Moaning noise and stutter just off idle

[fngearhead]

I dumped a can of BG 44K in the tank the other day and since then I've been getting a sort of hollow moaning noise just off idle for a couple seconds. Also, when cold, the engine sutters off idle a few times till it warms up. Its had cold start issues since I got it, but this seems different. I had it aligned the other day and the tech just happened to mention that my hill holder was sticking and causing the noise. That was just his 2 cents since I didn't ask about the noise. Any ideas? I'm taking this car to Alaska for the summer, so hope to get it figured out fairly soon.

Brian