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About LinkBacksThank you, I'll definitely give that a shot when I get home. Can you think of what would cause alll the random numbers (timing, throttle, load %, etc) when I'm watching the live data?
Thank you, I'll definitely give that a shot when I get home. Can you think of what would cause alll the random numbers (timing, throttle, load %, etc) when I'm watching the live data?
The only thing I know for certain is that -40 from the ECT is the default/open loop number, so it's also possible the ECM won't or can't go into closed loop for some reason. Perhaps the problem is when it's trying to close the loop. Pure speculation on my part there, but your case is just so unusual, with it running well for a short time, that it causes my to think about all sorts of weird possibilities.
And here's another test you can try. If disconnecting the O2 sensor doesn't change anything, then disconnect the battery overnight. That will clear the ECM of all learned data, and the next startup will have a clean slate. Or maybe you had it disconnected for a long time anyway, during all of the part replacement work that you just did?
I did have it disconnected for about 4 hours two to three times now.
I tried with the O2 unplugged and it did not make a difference. I have unplugged the battery now with the O2 sensor and was going to let it sit tonight before trying again tomorrow. I did take a quick video of it starting and then dying (no throttle or anything) if posting it would help?
NOTE: the air box is off for diagnostics hence the reason it sounds a bit throaty.
I'm going to put that temporary performance improvement on the shelf, and will just suggest standard diagnostic testing for the symptoms that your vehicle currently has. So if you're still willing to continue this process, then I'll suggest testing the TPS, but that will require back probing the connector to check it with a multi meter. Are you familiar with back probe testing of connectors, or do you have wire piercing multimeter probes?
I am definitely willing to continue. I do have a multimeter and familiarity back probing. I am not certain where the TPS should be or the standard values I should get.
Unfortunately the free source I use for wiring diagrams of vehicles that I don't own is erratic and hit-or-miss. And in this case it's not showing a diagram for the TPS with actuator. And I searched elsewhere, with no luck either. So without the pinout of the connector, it would be fairly time consuming to try figuring out what each pin does. And then there's the APS that comes into play with the drive-by-wire setup as well.
The TPS can't be replaced on these, so the entire throttle body would need to be replaced. I can't in any way suggest replacing the TB and the APS pedal assembly, because that's just throwing darts. The TPS normally sets a code when it goes bad, so that's a big factor in favor of not hanging on a new TB. Although it's true that the TPS and APS are in the ballpark for the symptoms you're getting, there's been nothing yet to strongly indicate that either one of them is bad. It would be helpful to find that TPS and APS wiring diagram, in order to do some testing. Alldata and Mitchell have them, but it costs $$ to subscribe those.
There is one other thing I want to mention related to your compression testing. My compression readings were quite a bit higher - all right around 200 PSI. One thing I suggest is to repeat that test and see if the results are actually around 150. If they are, I'd want to find another compression tester to see if perhaps your gauge is not reading correctly. IMO compression around 150 would likely indicate a timing belt loop issue. Timing is a bit of a PITA to check, because you have to remove the harmonic balancer in order to get the timing cover off to be able to see the crank pulley mark. Unfortunately this starts to get into the non-simple area now.
Do you think it is possible that the belt skipped a tooth on the crank end? I have verified the cam gear marks line up. If that happened, would it explain all symptoms? I ask because I know I have a seal leaking a bit and it appears to have gotten on the crank gear which could make belt slick
Well I just took the rim/tire and pulley off and verified timing has not skipped a tooth or anything...I am not sure it matters but the day before it stalled for the first time was the day I replaced the cam position sensor. It was a genuine GM part and eliminated the code it was throwing for bad CPS. I have since replaced it again to verify I didn't get a faulty sensor.
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