prunchak03

Hello All,
I bought a Honda Civic EX to commute back and forth to work. I test drove it for a while it was fine. Started to act up I looked into the motor some more and realized it didnt have a Vtec Silonoid and checked the motor number it has a d16y7 motor in it. Im now thinking wtf. So it obviously has a motor swap done so im pissed about that. My idol is wrong in the car. It starts out just fine at about 800. When the car get warmed up the idol drops down to about a steady 300. It cuts in and out slightly when I take off but then is fine again. I changed the plugs and wires in it before i realized the motor change. Could that be an issue as well? also I changed the fuel filter? Could that have somthing to do with it from the different motor? What should I do? Im sure the ecu isnt the right one for that motor. Im going to check that asap. Just want some ideas as to what you think is going on and what I should do. Thanks

Former User

Post what ECU you have.

Any CEL codes?

Have you replaced the cap and rotor and checked the ignition timing?

prunchak03

P1259 is the code im getting. I have not checked the ECU yet. I have to find it. Is it easy to get too to see the number on it? I havent checked the Cap, Rotor or Ignition timing. Ive only had it a few weeks. And just started to notice the problem recently cus i didnt drive it much untill now. Its my work car.

Former User

That VTEC code is a sign that you may have the wrong ECU, though I'm a little surprised that a knock sensor code is not also thrown.

Just remove the front passenger kick panel to view the ECU. Post pictures.

prunchak03

Ok Ill do it tonite when im off work. Ill post pics too. Now would that make it run crappy? Also, how much is an ECU? estimate. Thanks for your help

Former User

A D16Y8 ECU can cause a D16Y7 to have idle problems when there is an IACV incompatibility issue, though you did not mention any IACV code.

I would think that you can purchase a D16Y7 ECU for $100 or less. What year is your Civic?

prunchak03

Its a 1998 civic. And I do believe i actually had a ICAV codes got cleared and so i drove it around the block for about 10 mins came back and i had the P1259 code and a O2 sensor code.

prunchak03

Ok Im home. I found the ECU.




The code it was also throwing was P1259 and said Immobalization to PCM
Hope this is enough info. Let me know if you need more.

Former User

The ECU is for a 98 Civic EX (D16Y8 engine) with an automatic transmission. That explains the VTEC code.

prunchak03

Alrighty, the ECU I need is what for an automatic transmission? Junk yard the best bet or are there better places online?

jvl856

so has this been resolved? i have a similar problem, but the ECU is definately a stock EX 5spd ecu. i tried bypassing the VTEC solenoid by splicing A8 to C15 at the ECU, but it still throws P1259.