Scenario/blame matters little because your truck is not fixed.
What is Current status? Is the -8.2 current with no p1345? Which APP are you using? Torque Pro? There are a few threads in engine drivetrain about changing a factor in Torque to get a more reliable number. Test also "usually" done 1000-1500 RPM steady. Tighten Distributor.
As it stands you need to make clear what has been done and in what order...All in one place..... So no new distributor....Just a cap and rotor..... Was coil changed? ICM? Delco/Delphi/GM parts? Ground wire to firewall working? Does the P1351 code still pop? See post 26 and 27 again.
I don't care about blame - I'm trying to figure out if it's even possible that the guy had it set at 0 and by the time I checked it after a short drive it was at -8 (it read -13 when I took it in).
So let's take it from the top...
Rainy day, truck would not start - no spark (verified).
Next day, dry, started up. I've read that some of the ignition stuff on these can start to cause issues over time, so I took it in to a local mechanic that I've been using for years. He said it was the distributor, I told him to change the ignition coil and ICM also. At this point, he changed the cap, rotor, spark plug wires, ignition coil, and ICM. I don't know what brand the cap & rotor are but the rest are autozone duralast I'm told.
This is when I start getting P1351. Start it, stalls after a second, starts next time, runs fine. Most times it starts with no issue, but every time it does one of these 1 second stalls, it throws P1351. I take him an AC Delco ICM and we swap it out, but this doesn't change anything.
At this point, I get a recommendation from this board for the BAFX OBD plug in (
https://www.amazon.com/gp/product/B005NLQAHS) and I'm using DashCommand with it. That's where I got the cam retard readings from and it tells me that it's at -13.
I take it back to the mechanic and tell him it looks like the cam retard is off. This time he replaced the entire distributor, which apparently is from Autozone but keeps the new cap/rotor he originally did the replacement with (I don't know why - the first cap/rotor were higher quality supposedly?) He tells me that now he's getting a P1345 and he's going to set the timing but that that he's not getting P1351 anymore.
I pick it up and he's resolved the P1345 and he shows me it starts normally multiple times, tells me he set it "right at 0 degrees", and shows me there are no codes. I drive home, grab said OBD reader and pop it in. Try to start the truck and get the insta-stall, followed by normal startup. Using DashCommand I see the P1351 code again and the offset at -8 degrees (but no P1345)
I'm tired of taking it back and forth to this guy, despite the fact that I like him and he's done good work in the past. So I'm wondering if maybe I should dive in and try to make the adjustment myself (presuming the correct hold down is there) or if there is some weird scenario where the offset would change by 8 degrees after a short drive.