Just got a 1989 Honda Accord LXI Fuel injected. It drives fine when you ease into the gas, but if you feather it a little it gets louder, but does not move, and the RPM gauge doesnt go up as fast as I'd suspect it should. It happens both open and closed loop, so I know it's not a sensor that is only operation in open loop like O2's.

Gas mileage also sucks, best I got on a 250 mile trip was 16MPG all freeway.

So far I've replaced the fuel filter, the fuel injectors (with junkyard ones and new O-rings), spark plugs, plug wires, dizzy cap, rotor, tranny fluid, engine oil and filter, antifreeze (just cuz it looked bad), did a 2 step fuel injection cleaning, gutted the cat (also ran the car w/no exhaust after the y-pipe, throttle responce was better, but power was still not there)

So far I've just replaced normal wear items, hoping it was just neglect that brought the problem. Now since I've replaced most the common wear items, I am sure it's gotta be something else.

My best educated guess is either:

Fuel pump
or
MAP (Manifold Absolute Pressure) Sensor.


Does anyone else have any ideas as to what it may be?

Thanks,

Bobby