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missing/idling rough with a/c on.

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Old 07-10-2010, 03:46 AM
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Default missing/idling rough with a/c on.

I've been noticing with my a/c on my battery goes well below normal, as well if I use my power windows. It's been acting like it wants to die(i notice the battery gauge jump down and back up). It's got a new battery and terminals on as well as starter and ignition switch just recently.

usually the truck idles alittle higher than normal but when sitting with the a/c on it will sometimes go below 600 rpm.

Today I noticed the batter gauge jump up and down even without the a/c on, is there something I can check or a possibly remedy?

I'm going to check for codes asap(probably monday because of work)

other than that it runs awesome, just notice this happen when I'm at a complete stop sitting for a while.

I really don't know if it's missing but it does significantly lose alot of power.
Old 07-10-2010, 10:47 AM
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Might want to have a new alternator ready to put on - from what you indicated either the regulator or the whole unit is probably going to give up the ghost pretty soon...
Old 07-10-2010, 12:19 PM
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Check Alt. output. At Idle & under load. Is your rpm 650 min. to start w/?

If it is your alternator, go w/ a 95 amp 3G Model for replacement. http://www.fordfuelinjection.com/?p=75

Try cleaning & testing your IAC! http://www.fordfuelinjection.com/?p=39

Last edited by ymeski56; 07-10-2010 at 12:22 PM.
Old 07-11-2010, 06:07 AM
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what would a truck with a 302 generally run at? sorry I won't be able to get numbers until monday/tues
Old 07-11-2010, 10:36 AM
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Originally Posted by Spikebrian
what would a truck with a 302 generally run at? sorry I won't be able to get numbers until monday/tues
650-675 rpm warm curb idle.Try cleaning & testing your IAC valve. http://www.fordfuelinjection.com/?p=39 Running Error code scans are a good idea too. But, A bad IAC won't show up in an error code scan because it's a valve, not a sensor. However, you can still check it's function as mentioned on the link.

Last edited by ymeski56; 07-11-2010 at 10:48 AM.
Old 07-12-2010, 04:00 AM
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Originally Posted by ymeski56
Check Alt. output. At Idle & under load. Is your rpm 650 min. to start w/?

If it is your alternator, go w/ a 95 amp 3G Model for replacement. http://www.fordfuelinjection.com/?p=75

Try cleaning & testing your IAC! http://www.fordfuelinjection.com/?p=39

When i start the truck it idles at 1500 for about 25 seconds and stays constantly at 1000. Its rare for it to drop below that other than the most recent issues.
Old 07-12-2010, 11:01 AM
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Originally Posted by Spikebrian
When i start the truck it idles at 1500 for about 25 seconds and stays constantly at 1000. Its rare for it to drop below that other than the most recent issues.

When my Alt. died completely a couple of weeks ago, while showing a discharge, my idle stayed at 1K rpm

Last edited by ymeski56; 07-12-2010 at 11:06 AM.



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