I was recently having issues with a P0507 code (RPM Higher Than Expected).
My idle was around 900-1000 RPM; my only mods were an ADD W1 Dual Inlet Catch Can and Stillen Intake.
Cleared the code, it would return like clockwork. When I turned the AC on the idle would drop to 650-700 RPM but AC off idle would remain around 900-1000 RPM. Well off the typical idle of around 600-700 RPM.
I could hear a vacuum leak but couldn’t locate it anywhere. I tried spraying the vacuum hoses with WD40 hoping to identify the leak, I couldn’t find anything. I went old school and blew cigar smoke into one of the vacuum lines hoping to find something, I couldn’t find anything.
Finally at my wits end, I decided to try to rule out the catch can, so I disconnected the vacuum lines and installed the factory lines. Fired the car back up and boom, 650 RPM rock solid idle.
So the issue is the catch can, I examine it and couldn’t find any issues.
I took off the vacuum lines and low and behold, the check valves were no longer functioning. The bearings in the valves broke away.
This is with the ADD W1 Dual Inlet Catch Can v3.3. So if you’re experiencing a vacuum leak, or have a higher than normal idle, check your catch can’s check valves. I have reported the issue and ordered some stronger check valves.
Catch can was ordered on May 4, 2019 so less than a month for check valve failure.
And yes, the check valves were installed the correct way with the arrows away from the catch can as the directions state.
My idle was around 900-1000 RPM; my only mods were an ADD W1 Dual Inlet Catch Can and Stillen Intake.
Cleared the code, it would return like clockwork. When I turned the AC on the idle would drop to 650-700 RPM but AC off idle would remain around 900-1000 RPM. Well off the typical idle of around 600-700 RPM.
I could hear a vacuum leak but couldn’t locate it anywhere. I tried spraying the vacuum hoses with WD40 hoping to identify the leak, I couldn’t find anything. I went old school and blew cigar smoke into one of the vacuum lines hoping to find something, I couldn’t find anything.
Finally at my wits end, I decided to try to rule out the catch can, so I disconnected the vacuum lines and installed the factory lines. Fired the car back up and boom, 650 RPM rock solid idle.
So the issue is the catch can, I examine it and couldn’t find any issues.
I took off the vacuum lines and low and behold, the check valves were no longer functioning. The bearings in the valves broke away.
This is with the ADD W1 Dual Inlet Catch Can v3.3. So if you’re experiencing a vacuum leak, or have a higher than normal idle, check your catch can’s check valves. I have reported the issue and ordered some stronger check valves.
Catch can was ordered on May 4, 2019 so less than a month for check valve failure.
And yes, the check valves were installed the correct way with the arrows away from the catch can as the directions state.
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