djkeene1993

Hey everyone I have a 92 civic CX with 110,000 miles it had the original d15b8 5 speed in it about a week ago. I swap in a y8 auto head onto it. I have followed for the most part Dan's massive y8 on d15b block write up. So here is soke background info. The y8 intake manifold had the three wire iacv originally on the TB I removed that and sealed up holes. I drilled three holes in it so I could use my two wire iacv( don't know if this could be causing problems or not). I am also using my original ECU I believe it is a p05 or p2p I have a p28 as well but the car idles up and down quickly with it plugged in. I also have a adjustable cam gear on it which I've read it needs to be 2.75 degrees off but it seems to run alot better set at 0. I had the head plained and I put new valves and springs in it, all new upper gaskets water pump timing belt y8 spark plugs and wires. So after I got everything hooked up and running somewhat decent I still have some kinks to work out. here is my problem when I start the car up it fires right up and seems to idle fine maybe a little high but anyways I can move the car but it sputters slightly for about 30secs to a min then a cel comes on and it doesn't sputter any more but under load, driving down the road i can tel it doesn't have full power almost sounds if it is bogged down. I have tried to pull a code off it I got nothing it gives me a solid cel with no codes. I just swapped in my map sensor from the old intake manifold did nothing. I've checked vacum leaks adjusting ignition timing. Also I did not have a cel on before I started. I don't what else to try. Any ideas or input on this would be awesome. Thanks

mk378

Set adjustable cam gears to zero unless professionally tuned by someone who knows exactly what they're doing. Usually you would keep the OBD1 intake manifold and just swap the head. When CEL comes on, put the jumper in with the engine still running; don't turn key off. This should show you the code. (if codes are being forgotten every time you turn the key off, the "BACK UP" fuse under the hood is likely blown) Make sure all harness plugs are plugged into the right parts. Check TPS with a voltmeter. Set spark timing with a light. If spark timing seems way off, the timing belt may be off by a tooth.

Loyalhondahaver

Some excellent advise there^

djkeene1993

Ok I will set cam to zero check tps and try getting a cel code again. I was hoping to keep the bigger intake manifold for better airflow but if all none of the above work will switch it out as well. Thanks again for the advise

Former User

Which of the ECUs are you using? The P28 would be the best match for your set up.

djkeene1993

Im currently using a p05. When I use the p28 it revs up and down very quickly. I would rather use the p28 though, could the timing be off a half a tooth with the p28 maybe and that be causing the revs? Or maybe because of o2 wires not being hooked up? I'm fairly new to this sorry

Former User

The idle surge is more likely due to your IACV work, a dirty IACV, or an intake air leak.

Was the Y8 IM taken from a 99-00 Civic with an FIA system?

djkeene1993

I sprayed a can of starter fluid all around the intake and didn't find any leaks. My guess is my work on the iacv I think I'll try switching the intake manifold and then try the p28 ECU as well. Thanks

djkeene1993

Yes I believe so. it is an auto y8 intake manifold with the 3 wire iacv on the TB. Why?

Former User

You believe the Y8 IM came from a 99-00 Civic?

djkeene1993

Yes

Former User

The FIA that is specific to the 99-00 Civic Y8 IM is a common source of an intake air leak in hybrid engine swaps.

djkeene1993

It has a vacum line going to the top of it in front of the injectors. like the one the picture. I ran that line to the sensor and the sensor is not plugged in as it is not used. In a another forum I read you cap off the inlet on top of the manifold and cap off sensor as well.

djkeene1993

Should I cap it off or is there a better way to do it?

Former User

A leak in the blocked off FIA could cause the problem, so double check your work.

You may need to plug the FIA passageways in the Y8 IM.

djkeene1993

Ok thanks will check that as well.

djkeene1993

Ok so I have completely blocked off the FIA system on the y8 IM. I have switch the ECU to a p28( converted this to manual first) I then went ahead set the cam gear to zero. Started it and it idled fine at first. But I still have a cel so I checked for codes I got 21 and 41. 21 is vtec( I do not have this wired in yet) 41 is a primary oxygen sensor heater. Most forums say that its usually is a bad o2. Should I replace this? I did not have a cel on before I started. I got the code 41 when car was idling ok but sometimes it will surge pretty bad but shut it off and start it up again may or may not do it again should I check for codes when the idle is surging?

Former User

Reset the ECU to see whether code 41 returns.

djkeene1993

Yes code 41 comes back

Former User

Ohm test the heater element and check whether it receives voltage from the connector.

djkeene1993

Sorry I just stop posting been working alot the past week but anyways. Here is an update. I went head and bought a new four wire o2 sensor since the p28 requires a 4 wire o2 (at least from what I have read). Wired it in and I am no longer getting a cel for anything other than my vtec. It is still running like crap idle surging alot now. I am swaping in my old d15 intake manifold to see if this helps. If this doesnt what then???