So, the first trip of the day and only the first trip, when accelerating past 55 and before 60mph, the engine will sort of studder, then the speedometer will start to fall to 0, the gas pedal doesn't make the engine rev, and the two "fixes" I've found are, 1) rapidly hitting the gas pedal, but that only gives me a few seconds of power, and 2) putting the car in neutral (while still moving) turning the car off and back on then putting it back into drive. I've only had to do #2 more than once a few times to get it to work again. After that, let's say I make a 2 minute drive, park, get lunch, get back in and drive away, it doesn't have an issue. Even for the rest of that day. It doesn't matter if it sits for just a minute or hours, after the first trip, it's fine.
I've tried cleaning the throttle body, it had very little carbon build up, and it seemed to move just fine. Outside of that, I have no ideas.. it's an automatic, been well maintained for the most part. But because of the weird way it acts, because sometimes it doesn't do it (rarely), and of course it won't do it for a mechanic. It has good transmission fluid, good on oil..
It does have a light on, O2 heater circuit malfunction bank 1 sensor 2, O2 circuit no activity detected, HO2S circuit high voltage bank 1 sensor 2, HO2S heater control circuit bank 1 sensor 2. I've replaced both O2 sensors and didn't fix the issue(s). And it doesn't seem to bother the car after the first trip anyway. I did have to replace the header w/ catalytic converter, because the car had a code saying it was bad. But then these new issues came up. I've also replaced the TPS.
Over the years it's had a new ecu or two. Another weird thing, I don't think is related, is the digit clock on the dashboard never is correct, and seems to randomly forget what time it is and resets itself.
My theories are possible clutch/transmission issue, the TPS is bad or going bad, maybe a fuel system problem, and there is a broken wire somewhere (for the sensor issues)
I know that's a lengthy post, with more than one issue. But I'm more concerned about the weird loss of power than the sensor. But if anyone can help with one or both, I'd be extremely grateful!