new motor installed, problems w/ misfiring........
 

OK so i got a '99 d16y7 in my '96 EX. using the '96 EX ECU because I have to change the IAC pinouts or maybe the intake air temp pinouts for the DX ecu to even keep the car running (i think). anyway, I have the d16y8 wiring harness and intake manifold on the d16y7 as well.

the thing misfires really bad if i press the throttle down more than just a little, but at less than i guess 15% throttle pressure it runs just fine. makes me think that the fuel maps on the EX ecu are wrong for the DX motor....but i cannot be sure. i set the timing, lined up perfectly as far as i could tell. tried 93 octane gas- helped a little but not much.

where should i start? do i need to change the ecu to fix this? i don't know if the EX ecu's fuel maps are different or what???

thanks,
andrew

Re: new motor installed, problems w/ misfiring........ (tuner419)
 

start with the throttle positon sensor and distrinutor cap/rotor... then work from there

Re: new motor installed, problems w/ misfiring........ (tuner419)
 

So lets see: Your using a Y8 ECU with a Y7 manifold/throttle body which uses a 3-wire style IACV, but the Y8 ECU is expecting to control a 2-wire style IACV. https://honda-tech.com/forums/images...s/emhammer.gif

CEL on at all?

yeah the CEL is on for the vtec solenoid which is obviously not there.

also just to clarify i am running the y8 manifolds on the y7.

i am going to check the ecu codes again, as well as the dizzy cap/rotor, firing order, map sensor, tps......i guess if none of these things work i'll be a little lost on what to do next.

another symptom i have noticed is when pressing the throttle and letting off quickly, the engine idles down way too low for a few seconds and then comes back up to where it should be.



Modified by tuner419 at 12:42 PM 9/15/2003

Re: (tuner419)
 

ok firing order is correct, the rotor is new but the cap probably could use replacement....i got the DX ecu to work...it idles now albeit a very low idle. the only ECU code i am getting is for the IACV, which I expected to get w/ the DX ecu because I haven't done the pinouts yet.

still stumbles when pressing the gas more than a little, especially at low rpm's...also i am seeing that there is some kind of fuel cut or something going on at about 1500rpm...almost sounds like its hitting the rev limiter or something but obviously it isn't...i give it more gas and it revs more....limp mode maybe? please advise...
-andrew

Re: (tuner419)
 

well, its always nice when its the simplest possible thing. the spark plugs and cap/rotor needed replacement. runs great now!!!

thanks,
andrew