Here are the details...please help me out, i know someone has done this swap..
99 d16y8 from an auto going into a 97 hx d16y5. ECU from 98 Manual EX

Since it was an auto engine going into a manual, we swapped the IM w/ TB(for those who don't know, the auto has a 3 wire iacv on the TB itself instead of a 2 wire on the IM on manuals) and exhaust manifold from the HX onto the y8. Also reused the HX dizzy.

Now at first it had some problems when I hooked up the ecu the car wouldn't hold an idle even when the idle screw was adjusted...and it was throwing a primary o2 sensor code. Turns out the HX uses a 5 wire wideband o2 sensor that the ex ecu can't read. So we cleared the codes, and hooked up the HX ecu, adj the idle screw, and got the car to idle at 500rpm's cold, and about 6-700 rpms warm. Car ran fine, no codes, only thing was early vtec switchover at 2700-3200rpm. But it drove very strong.

This weekend we got the right 4 wire o2 sensor hooked up and some other minor stuff. This time the car started up and no codes except for the knock sensor. The car idled even weaker. When i went for a drive it seemed to stumble around 2500-3200rpm. but i was driving from Irvine back to LA so i had to deal. Once I hit the freeway, things seemed okay, but right when i hit about 80mph, the engine seemed to cut back and kinda slow down till i hit about 65mph, then it would kick back into reg power...this happened consistantly.

My question is this...is the knock sensor causing this? do i just have to get it wired up properly? AND do I need to swap my hx dizzy to a ex dizzy to take care of the low idle and stumble? Am I just better off hooking the HX o2 sensor back up and running the hx ecu as it was? I just want the car to run properly, I know i still have to change the tb & im if i want to run the EX ecu and engine better as well as a header or ex EM...help...

 

a help bump...

 

C'mon, 21 reads and no one has any ideas?

 

the dizzy isn't going to cause a low idle...either you're getting spark or you're not, and hopefully it's timed up to specs...which I would also check.

As far as the knock sensor goes, the reason it's stumbling around 2500-3200 is because that's your vtec cross over. When the knock sensor is bad, your car goes into safe mode and retards the ingition timing. During vtec, your car';s timing advances, and with the retarding of the knock sensor, everything goes out of wack and it runs like crap....I've literally broken a couple knock sensors on a turbo B18C5.

So, I would swap out the knock senso, adjust timing, and see where youstand

 

Get a 96-98 EX ecu...if you have the o2 sensor and knock sensor wired right your problems will be gone!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HXMan &raquo;</TD></TR><TR><TD CLASS="quote">Get a 96-98 EX ecu...if you have the o2 sensor and knock sensor wired right your problems will be gone! </TD></TR></TABLE>

He has one....bought it from me. Dizzies are different from the HX to the EX.

 

actually, i am running the 98 ex ecu, we took the good knock sensor off my hx eng, and my wiring had the plug and stuff, but i was told you still need to actually wire it up for the ex ecu?!? that i am confused about, if my harness already has it, isn't it the same pinout for either ecu?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RSZero1 &raquo;</TD></TR><TR><TD CLASS="quote">actually, i am running the 98 ex ecu, we took the good knock sensor off my hx eng, and my wiring had the plug and stuff, but i was told you still need to actually wire it up for the ex ecu?!? that i am confused about, if my harness already has it, isn't it the same pinout for either ecu?</TD></TR></TABLE>

It should be the same pin however, if it was moved by one of the tech's you might want to check that out. D6 should be a red/blue wire.

 

see if it is the same pinout, it should register...it did with the hx ecu? it is in the harness?!? could it be a diff knock sensor?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RSZero1 &raquo;</TD></TR><TR><TD CLASS="quote">see if it is the same pinout, it should register...it did with the hx ecu? it is in the harness?!? could it be a diff knock sensor?</TD></TR></TABLE>

All knock sensors are the same.

EDIT: Maual HX's don't use knock sensors. Only Auto HX's and all EX's use knock sensors.

 

okay, so agreed, that is the main culprit...but i should upgrade my dist since it is higher output for the ex eng compared to my hx dist.