99 Civic -- Fluctuating idle, P0505, and fan issue
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99 Civic -- Fluctuating idle, P0505, and fan issue
I'm working on a 1999 Civic lx standard trans with a D16y7. The car is getting the P0505 code. Checked for vacuum leaks and all is good there. The idle fluctuates from 1000 to 2000 rpm. Idle fluctuation only happens when vehicle is warm. The idle goes back to normal when the fan kicks on and goes back to fluctuating when it kicks off. My question is can this be the ECT sensor causing the idle issue?
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Re: P0505 and fan issue
In the one thread about the possible causes for the P0505 code it does list an ECT as a possible cause. I was wondering if the ECT was causing it due to the motor changing idle with the fan turning on and off.
Found here:
https://honda-tech.com/forums/showth...ighlight=p0505
Found here:
https://honda-tech.com/forums/showth...ighlight=p0505
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Re: P0505 and fan issue
Rule out the IACV first like suggested. Then if the valve is good look closer at the ect.
The three wire IACV on those is on the throttle body
The three wire IACV on those is on the throttle body
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Re: P0505 and fan issue
Was able to work on the car today. Removed and cleaned the IACV. The CEL is gone but idle is still bouncing. I covered the port on the throttle body and the idle went down the 700. Guessing the IACV will need replacement.
#7
Re: P0505 and fan issue
1) Bleed cooling system.
2) Try to adjust the idle speed -- see diagram in FAQs sticky.
3) Test the TPS and the ECT sensor.
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Re: 99 Civic -- Fluctuating idle, P0505, and fan issue
Before cleaning the IACV I did unplug the connector on it and idle still did not change at all. That is what is making me lean towards the IACV being bad. I probably won't get to take another look at it until next week and will check the coolant system, etc.
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Re: 99 Civic -- Fluctuating idle, P0505, and fan issue
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Re: 99 Civic -- Fluctuating idle, P0505, and fan issue
I did the test with the idle fluctuation happening and idle did not change at all. Seems like the valve maybe possibly be stuck open? I covered the port on the throttle body that leads to the IACV and the car idled perfect.
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Re: 99 Civic -- Fluctuating idle, P0505, and fan issue
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01-22-2004 08:13 PM