I have a Cobalt SS & a couple years ago I had an accident & I hit an embankment on the front of the car at about 35mph. The motor tagged the hood of the car, as there was a slight dent on the hood. Anyway the car drove fine for about 3 months after the accident. Then I started noticing at around 60-65, up mild hills, it was pulsating the power output, even though I wasn't changing throttle position. I also thought it was happening when the weather was warmer. This problem comes & goes. I use to use cruise control, but now the problem happens majority of the time at highway speeds & cruise control & the problem fight each other. Now it is cooler in the mid-west & it is doing it in the cold. When the problem happens, another problem happens at least some to the time, I don't know if all the time, when going up an hill pulsating & the hill levels off to not quite flat, the turbo keeps pulling, like the throttle didn't close back to desired position, I'll have 3-5psi. I let off the gas & give it the gas again to maintain speed & the boost problem doesn't happen again, but I can reproduce the problem easily once it starts doing it. Maybe a couple times a month it starts missing a few times & goes back to normal. It does this pulling out of a stop sign or when the pulsate is bad, when going down the highway.
Also, don't know if it is related, sometimes when I get in to start the car, it won't idle back down after initial warmup routine. I shut the key off then back on, it then idles like it should.
I get P236 "Turbocharger/Supercharger boost sensor a circuit range/performance" error almost daily now. I have tried to disable the error code, but it keeps coming back, but I don't get an engine light, just seems to go to reduced power mode, it still has majority of the power, except low RPMS.
Things I've tried:
Replace ECU, both stage MAP sensors, both o2 & the throttle body.
Verified the battery, main engine & main body grounds.
Today I checked the wiring from the ECU to the throttle body with a light bulb & I wiggled the wires, to see if the light goes dim.
Any ideas on what I should do? I see the absolute load (SAE) pulsating, but I don't know if this is desired load or actual load? Battery voltage seems stable. But maybe I'm recording the wrong parameters. I've tried a performance shop & a dealership, both came back saying they didn't see the problem, but I took it to them when the problem started happening. I attached some logs of the problem.
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