At cruising speeds on the freeway around 60-75mph the car hesitates then i have to step on the gas to stop the hesitatating. the hatch has a 1 gen B16A with stock computer. Ever since I did the swap the idle flucuates sometimes its at 1200 RPM and sometimes it will idle at 700 RPM pls help me with this problem

 

bump

 

i kinda had the same problem when u did the swap did u change the fuel relay plug?

 

no I didnt let me try that. could it be my fuel pump isnt flowing enough?

 

hey i have a b16 1st gen engine too. i had the same problem with the idling. It was my fast idle thermo valve. There is two holes in the throttle body before the butterfly valve. When the car is warmed up check to see if the bottom hole is sucking in air.. If it is its your fast idle thermo valve. Plug the bottom hole and it should idle fine. Next step is to take off your fitv and take off the plate, there is two screws to take off the plate. use a socket not a screwdriver. Then there is a white piece inside that you screw back into place. You shoud screw it in all the way then screw it out 3 or 4 turns for the perfect idle.

next problem is the bogging on the highway. what gas are you using in your b16. it should be supreme or high octane. if you are using regular gas then there might not be enough octane for compression and thats why it boggs. try it out. those are the exact two problems i had with my b16.

 

fuel pump....get a walbro 255lph

 

How did you wire your two O2 sensors? Could be they are backwards at the ECU. Also on your idle check a few things:

1. Throttle cable tension for sticking
2. Clean out the inside of the throttle body where the butterfly touches it
3. Remove your IACV (back of intake manifold) and clean out the screen
4. Take off the FIV (underneath throttle body) and screw in the white plunger
5. Check and make sure you have no air in the coolant system