85 GSL-se idle surge w/ac on
06-15-15, 08:34 AM
#1
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85 GSL-se idle surge w/ac on
I've read the idle surge posts here, but haven't seen this addressed. Idles fine until I turn on the ac.then it searches between 1000 and 2500 rpm. Back and forth every second. Will quit sometimes when I turn the fan to highest position. Stock se with cat converters and exhaust pump removed. Got to be ac related. Any ideas where to start on this? Thanks Guys.
06-15-15, 01:17 PM
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i'd start with the TPS, and then look at the Air Supply valve. i think that is the one that does the A/C idle up
06-15-15, 05:46 PM
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I don't have the surging problem with A/C on in my SE, but I don't get the "Idle Up" so it will stall sometimes with the A/C on. I've tried a new Air Supply Valve I got from a Forum Member but didn't help.
06-15-15, 09:14 PM
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Mine used to do the same when it got really warm under the hood. Be sure your cooling system is working well and your radiator especially is not clogged. Really annoying when at a stop light and the surging won't quit.
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06-16-15, 04:47 AM
#8
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Cooling system is fine. Thanks for the tip though.
06-18-15, 01:32 AM
#9
84SE-EGI helpy-helperton
Grotto107 - you've been around for 10 years and ONLY 87 posts? You have better control than the rest of us!
As to surging, it may seem related to A/C, but it's still the throttle body rods sticking and causing a feedback loop. The Air Control Valve and ACV Solenoid are the trigger for the surging to start, and then after that it's throttle body rods sticking that keep it going, trust me.
Follow the procedure for 'surging SE' and you'll get it sorted out. Don't assume it's the ACV just yet, as anything which causes the engine to speed up such as turning on A/C can act as a trigger for surging. Good luck,
As to surging, it may seem related to A/C, but it's still the throttle body rods sticking and causing a feedback loop. The Air Control Valve and ACV Solenoid are the trigger for the surging to start, and then after that it's throttle body rods sticking that keep it going, trust me.
Follow the procedure for 'surging SE' and you'll get it sorted out. Don't assume it's the ACV just yet, as anything which causes the engine to speed up such as turning on A/C can act as a trigger for surging. Good luck,
06-18-15, 03:57 AM
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Thanks LongDuck. That makes sense since I had sticking throttle body problems about 3 years ago. Car would stick at 2500 rpm. I'm at my beach place now with nowhere to work on the car. Will be home in 3 weeks or so and I'll tackle it then.
06-18-15, 07:06 PM
#11
84SE-EGI helpy-helperton
Well, a quick-fix would be to remove the 2x10mm chrome plated cap nuts that attach the airpipe to the throttle body and move it slightly out of the way. Spray some PB Blaster or other light oil onto the rods where the enter the TB inside the venturi's and that should alleviate the problem for awhile.
After you get home, remove the entire TB and oil it properly and let the oil soak in by leaving the TB on each side overnight to draw the oil in by gravity. That's lasted me for years doing it right, but I always end up having to oil them again once the surging starts to come back. Good luck,
After you get home, remove the entire TB and oil it properly and let the oil soak in by leaving the TB on each side overnight to draw the oil in by gravity. That's lasted me for years doing it right, but I always end up having to oil them again once the surging starts to come back. Good luck,
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