Verify O2's?
 

Having an issue getting the O2's to turn on. I have verified everything from end to end and only the PCM is in question at this point. So, can I plug in the original S-10 PCM and then view the live data to see if my 0411 PCM has/is failing?

Same goes for the Knock Sensors.

Right now I only get .445 on both O2's and low voltage codes to the knock sensors. This tripped the check engine light and keeps the truck in closed loop. (poor MPG, missing).

I have replaced the Knock sensors & harness, O2's, with no change. Everything is now indicating a possible faulty PCM.

Thoughts?

What engine/transmission are you running? What calibration in the PCM? Lastly, which oxygen sensors are you running? Early trucks in the 99-02 range two different options for oxygen sensors, they were either isolated grounded or case grounded oxygen sensors. This means the calibration in the tune needs to match the oxygen sensors you are choosing to run as well as the wiring must be correct.

O2's
 

Running the 2002 F-body O2's. F-body manifolds. O2 placement is in the manifold on the dr side and in the Y pipe at the flange area on the pass side. These are stock to a '02 Z/28 with 5.7

Gotcha. Is the tune in the computer for a LS1 F Body? The F Body tunes usually take about 2 minutes to go closed loop before they start trimming out. This is with a stock file.

OK, but this is all the stock 5.3 tune and is not going to closed loop. Verified this last night on a Tech Two scanner (Buddy has one). Starting to think that the voltage reference is off or possibly not happening at all.

I did verify that the is power to the main fuse block at all positions. Need to crawl under and check my plugs to the O2's (moving this week) but that is going to be next week. We are looking for the power reference for the '03 S10 (4.3 w/ 4L60E) and the Silverado (5.3 w/4L60E) to look for the issues that way. Any ideas on that one?

Have to figure out the daily driver (S10) so I can move on to my GS swap.

Ug!
 

Well, still trying to get the shop sorted out & everything put away, but took time on Sunday to replace the ignition switch & multi function switch (also a different gauge cluster). After 5 fun filled hours......no change. No cruise, no gas gauge, no O2's and the knock sensor still trips.

I did fix an annoying leak at the upper radiator hose and got a replacement wiper arm to fix another annoyance. I really don't want to pull out the engine to rerun all of my harness connections/wires.

I did find that the 30 amp mega fuse and a IGN E fuse were burned out. Replaced with the same issues still present.

Any ideas before I go back to stock 4.3 V6?

If your oxygen sensors are from a Camaro and wired to the PCM like a Camaro gets wired, then change the tune to a Camaro and see if you start getting activity. All those three parameters must match in a 99-02 Red/Blue.

Found it!
 

Finally found the issue. Even though I had O2's for a 2002 Z28, they were the wrong ones. I installed an '01 (case grounded) O2 for a 2001 Z28 and the live data shows that it is operational. So now I need to add in a new bung on the drivers side and put the other O2 in.

The codes now show only the Bank 1 (dr side) O2 code and of course the knock sensors. I have a whole list of things it wasn't (pile O' parts too). I still have the IN/OP gas gauge to fix along with the R rear tail light running light. Almost ready to get it tuned.

For the group: Could the non functional gas gauge issue be in the main underhood fuse panel?

Replaced: PRNDL switch, a bad fuse at fuse block, the entire gauge panel, the ignition switch and the multi switch. I also pulled the box and plugged in a new fuel pump. Nothing has caused the gauge to do anything (reads "Low Fuel" and empty on the gauge) Been driving using the trip meter