Will it zip out to well over 80 on a flat road?
Its going too fast to be vacuum IMHO. I assume your TPS is unplugged, Throttle Position Sensor.
Curious to see what happens tomorrow. I don't think its the wires or the plugs or it would fall down on acceleration in lower gears at lower speeds when droning down the road in 3rd or 4th gear.
Sounds more like Throttle position vs. RPMs.
My first suspect is ignition coil if its parts related. But that is just a guess with absolutely no foundation.
Curious to know how if performs flat out and well over 70 under stress in 5th gear.
