salmaan

Hi guys,

My last engine f20a (non vtec sohc obd1) was blown and was heating up so i swapped it with a f22b vtec (black tapped cover obd1).

it took me a couple of days to start the car, i used the same wiring which was on f20a and i used it on f22b. i changed the ECU (i dont remember its model no. right now but its the right one which came with my f22b).

the engine fired up quickly ( i havent connected vtec, its solenoid, IAT yet, rest of the sensors are connected) without any issues but idle was surging so i thought its the start and things might smooth up after running it for a while but it didnt.

after running engine for a few hundred kms even then the idle is very bad seems like engine is missing, not smooth, shaking (i took out the plugs and all of them were kind of black so it was running rich) mileage was very bad, power was not there as well. starts idle hunting at time as well, i tried adjusting idle screw, TPS and dizzy timing but nothing helped

please help.

GhostAccord

I am not familiar with the F20A Accords wiring. However, if you have not connected the IAT sensor yet that could be a reason for the rich running condition. The hunting idle can be attributed to an air bubble in the coolant, a vacuum leak or dirty IACV valve. The IAT may have something to do with that as well. i've never driven my car without an IAT so I'm not 100% on how it acts without one.

Is your check engine light on?

salmaan

- my check engine light is not working, may be because CNG was installed on this car/f20a and has not been removed completely. is there a way i can check engine codes thru ecu with a multimeter?
- f20a was OBD1 and so was my f22b vtec so i'm assuming that both will have same wiring, i only had to extend IAC connecter; rest was spot on.

idle problem is possible with non connected IAT? does ecu goes into openloop if its not connected? could you please check?

salmaan

help!!!

i've cleaned up my IAC and connected IAT (now only vtec pressure/vtec sensor) is not connected rest is all ok.

still missing and shaking on idle.

chikin pickle

The ECU pins a6 and a11 are reversed in the ecu connector harness in the accords that motor came out of. If you used an accord ECU then you will need to switch the location of those two pins in the connector. One of them is for the EGR valve, which is probably opening and messing with your idle.

GhostAccord

The other is for the primary O2 sensor heater circuit. Having them mixed up would cause the EGR valve to be open all the time. At idle the EGR should not be open.

salmaan

my existing engine was F20a (SOHC non-VTEC) which came in my Innova (this is a JDM Accord with a different shape)

Now i dont know from which car this F22b came out of but its a VTEC OBD1 engine and the ECU i have is P0A, shall i swap these two wires??

How much HP does this black top F22b SOHC vtec has??

holmesnmanny

http://en.wikipedia.org/wiki/Honda_F_engine

salmaan

ive been thru this wiki page, confusion is that there are many F22b variants available. this engine also came with a silver top with vtec written on it and mine is a black top with vtec written on it, its a jdm motor so no number after f22.

chikin pickle

I'm actually not so sure about non US cars. One way to tell would be to check the EGR valve wire with a multi-meter. If there is constant power there you could be fairly certain.

salmaan

@chikin Pickle

how does EGR works in F22? is it open if not connected? or closed?

GhostAccord

It is a normally closed valve.