AACV??? (long stupid question)
AACV??? (long stupid question)
So i finally get my car running and driving, the night before i went to the dyno (a few weeks ago) i decide to check a few things..checked my TPS and it was way off, so i replaced it and set it properly.
now, with the TPS set properly i've noticed a high idle (in the neighborhood of 1600rpm, 2000-2200rpm on cold start). went through the FSM and followed the procedure to set the idle. going through that i've found i've got an overactive auxiliary air control valve. while i had part of the motor in pieces a few months ago i took the IACV/AACV apart and cleaned them with carb cleaner and a tooth brush and now this! should i be lubing the spring? does the AACV come apart like the IACV? as of now i'm driving around with the AACV unplugged and 1100rpm idle with everything electrical off, 600-700 with headlights on (i keep my fogs off because of this actually). i cant turn the fan on when idling w/lights on, stereo has to be way down, i have to hold the revs above idle to turn the wheel at a stop (backing out of tight parking spots is pretty annoying at night). its rough stuff. all i ask is that it idle right.
what i'm wondering is, could there be another sensor that i havent thought of thats sending the ECU a wrong signal to open the AACV all the time? i can hear it sucking a ton of air when i plug it in. if i need to get a new AACV i'll get one, but i'd rather not.
now, with the TPS set properly i've noticed a high idle (in the neighborhood of 1600rpm, 2000-2200rpm on cold start). went through the FSM and followed the procedure to set the idle. going through that i've found i've got an overactive auxiliary air control valve. while i had part of the motor in pieces a few months ago i took the IACV/AACV apart and cleaned them with carb cleaner and a tooth brush and now this! should i be lubing the spring? does the AACV come apart like the IACV? as of now i'm driving around with the AACV unplugged and 1100rpm idle with everything electrical off, 600-700 with headlights on (i keep my fogs off because of this actually). i cant turn the fan on when idling w/lights on, stereo has to be way down, i have to hold the revs above idle to turn the wheel at a stop (backing out of tight parking spots is pretty annoying at night). its rough stuff. all i ask is that it idle right.
what i'm wondering is, could there be another sensor that i havent thought of thats sending the ECU a wrong signal to open the AACV all the time? i can hear it sucking a ton of air when i plug it in. if i need to get a new AACV i'll get one, but i'd rather not.
After installing the new TPS, you have to reset it with respect to the computer. After installing it and adjust the CTPS to trigger once the gas peddle is released (like the fsm says), start the car, and while its running unplug the TPS (lower connector) and plug it back in again. This is what I had to do when installing a new TPS.
BTW, you must have the AAC confused with the IACV, b/c the AAC (purple connector) only operates when the A/C is turned on, and it raises the rpm by about 100 by allowing more air to enter the IACV.
BTW, you must have the AAC confused with the IACV, b/c the AAC (purple connector) only operates when the A/C is turned on, and it raises the rpm by about 100 by allowing more air to enter the IACV.
Originally Posted by eric93SE
After installing the new TPS, you have to reset it with respect to the computer. After installing it and adjust the CTPS to trigger once the gas peddle is released (like the fsm says), start the car, and while its running unplug the TPS (lower connector) and plug it back in again. This is what I had to do when installing a new TPS.
BTW, you must have the AAC confused with the IACV, b/c the AAC (purple connector) only operates when the A/C is turned on, and it raises the rpm by about 100 by allowing more air to enter the IACV.
BTW, you must have the AAC confused with the IACV, b/c the AAC (purple connector) only operates when the A/C is turned on, and it raises the rpm by about 100 by allowing more air to enter the IACV.
i have no a/c, but i was under the impression the AAC would raise the idle when the radiator fans came on or if the idle dropped a certain amount regardless..could the a/c removal have something to do with it? i've had this problem since i removed the compressor. before this i could press the a/c button and the idle would raise along with the radiator fans going on even though the a/c belt was removed. hmmmmm
Any ECU error codes?
TPS resistor should be linear 1kOhm-9k. Even new one can be bad...
ECU controls the A/C, cuts the compr clutch off while accel, rises idle if the compressor is running.
"...could the a/c removal have something to do with it? i've had this problem since i removed the compressor. "
Sounds like your probl timing is there but also poss coincidence... Think what elese happened at that time.
I could be at least possible that taking compressor out would confuse the ECU. Depends how its programmed, is ECU always ? checking some rev reading (resistance) from the compressor.
Easy test for your theory is simply to connect the compressor wirings back. If that is the problem, put it back without the belt...
TPS resistor should be linear 1kOhm-9k. Even new one can be bad...
ECU controls the A/C, cuts the compr clutch off while accel, rises idle if the compressor is running.
"...could the a/c removal have something to do with it? i've had this problem since i removed the compressor. "
Sounds like your probl timing is there but also poss coincidence... Think what elese happened at that time.
I could be at least possible that taking compressor out would confuse the ECU. Depends how its programmed, is ECU always ? checking some rev reading (resistance) from the compressor.
Easy test for your theory is simply to connect the compressor wirings back. If that is the problem, put it back without the belt...
Originally Posted by Wiking
Any ECU error codes?
TPS resistor should be linear 1kOhm-9k. Even new one can be bad...
ECU controls the A/C, cuts the compr clutch off while accel, rises idle if the compressor is running.
"...could the a/c removal have something to do with it? i've had this problem since i removed the compressor. "
Sounds like your probl timing is there but also poss coincidence... Think what elese happened at that time.
I could be at least possible that taking compressor out would confuse the ECU. Depends how its programmed, is ECU always ? checking some rev reading (resistance) from the compressor.
Easy test for your theory is simply to connect the compressor wirings back. If that is the problem, put it back without the belt...
TPS resistor should be linear 1kOhm-9k. Even new one can be bad...
ECU controls the A/C, cuts the compr clutch off while accel, rises idle if the compressor is running.
"...could the a/c removal have something to do with it? i've had this problem since i removed the compressor. "
Sounds like your probl timing is there but also poss coincidence... Think what elese happened at that time.
I could be at least possible that taking compressor out would confuse the ECU. Depends how its programmed, is ECU always ? checking some rev reading (resistance) from the compressor.
Easy test for your theory is simply to connect the compressor wirings back. If that is the problem, put it back without the belt...
this TPS is good, the voltage range is correct, it reads consistantly where its set (monitoring via SAFC sensor test mode), resistance is right on par with the FSM. i know the TPS is no longer an issue. timing is quite a bit advanced but i doubt that'll have this affect on it (as i've had the timing set the same before this issue came up). i know its possibly just a coincidence but i highly doubt it as i thought the issue was several other things (which also turned out to be bad ex: vacuum leaks that couldnt be heard clearly/seen, bad EGR tube seal, bad TPS) and fixed them all with very little improvement.
as far as what else could have happened, there are several options as i pulled the motor and rebuilt it when i removed the a/c system. i would have already reconnected the compressor to test my theory however its been long since sold.
just checked and the brown connector is unplugged, and it is infact the one on the "right" side of that assembly..going outside again to see if i'm an idiot and mixed up the plugs. IIRC the connectors are different but we'll see.
edit: i didnt remember the connectors were color coded
i'll have to unplug the purple and plug in the brown when i get home and see what happens.
not sure if i mentioned this before but when the radiator fans turn on (i assume from coolant temp sensor signal) the idle does NOT go up.
also i do have a high idle for cold starts (1400rpm) which settles to 1100 during the instances i mentioned above.
edit: i didnt remember the connectors were color coded

i'll have to unplug the purple and plug in the brown when i get home and see what happens.
not sure if i mentioned this before but when the radiator fans turn on (i assume from coolant temp sensor signal) the idle does NOT go up.
also i do have a high idle for cold starts (1400rpm) which settles to 1100 during the instances i mentioned above.
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hez8813
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