I have a 2000 h22a4 hooked up to a 96 ecu (OBD2/no immobilizer). After a little bit of driving, the ecu throws a code saying that I'm running rich. When I reset the ecu, the CEL is off until another bit a driving, same code. Also, when I idle, after maybe about 15 seconds, the idle very slightly jumps up and down, and then finally drops to just a tad bit lower rpm idle. On warmer days, the engine dies.

Since the ecu is from the 4th gen with 1992-96 Prelude VTEC Peak and hold 345cc injectors and the engine has the 5th gen 1997-up Prelude VTEC Saturated 280cc injectors, could this be the reason I'm running rich? Am I losing power this way? I do know from reading a lot on here that DOHC engines are setup to run a little more rich than usual, but then I don't know that much about fuel injectors, so this is why I'm asking. Any help is appreciated (except for telling me to search, which I did already). Thanks.

 

ya,your suppose to use the injector from the 96 ecu, that's your problem.

 

92-96 prelude vtec injectors are 345 cc@43psi BUT as used in the h22 they are at 36-38 psi typically which puts them at 310-320cc.
the 97-01 injectors are 290cc@43psi BUT as used in that engine they are at 47-50 psi which puts their in use flow rate at 310-320cc.

 

So basically they flow at the same rate? I wonder what's causing me to run rich then...I've searched around and some people say maybe a bad o2 sensor but then other people say it's not..?

Thanks again for the ecu!

 

somestimes poorly adjsuted valves can cause that code to pop up.

I am glad you could use the ecu, i still get emails and pms about it from time to time lol