ECU and other auto to manual swap woes...

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New Member
Alright, so i have a few questions so ill try to make this as organized as possible. I accidentially posted this in the hybrid forums aswell.

For my auto to manual swap i used this thread...
[FAQ] 96-00 Auto to Manual Swap in full detail!! (44pics) - Honda-Tech

For my y8 throttle body installation i used these sites in addition to ALLDATA for wiring and hoses.
My y7 to y8 Intake Manifold Swap (pics) - Page 4 -
Swapping a y8 intake manifold onto a y7 -

A little background on my car,
I have a 99 Civic VP which was stock aside from a short ram intake. Tranny went out so i decided to swap to manual. Did the swap including a manual y8 intake w/ a felpro gasket, and P2E-A12, rewired the IACV and d-pinned the harness. Tried starting the car and it was running rough (later found out my friend mixed up the plug wires) and threw P0505 for the iacv. I blocked off the holes with a sheet of gasket paper and rewired back to 3-wires and installed the y7 throttle body, fixed firing order.

Now that it's running, it will start and idle normal for a few seconds then revs up and drops, then revs up and drops, The iacv hole is also very loud and when i cover the larger portion of it, the idle drops to normal. So i cleaned it and wiggled the rotor a little to make sure it wasn't stuck, but the problem remained. Although, when i remove the plug from my tps the idle settles but doesn't have the same power.

I will be testing their voltages and all that tomorrow if my homie comes through with a multimeter. I am other wise wondering about the whole ecu deal. I have already purchased two ECUs, one OBD2a on accident, the second(the P2E-A12) which is a non-vtec 3-wire ECU. If my iacv is bad, i would hate to buy a new one when there is one bolted to the back of the throttle body.

So my questions now, :).

First, would it be cheaper to find another ECU that is 2-wire? and which one would i get? I went through this list
in addition to this list
Applications By Vehicle

The ECUs suggested in the first link are all vtec, but i don't have a vtec and don't want to be throwing vtec codes at the smog man. Also are OBDII-->OBDI jumpers legal in California? In case I am required to get one.

Also, i adjusted my valve lash and I torqued my cam pulley bolt to 45lb*ft, later finding out its only 27lb*ft. Should i just leave it, replace it with a new one, or back it out an re torque it to spec?

And my coil went out last night(confirmed with test light), any one have good experiences buying them online? or with those transparent cap and rotor kits?

If you made it to here, your almost done reading and i love you. I hope you have some answeres or enlightnement to my situation.

Thanks for reading,


Honda Minion
The hunting idle definitely reads like a IACV thing. You will have that going on at running temps without the IACV

Explain the wiring situation of the IACV again (as it pertains to being rewired and such)

Does the new IM take a different IACV?


Honda Minion
Also....the OBD2-OBD1 conversion that's not legal in CA smog. But he won't look unless other things ate going on.

No CEL....pass sniffer.....pass visual....pass gas tank lid check....done.

Why are you running a OBD1 ECU?


New Member
As for the iacv, there is one on the back of the intake manafold(2-wire) which has some gasket paper to block the holes. This was done because I received code P0505 and a misfire code which was the plug wires being wrong.
When researching the codes I discovered that my OBDIIb P2E-A12 ECU is designed for a 3-wire valve. So i put my auto y7 throttle body on for the iacv, got the car started and running, but the idle was all jacked up, cleaned the iacv, checked for leaks, used a y7 auto TB gasket, bled coolant.

The only things that work are to unplug the TPS which seems to affect performance, or to hold my finger over most of iacv hole inside the throttle body. Although my coil went out the other night and im kinda broke at the moment.


New Member
The coil went out during a drive when i was attempting to "re learn" the idle so i don't know the results of that yet, hah.

Also, i re-pinned the ecu to 2 wire iacv when attempting with the one on the intake, and back to 3 wires when i switched back to the y7 throttle body.

Ohh and the Ecu, I was just wondering about the price difference and opinions on whether I buy a new iacv or buy an OBDI with a jumper that will run the 2-wire iacv. I have already bought two ecus, and want advice before possibly purchasing a third.

What would be a good ECU to get that runs a 2-wire iacv and is not that rare to find. Remember though, I am not running a vtec head, just the intake manifold.