Hi guys,

I need help.
I just put a 97 B18B motor & ecu into a 97 civic cx.
i used the stock civic harness,
did the iacv fix &
wired in the different plugs correctly (alternator, crank fluctuation sensor ect.).
The motor runs strong but,
i'm getting code 91 which is tank pressure.
I'm lost & have no idea what to do.
I've done my research &
never heard about any other changes that need to be done to the wiring other than what i mentioned earlier.

Does anyone have any ideas?

Thanks,
JAY.

 

Gotta love code "91" The fix is to get an 96-00 EX gas tank with the pressure sensor in it(you could probably get the sensor and weld it in, but I do not know how reliable it would be, plus welding a gas tank . Next think is to get the charcol canister with the purge soliniod on it. Wire it all to the ecu and you should never have the code again. I have also heard 96 ecus did not have code "91". Another way to get rid of the code is to go OBD1.

 

OR the easier "work around" is to turn the key to the accessory position (don't start the car) and count to 10. Then start the car.

That lets the fuel pump pressurize the system and the code won't come on.

I only got the code when I ran a USDM ECU and the car sat for long periods of time like overnight.

 

I always let the fuel pump prime and still get the code.