IACV: Needs to be replaced, adjusted or ???
10-09-2009, 12:13 AM
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IACV: Needs to be replaced, adjusted or ???
I have a '00 Honda Civic CX, d16y7. I did a mini-me, d16y8 head, ECU & harness. I put a Skunk2 intake manifold and a STP 68mm throttle body. My car throws "check engine" light. I scanned it and it says its IACV is bad. I cleaned it out and it still does. The two hoses are not connected but when I opened that part to clean there is nothing there but an empty space. The car lacks ***** up to about 3k rpms then runs good. Could it be because of the two hoses or my IACV is bad? Any help would help and thanks in advance to all!
Last edited by JDM.K24; 10-09-2009 at 06:27 PM.
10-09-2009, 08:47 AM
#5
Re: IACV: Needs to be replaced or adjusted?
The hoses feed engine coolant to and from the IACV in order to warm a thermowax within the IACV. This thermowax expands with heat (or conversely retracts with colder temperatures) allowing less or more air through per associated temperatures. Once on the cold side (it allows more air through in order to compensate for cold climates).
What I would do is run temporary wires from the battery (or small gator clips) to the IACV solenoid in order to see if it actuates (if you hear a click). If you don't hear anything, it isn't functioning at all.
What I would do is run temporary wires from the battery (or small gator clips) to the IACV solenoid in order to see if it actuates (if you hear a click). If you don't hear anything, it isn't functioning at all.
10-09-2009, 09:21 AM
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10-09-2009, 09:26 AM
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Re: IACV: Needs to be replaced or adjusted?
The hoses feed engine coolant to and from the IACV in order to warm a thermowax within the IACV. This thermowax expands with heat (or conversely retracts with colder temperatures) allowing less or more air through per associated temperatures. Once on the cold side (it allows more air through in order to compensate for cold climates).
What I would do is run temporary wires from the battery (or small gator clips) to the IACV solenoid in order to see if it actuates (if you hear a click). If you don't hear anything, it isn't functioning at all.
What I would do is run temporary wires from the battery (or small gator clips) to the IACV solenoid in order to see if it actuates (if you hear a click). If you don't hear anything, it isn't functioning at all.
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10-09-2009, 11:45 AM
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Re: IACV: Needs to be replaced or adjusted?
doesnt the cx/dx intake manifold have a three wire iacv and the ex have a two wire???
just wondering i dont remember, if so then there is your problem
just wondering i dont remember, if so then there is your problem
10-09-2009, 12:16 PM
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10-09-2009, 01:43 PM
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Re: IACV: Needs to be replaced or adjusted?
Yeah that is true it is a three wire(CX/DX) and EX two wire. And there is a orange wire not connected to anything on plug for the IACV, on the harness. I have the '99-'00 OBD2b EX ECU and harness though...
10-09-2009, 01:45 PM
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Re: IACV: Needs to be replaced or adjusted?
The hoses feed engine coolant to and from the IACV in order to warm a thermowax within the IACV. This thermowax expands with heat (or conversely retracts with colder temperatures) allowing less or more air through per associated temperatures. Once on the cold side (it allows more air through in order to compensate for cold climates).
What I would do is run temporary wires from the battery (or small gator clips) to the IACV solenoid in order to see if it actuates (if you hear a click). If you don't hear anything, it isn't functioning at all.
What I would do is run temporary wires from the battery (or small gator clips) to the IACV solenoid in order to see if it actuates (if you hear a click). If you don't hear anything, it isn't functioning at all.
10-09-2009, 02:28 PM
#12
Re: IACV: Needs to be replaced or adjusted?
Oh, the other responses suggest you may have a three wire and I don't know how the three wire version works offhand. Do you have a 3 or 2 wire version?
10-09-2009, 05:44 PM
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Re: IACV: Needs to be replaced or adjusted?
The IACV is a solenoid (which is basically just a plunger style rod that goes back and forth). If there is a hum and not a click, I am figuring it is jammed/plugged up. There is a thread somewhere on how to clean it but be careful.
Oh, the other responses suggest you may have a three wire and I don't know how the three wire version works offhand. Do you have a 3 or 2 wire version?
Oh, the other responses suggest you may have a three wire and I don't know how the three wire version works offhand. Do you have a 3 or 2 wire version?
10-10-2009, 01:28 PM
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Re: IACV: Needs to be replaced, adjusted or ???
Connected the coolant hoses to the IACV and it still it throwing check engine even after I reset it. I am thinking it is gonna be the third(orange) wire thats not connected or my IACV is bad. Can anyone help me out!?!
10-10-2009, 02:27 PM
#15
Re: IACV: Needs to be replaced, adjusted or ???
What the others in this thread are saying is that with the swap, the IACV needed to be converted from a 3 wire to a 2 wire design. This was done by cutting the orange wire (and ignoring it) and running the yellow/black and black/blue wires to the 2 wire IACV (which according to the pictures, was probably done right).
With this changeover, the instructions posted by others suggest you need to move the wire on your ECU plug A from position A14 to A12 thereby wiring up the IACV to the appropriate ecu output. If this wasn't done, it probably won't work.
Hope that helps but please note, I have not worked on your engine nor on any OBD2 engine.
10-11-2009, 02:21 PM
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Re: IACV: Needs to be replaced, adjusted or ???
Anyone know if this is what I need to do? Might sound like a dumb question but just learning about all this. Any and all help is appreciated!
10-12-2009, 08:17 AM
#17
Re: IACV: Needs to be replaced, adjusted or ???
I found a pinout for your (assuming you have OBD2b) ecu. It appears that your find is correct. B23 is IACV (black/blue) and B15 is IACV negative (which is not used since you are using the yellow/black wire).
http://www.ff-squad.com/technet/wiring.obd2b.htm
p.s. I have ff-squad bookmarked
http://www.ff-squad.com/technet/wiring.obd2b.htm
p.s. I have ff-squad bookmarked
10-12-2009, 09:01 AM
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Re: IACV: Needs to be replaced, adjusted or ???
yeah looks like i jumped the gun and didnt pay attention to obd2a vs b. so basically for the 2-wire iacv and obd2b ecu. one pin goes to b23 and the other gets ignition power
10-12-2009, 09:16 AM
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Re: IACV: Needs to be replaced, adjusted or ???
I found a pinout for your (assuming you have OBD2b) ecu. It appears that your find is correct. B23 is IACV (black/blue) and B15 is IACV negative (which is not used since you are using the yellow/black wire).
http://www.ff-squad.com/technet/wiring.obd2b.htm
p.s. I have ff-squad bookmarked
http://www.ff-squad.com/technet/wiring.obd2b.htm
p.s. I have ff-squad bookmarked
...yeah gonna bookmark it too!
10-12-2009, 09:17 AM
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Re: IACV: Needs to be replaced, adjusted or ???
10-12-2009, 02:54 PM
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Re: IACV: Needs to be replaced, adjusted or ???
Did the pin out fix and still throwing check engine even after I reset it. Could it be the IACV that is just bad now? HELP!!!
Last edited by JDM.K24; 10-12-2009 at 03:21 PM.
10-12-2009, 06:18 PM
#22
Re: IACV: Needs to be replaced, adjusted or ???
and I know, throwing money at a problem really bites.
EDIT: if you do the LED idea, make sure you have appropriate polarization and a current limiting resister in series
10-13-2009, 01:17 AM
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Re: IACV: Needs to be replaced, adjusted or ???
IACV does not need to have coolant running to and from it in order to function correctly, so dont worry about them.
10-13-2009, 10:20 AM
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Re: IACV: Needs to be replaced, adjusted or ???
Start your engine, unplug the IACV and take a voltage readout. You should generally have 12+volts between the 2 wires. What I tried to do was run an LED from the 2 nodes to be sure the IACV was getting power. That way, I could understand things by comparing how the engine ran with the IACV LED indicator.
and I know, throwing money at a problem really bites.
EDIT: if you do the LED idea, make sure you have appropriate polarization and a current limiting resister in series
and I know, throwing money at a problem really bites.
EDIT: if you do the LED idea, make sure you have appropriate polarization and a current limiting resister in series