2000 Accord EX 3.0L 6cyl
220k miles
only check engine light is P0420 code. i changed catalytic inverter and O2 sensors
also has new IAC or EGR valve. due to idle surging. months ago

Car runs great. just moved to florida so ive been using the a/c. when the a/c is on i have multiple issues and they seem to be related:

No Power

1st and 2nd wont shift untill 3500 - 4000rpm

it wont accelerate unless 1/2 or more throttle applied and it hesitates / bogs and rpms wont rise for a few seconds then takes off like a rocket.

and while at cruising speed i can push throttle a lot and car will slowly accelerate and same power even if i let out throttle most of the way. understand? hard to explain. basically if i try to accelerate it doesn't matter if i push throttle a little or a lot i get same amount of acceleration.

and i get about a 1/4 of mpg with a/c on. Literally. i can fill tank half way and get maybe 80 miles. with a/c off i get 180+mpg per half tank

it seems like maybe all these things are related some how. almost like its not getting enough air or fuel. idk

these symptoms only happen when a/c is on. other wise the car runs great.
someone mentioned that maybe its not getting any advance on ignition

thanks for your help.

 

My 97 had a severe lack of power when the A/C was on to the point that I thought it was going to die when idling every so often. I went ahead and changed the plugs, wires, rotor, cap & installed a new Bosch alternator that provides 10 more amps then factory and it no longer has a problem with the drag of the A/C.

 

my initial guess is your ecu is bad, this assumes that the plugs are good

i would probably check for an exhaust leak if the plugs are fouled

 

Thanks for your help. I put new plugs in a couple months ago NGK. The plugs were not fouled. And I do have an exhaust leak in the flex pipe.

you think it's worth changing the alternator and ignition wires?

 

warm the car up, unplug the oxygen sensor connector and see if it runs better when it throws the check engine code for oxygen sensor

 

Which O2 sensor? In engine bay or by catalytic converter?

 

the front one