99 ranger bad idle
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From: utah
99 ranger bad idle
hey yall. i have a problem with my idle sometimes, i wont actually stall, but will only happen when i turn on my heat or a/c, i already checked my pcv and my r-134 level, any suggestions my eng is a 2.5 4 banger. thanks all. also it seems that my comp. kicks in and out more often than usual.
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Hey, I've seen that problem before. Before you try anything else....turn off your blower motor and turn your heat setting to the floor instead of defrost or defrost/floor mixture. Once you have done this see if your compressor is still cycling - if it stops cycling you are low on refrigerant. When the compressor comes on it will draw more power from the engine which will cause the motor idle to go down. On newer vehicles - anytime you select the defrost or defrost/floor mixture the AC will cycle - even in the winter.
Post Fiend
Joined: Feb 2003
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From: Eastern WA
Originally Posted by petie
When the compressor comes on it will draw more power from the engine which will cause the motor idle to go down.
On the excessive cycling, a low charge will cause that. However, since the compressor operation is controlled by low pressure, and because pressure and temperature are related, a low fan speed and/or operation on a cool day will increase the frequency of cycling. Always evaluate A/C operation with the fan on high, system on max with the windows down, engine speed at about 1,500 RPM (vehicle is parked), and ideally a warm day.
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You are right about the ECM detecting the idle speed change and it will adjust for it but it will cause the the engine RPM to drop for an instant when the comp. comes on - especially on 4 bangers - which would seem like a stall.
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From: utah
thanks yall, i will take my icv off, hopfully that is not that hard or complex to do and clean it up. i did already check my r-134 freon charge. and its full. so i suspect maybe an icv or something else
Posting Guru
Joined: Jul 2003
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From: Alvin, Texas.
If you've got that "click...click...click" from the compressor/compressor clutch, the coil is going bye-bye.
Been there, done that. $90ish and an hour of labor--let the tech reshim the coil or you destroy one precious v-belt--not a good thing, so I sat and watched.
As I have said before, almost all A/C issues are relay, switch, or coil related. If you can't find a leak--should be semi-obvious to find goop along the AC lines--that's not the issue.
My mechanic/salesman (yes, he's a stealer) deals with loads of PI CVics and they have that issue as well. He guessed right on mine, but only to back me up when I got mad that the AC and defroster were the only USELESS things on my truck at the time....
Been there, done that. $90ish and an hour of labor--let the tech reshim the coil or you destroy one precious v-belt--not a good thing, so I sat and watched.
As I have said before, almost all A/C issues are relay, switch, or coil related. If you can't find a leak--should be semi-obvious to find goop along the AC lines--that's not the issue.
My mechanic/salesman (yes, he's a stealer) deals with loads of PI CVics and they have that issue as well. He guessed right on mine, but only to back me up when I got mad that the AC and defroster were the only USELESS things on my truck at the time....
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Domestic_Nuwbee
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Dec 22, 2010 11:41 PM
