When I start my car up it makes almost a moaning noise then it will keep making it randomly, normally it's when my foot lets off the gas and when I put my brakes on. If I put it in park or sit too long at a light it will make that noise then a higher pitched noise then die. While making that noise my RPMs way up and then back down until my car completely Dies
My car has 175000 miles.
My car has an automatic transmission.
Hi there. From the description you have provided your vehicle’s moaning noise and intermittent stalling problem could be any number of things. It could be a failed alternator diode making the moaning noise and affecting the idle.
A failed alternator diode(s) allows voltage to flow both directions or no flow at all resulting in noise heard and erratic electrical operation. It could be a faulty idle air control valve. The idle air control valve can make noise and would account for the erratic idle and sporadic dying. It could be an accessory component, such as an A/C compressor, serpentine belt tensioner, or idler pulley, power steering pump making noise and placing undo load on the engine at idle. If you would like to have this done, a certified professional from YourMechanic can come to your car’s location to diagnose the noise and stalling issue.
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