Hi guys

So a little backstory to this, had a 1998 honda civic ex d16y8 donor car. I basically stripped the whole car down. bought a 97 shell and gutted it.
I installed everything from the 98 into the civic. Motor, wire harnesses ( engine, dash and floor ), Fuel tank pressure sensor and charcoal filter which is important for the context. basically converting everything to ex.. power doors and windows..all that jazz

The car has always started up fine and idles since the swap but here is where things go off.

• First drive - Check engine 30 miles into drive got cel P0450 (evaporative emissions control system pressure sensor)

At the time I hadn't installed a dash harness just the floor and engine, I found a guide that the hatches didn't have a fuel tank pressure sensor as they had a different engine. so I went to the junkyard and pulled a unit off of another 98 ex model and installed it and cel goes away

• Second drive - drives about 75 miles and pops a cel which hadn't shown up the first round p1456 ( Fuel tank temperature sensor circuit malfunction - EVAP control system)

searching around this time and I find the check gas cap which mine was pretty worn down so I got a brand new OEM cap from honda, I reset ecu again.

• Third drive - I drive 130 miles this time before cel p1456

At this point I am running out of ideas, I have basically converted the engine car to a ex at this point just shy of changing out the gas tank but everything on the tank seems exactly like the ex from what I can tell. maybe a leak in the filler neck? the car does smell feint of gas but not as much as it did before I added the ftp sensor

Any ideas?

 

What was the donor car for the ECU that is currently installed in the 97 Civic?

 

it's the ex ecu

 

Were EVAP codes also thrown in the donor EX?

 

nope, car ran perfect. no codes, always idled smooth. I neglected to take the ftp sensor out of the donor and ended up with a junkyard one. it looked in decent shape

 

 

I have checked most all of those. The only one is the shut valve as I don't have a pressure tester