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Ac on= Low idle+ eventually turns off

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Old 09-26-10, 02:47 AM
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Ac on= Low idle+ eventually turns off

My FD has a little issue with the AC!! As i turn on the ac idle goes low..then after few seconds turns off. However if i hold the RPM then it's all good. Please help me fix the problem. Thank you for looking into my thread.
Old 09-26-10, 07:16 AM
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Sounds like the ISC is either bad or unplugged

Look on the back side of the TB/UIM next to the TPS

Old 09-26-10, 11:02 PM
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HERE is a PDF searchable copy of the factory service manual. In it you will be able to find the correct procedure for testing the ISC. It is easy, all you will need is an ohm meter. Post #10 is the money post.

Also, if you have a powerFC make sure the electrical load idle is set higher than the non-load idle.
Old 09-29-10, 12:53 AM
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well..i have removed everything when i took out my emission. So, That's out of the way.. I have checked the voltage..

when the car is running without AC then it reads about 13.3 volts and when the AC is on then it reads 12.3-5 volts. Now, Can that be the alternator???

Some people are telling me, it suppose to stay at 14 volt all the time!!!!!!!!! The car starts up fine, doesn't die on me or nothing...just when i put the AC on then it dies unless i hold the gas pedal...


Help me..
Old 09-29-10, 04:34 AM
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Put the ISC back on, the problem will go away.
Old 09-29-10, 08:23 AM
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*sigh* Another "let's rip off all this BS, boy the car will be better!" The ISC does a good job of keeping the idle where it should be. There's little reason IMHO to remove it.

The AC compressor puts a load on the engine. The ISC will automatically raise the idle to compensate for the additional load.

Also, the voltage from the alternator will drop if the RPM's drop below a normal idle speed. That's totally normal.

Dale
Old 09-29-10, 10:45 AM
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Originally Posted by daleclark
*sigh* another "let's rip off all this bs, boy the car will be better!" the isc does a good job of keeping the idle where it should be. There's little reason imho to remove it.

The ac compressor puts a load on the engine. The isc will automatically raise the idle to compensate for the additional load.

Also, the voltage from the alternator will drop if the rpm's drop below a normal idle speed. That's totally normal.

Dale

+1
Old 09-29-10, 10:50 AM
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I agree your issue is most likely caused by not having the ISC. However I have a similar issue. When I have my AC running it bogs the car down at idle, and my AC does not blow cold on any setting. I have a properly functioning ISC, PFC ECU, and properly charged AC system. I am relatively certain I have a bad AC compressor which is putting more load on the system and not properly compressing the refrigerant. Does this seem likely? Or are there any other probable culprits?
Old 10-01-10, 03:31 AM
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what are the colors on the wires for ISC??
Old 10-02-10, 10:42 AM
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Remember that link I posted for you? Its in there... Electrical diagram is your friend.

That said, and I should just make you look it up, is they are black with white stripe and blue with green stripe.
Old 10-02-10, 04:12 PM
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recently had the same issue and it was a leaking lower intake manifold gasket. If you find that your isc is in place and plugged in, then I would start looking for vacuum leaks.
Old 10-02-10, 11:03 PM
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oo7arkman, RXtacy, Banzai-Racing, DaleClark..............You guys are the best....problem solved..Thank you very much for helping me out...
Old 10-03-10, 05:57 PM
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RXtacy:

Yes your compresser is probably blown and dragging putting extra strain on your engine.
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