vafc sensor check... what does yours say?
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From: Atlantis
vafc sensor check... what does yours say?
There are three values there for voltages being read...
What are they/ should they be?
I'm assuming they're reading off the sensors, but which one reads which and why?
Check with motor off and key in acc position, and again with car idling.....
[Modified by Black R, 5:15 PM 6/20/2002]
What are they/ should they be?
I'm assuming they're reading off the sensors, but which one reads which and why?
Check with motor off and key in acc position, and again with car idling.....
[Modified by Black R, 5:15 PM 6/20/2002]
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From: Umm..., NJ
Re: vafc sensor check... what does yours say? (Black R)
I am not to sure what they are exactly supposed to be. But here are the voltages I get with my car.
Car Off
Pressure: 2.930 +/- .005
Throttle: .475 +/- .005
CDS: 2.050 +/- .005
Car On
Pressure: .990 +/- .020
Throttle: .485 +/- .005
CDS: 2.500 +/- .005
Im am pretty sure that pressue is reading from the map sensor, throttle is from the TPS, and CDS is the display output for the screen. Those are the readings my car gives, and it seems to run fine. Are you having problems with yours?
Car Off
Pressure: 2.930 +/- .005
Throttle: .475 +/- .005
CDS: 2.050 +/- .005
Car On
Pressure: .990 +/- .020
Throttle: .485 +/- .005
CDS: 2.500 +/- .005
Im am pretty sure that pressue is reading from the map sensor, throttle is from the TPS, and CDS is the display output for the screen. Those are the readings my car gives, and it seems to run fine. Are you having problems with yours?
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From: Atlantis
Re: vafc sensor check... what does yours say? (Black R)
ok, with the car in acc and motor off:
Pres = 2.79
Thrt = .410 (pressing pedal to wot = 4.485)
CDS = 5.010
With the car idling:
Pres = 1.2-1.5
Thrt = .1-1.2 (4.3 at wot)
CDS = 4.985
Anyone else?
Pres = 2.79
Thrt = .410 (pressing pedal to wot = 4.485)
CDS = 5.010
With the car idling:
Pres = 1.2-1.5
Thrt = .1-1.2 (4.3 at wot)
CDS = 4.985
Anyone else?
Joined: May 2002
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Re: vafc sensor check... what does yours say? (Black R)
With the car idling:
Pres = 1.2-1.5
Thrt = .1-1.2 (4.3 at wot)
Pres = 1.2-1.5
Thrt = .1-1.2 (4.3 at wot)
Throttle should be a little under (.025V) .5 Volts at idle but you can adjust that.
[Modified by Centripetal, 2:58 AM 6/24/2002]
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Thread Starter
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From: Atlantis
Re: vafc sensor check... what does yours say? (Centripetal)
You should be about .94 Volts (according to Honda) at idle. Since you are at about 1.2-1.5 I would assume that your rings and/or valves are not sealing properly. Do a valve adjustment and see if that make a difference. However, if that does not help, time for a rebuild.
Throttle should be a little under (.025V) .5 Volts at idle but you can adjust that.
[Modified by Centripetal, 2:58 AM 6/24/2002]
Throttle should be a little under (.025V) .5 Volts at idle but you can adjust that.
[Modified by Centripetal, 2:58 AM 6/24/2002]
Maybe that pressure reading is due to my spec B's.
I'm due for a valve lash adjustment though. After that, I'll do a compression test and leakdown test. 13k on this almost new motor.....
=
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From: Charlotte
Re: vafc sensor check... what does yours say? (Black R)
Car in acc and motor off:
Pres = 2.920
Thrt = .480 (pressing pedal to wot = 4.615)
CDS = 3.940
With the car idling:
Pres = 0.85-0.93
Thrt = 0.480 (did not check @ wot)
CDS = 3.805
Pres = 2.920
Thrt = .480 (pressing pedal to wot = 4.615)
CDS = 3.940
With the car idling:
Pres = 0.85-0.93
Thrt = 0.480 (did not check @ wot)
CDS = 3.805
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Re: vafc sensor check... what does yours say? (Centripetal)
With the car idling:
Pres = 1.2-1.5
You should be about .94 Volts (according to Honda) at idle. Since you are at about 1.2-1.5 I would assume that your rings and/or valves are not sealing properly. Do a valve adjustment and see if that make a difference. However, if that does not help, time for a rebuild.
Throttle should be a little under (.025V) .5 Volts at idle but you can adjust that.
Pres = 1.2-1.5
You should be about .94 Volts (according to Honda) at idle. Since you are at about 1.2-1.5 I would assume that your rings and/or valves are not sealing properly. Do a valve adjustment and see if that make a difference. However, if that does not help, time for a rebuild.
Throttle should be a little under (.025V) .5 Volts at idle but you can adjust that.
I'm stumped. Can anyone help, or give me some clues as to what to do next?
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From: Delaware
Re: vafc sensor check... what does yours say? (Chris N)
With the car idling:
Pres = 1.2-1.5
You should be about .94 Volts (according to Honda) at idle. Since you are at about 1.2-1.5 I would assume that your rings and/or valves are not sealing properly. Do a valve adjustment and see if that make a difference. However, if that does not help, time for a rebuild.
Throttle should be a little under (.025V) .5 Volts at idle but you can adjust that.
I just finished soldering and installed my harness/vafc. Upon turning the car on, I found that the Pressure = .50-.70, nowhere near .94V as it should be. All connections are good. Also, my throttle % reading is off. It stays at 0 most of the time and moves upward only when a significant change is % is realized, then returns to zero.
I'm stumped. Can anyone help, or give me some clues as to what to do next?
Pres = 1.2-1.5
You should be about .94 Volts (according to Honda) at idle. Since you are at about 1.2-1.5 I would assume that your rings and/or valves are not sealing properly. Do a valve adjustment and see if that make a difference. However, if that does not help, time for a rebuild.
Throttle should be a little under (.025V) .5 Volts at idle but you can adjust that.
I just finished soldering and installed my harness/vafc. Upon turning the car on, I found that the Pressure = .50-.70, nowhere near .94V as it should be. All connections are good. Also, my throttle % reading is off. It stays at 0 most of the time and moves upward only when a significant change is % is realized, then returns to zero.
I'm stumped. Can anyone help, or give me some clues as to what to do next?
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Re: vafc sensor check... what does yours say? (sneakychaos)
All connections are correct. I'm really very fed up with this thing. Got a CEL last night while driving down the street and ended up taking out the field harness and vafc right there and moving on. It was WAY too cold to check the CEL, but I suspect it is because of a bad connection or something similar.
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Re: vafc sensor check... what does yours say? (B2FiNiTY)
I"m seriously considering Hondata at this point. Not just because I'm having trouble hooking the vafc up, but it certainly is contributing to the idea. All this work, for what? The time I'll spend tuning (and the tuning money, i can't wait 
), soldering/hooking this thing up and tuning more, I could have a much better engine management system.
), soldering/hooking this thing up and tuning more, I could have a much better engine management system.
Re: vafc sensor check... what does yours say? (Chris N)
Which source did you use to connect the wires? Maybe they are connected wrong. http://www.apexi-usa.com has an updated manual for 00-01 ITR's
Re: vafc sensor check... what does yours say? (Chris N)
What source did you use to connect the wires. 97-98 wiring differ from the 00-01. I'm just taking a stab at anything because I have no clue what could be wrong with your install.
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Re: vafc sensor check... what does yours say? (B2FiNiTY)
I used 00-01 diagram. I also checked everything with the '00 helms update with the ecm/pcm pin locations, since I was using the field vtec harness. I'm sure everything is in there ok.
Let us know what the CEL is. 
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From: Chicago, IL, USA
Re: vafc sensor check... what does yours say? (Chris N)
A shot in the dark from audio/security install troubleshooting woes...
Do you have a multimeter handy? If so, see if you can get a voltage reading on those wires that seem to be sending the wrong signals. Also...try a different ground. Those sound like such easy things...but I won't even begin to count how many times those have been the culprits when installing things on various cars in my life.
I'll probably install mine this weekend...hopefully.
Do you have a multimeter handy? If so, see if you can get a voltage reading on those wires that seem to be sending the wrong signals. Also...try a different ground. Those sound like such easy things...but I won't even begin to count how many times those have been the culprits when installing things on various cars in my life.
I'll probably install mine this weekend...hopefully.