davidpaustin

I know this might have been covered somewhere, but I've been searching for days and cannot find a real answer.


Basically, my car seems to run great, but will throw a code 43 only when going downhill in gear. I realize the car actually will stop sending fuel while coasting in gear and I believe this is why I am receiving this code.


Is there any solution that anybody can think of, so I don't have this error code anymore.


The engine is fully rebuilt, D16A6 Block, Y8 head. New Wire Harness, New P28 ECU, Just cleaned IACV and FITV. o2 sensor has been replaced more than once recently. New Fuel pump, and filter. Checked injectors and flow seems good and steady. New Dizzy. It's the only code I get and only when going downhill in gear.


Even if someone can send me a link to another thread that this has been covered under, I would really appreciate the help.

Star1967

What type/octane of fuel are you using and from where? Such as Amaco/BP. Have you cleaned or replaced the gas tank?

davidpaustin

Thank you for the quick response. I live in Hawaii and tend to fill up at the Aloha gas station and use the highest octane available. I believe it is 91 octane. I figured with a newly rebuilt engine the higher octane would help.

Star1967

Your welcome. The 91 octane will help. I run 92 at BP in Missouri, I have 2001 Civic 4 door just had the valve cover/cam sealed and plugs replaced. An old gas tank could have varnish ,dirt ,rust ,and other junk over the years caused by bad fuel , sitting still for an extended time , or just plan neglict. Are you the first owner of he or she?Have you tried a gas cleaner like Lucas Injector Cleaner or STP.

davidpaustin

Sorry. I did that last post a little too quickly. I should have mentioned a few months ago I drained my gas tank and replaced the fuel filter and fuel pump, because I thought it might help this issue. I filled up my gas tank again today and it is actually 92 octane.

Star1967

It's okay. Did you check the floats in the tank? If not watch your gas gauge when it's under a full tank that will tell you if something isn't right. It also could be vapor lock if the temps are high. It happens here when you have quick warm-ups after cold weather.

davidpaustin

The floats seem to be pretty normal, but is there a way to test the vapor lock and as a thought could it be that I have a FITV unit from the original engine (auto trans) and should convert the FITV to a unit from a manual trans (considering I have done a manual trans swap. Maybe the sensor has minor differences.

Star1967

I didn't think of that but you could be right. What kind of gearing is in the transmission? Since you mentioned you are using a manual transmission the computer might be reading a false rpm giving it the command to the fuel delivery system you are standing still. On some engines the car turns off when at a stop sign and restarts when the pedal is pressed.

davidpaustin

It is a Trans from a D16Y8 1996 Ex model, but it matches the head and the P28 ECU should do the trick... Although the computer might be having issues, considering I sometimes have to reset it after using the AC. Is there a better computer for that setup?

Star1967

I was wondering did you change anything on the engine itself? Might need to get the manual Y8 intake manifold( something about the ECU on the automatics when you do the change) and the chip set or comp out of a manual donor car. I wish I could help you more.

davidpaustin

I actually have a skunk2 intake manifold, but it has the throttle body from the automatic, which means the sensors are from the automatic, so I think that may actually be the problem.


Thank you for all the help.

Star1967

Your welcome and good luck.