idles too low with A/C ON > how do i raise idle?

rebornS14

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or do i have to replace a sensor? I know my idle is supposed to go up when the A/C is on. My other cars usually go up to 1000rpm whereas my 99 LX Ulev Vtec goes limp and struggles at 700ish when my A/C is on.

New to this car so i don't know much about the mechanical but i do work on my own cars so i was hoping a sensor can be replaced or an adjustment can be made.

any info would be helpful. thanks in advance.
 

001Stunna

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or do i have to replace a sensor? I know my idle is supposed to go up when the A/C is on. My other cars usually go up to 1000rpm whereas my 99 LX Ulev Vtec goes limp and struggles at 700ish when my A/C is on.

New to this car so i don't know much about the mechanical but i do work on my own cars so i was hoping a sensor can be replaced or an adjustment can be made.

any info would be helpful. thanks in advance.

Where does the car idle sit at with the A/C off and car warmed up?
Is it 700 -+50 rpm?

I wouldn't mess with the idle screw just yet as it may be a problem with the A/C system.
Have you had the system charged recently? What is the low side pressure at?

It should closely match the below chart
Temp-pressure-chart-33776F.jpg


Have you cleaned the IACV ever?

Have you measured the battery voltage at idle? A/C on? Accessories on but not a/C?
 
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rebornS14

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Where does the car idle sit at with the A/C off and car warmed up?
Is it 700 -+50 rpm?

I wouldn't mess with the idle screw just yet as it may be a problem with the A/C system.
Have you had the system charged recently? What is the low side pressure at?

It should closely match the below chart
Temp-pressure-chart-33776F.jpg


Have you cleaned the IACV ever?

Have you measured the battery voltage at idle? A/C on? Accessories on but not a/C?


i just got this car so no i havent cleaned the IACV and the idle without the A/C on sits at about 700 and with the A/C on it struggles to keep it at 700, it falls a hair under and you can feel the motor struggling. the battery was recently changed at a Honda dealership with a genuine Honda battery. I don't have any records of the A/C being charged but the previous owner seems to have kept ALL of this service records of this car and i didn't catch anything with a A/C charge on it. How do i check the low side pressure?
 

J30MAN

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Yeah check the IACV. Mines going bad. When the car has been driven and I go to get gas or something quick and turn the car back on it idles low as I turn on the heat/AC or even put it in gear.

The part is $90~ and is easy to change. So don't sweat it if thats what the problem is.
 

001Stunna

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i just got this car so no i havent cleaned the IACV and the idle without the A/C on sits at about 700 and with the A/C on it struggles to keep it at 700, it falls a hair under and you can feel the motor struggling. the battery was recently changed at a Honda dealership with a genuine Honda battery. I don't have any records of the A/C being charged but the previous owner seems to have kept ALL of this service records of this car and i didn't catch anything with a A/C charge on it. How do i check the low side pressure?

How did the issue start?
Did it happen as soon as you bought the car or have you owned it for a while and now it started?

To check the a/c you need a a/c gauge to connect to lowside port, or if you want to be fully correct you need an a/c manifold.

That being said, Have you measured the battery voltage at idle? A/C on? Accessories on but not a/C?
 

RichBinAZ

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I recommend against those single pressure measuring and re-charging tools. I tried them once and screwed it up. You need to measure both pressures at the same time or have a dealer do it.
 

001Stunna

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I recommend against those single pressure measuring and re-charging tools. I tried them once and screwed it up. You need to measure both pressures at the same time or have a dealer do it.

Its pretty hard to screw it up...unless you just keep charging not looking at the gauge or not doing the preparation steps right. In which case...you're the only thing to blame.
 

rebornS14

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sorry i took so long. life...

battery with engine off 12.45

battery with engine on 14.55

battery with engine and A/C on 14.28

so i dont think its my alternator
 

Frisky Arab

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Is the A/C blowing cold in the car even if its hot outside and the engine has been running? I know my car struggles a bit when I turn the A/C, and my car needs freon. I know it needs freon cuz it won't blow cold if its too hot outside. Which sucks...
 
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