Hi,
The idea that the tachometer drops to 0 while driving is what makes me think it could be related to a crankshaft position sensor. As far as the low power, it could be several things such as a plugged or partially catalytic converter, a fuel pressure issue, and so on. However, those wouldn't cause the tach to drop.
Certainly, check the transmission fluid. If it is low, it could allow the transmission to slip which would make it slower to accelerate.
Let me know.
Joe
Thursday, June 23rd, 2022 AT 8:17 PM