If it was 12 I think it would fry the pcm. I know it it gets grounded everything stops working. If you have a meter you can tap the return wire and see what you have. The normal readings should be in the service manual. How many 02's do you have total? It's not CA truck or heavy duty is it? Pcm ever get changed?

 

There are two (2) O2 sensors, both upstream of the cats, the truck has the heavy duty emission cycle (HDC) and not CA. I hope this info helps.

 

I will have to measure the voltage with a multimeter. The obd2 reader is being difficult and not allowing live data. I will post an update when I get a reading.

 

I changed the O2 sensors again and reset the ECU. The codes are no longer present and truck runs better, but there is still a lack of power. The air filter is clean, the spark plugs are new and gapped properly (.045”) and new fuel pump. I am unable to run any real time diagnostics, but I don’t think there is a misfire/dead cylinder. Are there any good ECU flashes/programs out there?

 

Is it just a perceived lack of power? Anything else going on? Might try a backpressure test on the exhaust. Maybe the cats have melted some...

 

The exhaust is modified to a degree that the cats would no longer be any point worth considering.

Now, I don’t expect any “rip your head back” or even any face melting power, but it is a V-10…I’d expect a more power than what I’m experiencing. It’s a very mild power curve as it is.

 

My V-10 will sit you right back in the seat, and keep you there, so long as you hold down the go-pedal...... If will spin the tires in first without effort, and continue on into second, I haven't pushed that into third gear yet though..... However, I have 33" tires, and 4.56 gears...... so I have a distinct gearing advantage over stock... If you have larger tires, and still the 3.55 gears, that will make it feel like a dog....

 

Yeah, I got 32” tires and stock gearing. I can spin the tires without much effort through second gear, but after that it feels like it lost all its gusto…just all around low power.

 

Reset the PCM, let it re-learn how to run the engine.... See if anything improves.

 

I did a reset about a week ago and drive it everyday. It’s still acting the same. Could it be a crank or cam position sensor?