual says it does on some models). After fixing the ground (which fixed my AC clutch issue) I took a drive and watched the live data for the short/long term fuel trims, as well as the O2 sensor. The O2 sensor seemed much more lively than normal, and the fuel trims were closer to baseline. Before, the short term fuel trims would jump around quite a bit in the negative (trying to pull fuel to correct a fat condition), sometimes more than 10%. Long term fuel trims were also usually in the -10% area. During this drive though they were very tight, short terms were usually between 0 and negative 5%, and long terms typically stayed between 0 and negative 2 under most driving conditions.

We shall see in the coming weeks if my issue returns, but I am hopeful that this was the fix.

 

Please update bc I’m still having the high voltage issue. I am truly lost.

 

Ong they needa spill the secrets i have a 03 3.9 and replaced intake and sensors but still backfires and idles rough randomly randomly.