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Hearing strange noises. Help?

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#1
So, the biggest thing I have is where the car sounds like it's about to stall as it slows down. I added a video so you can hear it. The car is in neutral, and revs are at idle as it slows to a stop. The sound begins at about 15 mph or so.. It also occurs when I turn on the car, and disappears as I increase revs.

Also, in cylinder 4 I'm getting some negative corrections. No clue what they mean so some info would be nice. It doesn't happen on WOT, but when I'm just cruising and not really paying attention to my AP. I'm using a Cobb Stage 1 93 octane tune, my OAR is at -1.00. My car has 9100 miles on it.

Finally, here's a fun glitch when you reset the gauge numbers. Not really much of a concern.
 


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#2
So, the biggest thing I have is where the car sounds like it's about to stall as it slows down. I added a video so you can hear it. The car is in neutral, and revs are at idle as it slows to a stop. The sound begins at about 15 mph or so.. It also occurs when I turn on the car, and disappears as I increase revs.

Also, in cylinder 4 I'm getting some negative corrections. No clue what they mean so some info would be nice. It doesn't happen on WOT, but when I'm just cruising and not really paying attention to my AP. I'm using a Cobb Stage 1 93 octane tune, my OAR is at -1.00. My car has 9100 miles on it.

Finally, here's a fun glitch when you reset the gauge numbers. Not really much of a concern.
stuttering issue may be evap, 02, or if its happening all the time maybe a vacuum leak. As far as the negative corrections if its not happening on wot pulls I wouldn't worry about it. Wot is when the engine is on the most load and will absolutely apply negative corrections to timing if there is an issue. cruising around it could be something called ghost knock. Which is to say cruising around maybe something is causing a noise which the knock sensor is picking up near cylinder four. Test that by adding a gallon of E85 on your next fill up and see if it goes away. if it does go away it's a tuning issue. If it doesn't you have ghost knock.
 


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Thread Starter #3
stuttering issue may be evap, 02, or if its happening all the time maybe a vacuum leak. As far as the negative corrections if its not happening on wot pulls I wouldn't worry about it. Wot is when the engine is on the most load and will absolutely apply negative corrections to timing if there is an issue. cruising around it could be something called ghost knock. Which is to say cruising around maybe something is causing a noise which the knock sensor is picking up near cylinder four. Test that by adding a gallon of E85 on your next fill up and see if it goes away. if it does go away it's a tuning issue. If it doesn't you have ghost knock.
Thanks. It doesn't happen all the time, mostly when the AC is on and it's super hot out. I figured it might be something to do with my RMM, but I doubt it. Thanks for the advice!
 


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#4
Mine does the same thing btw, doing it with the ac on maybe because the compressor is putting a load on the engine when the rpms are trying to stabilize at idle. Just a thought, like I said happens to me but doesn’t stall or effect power at all.


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OP
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Thread Starter #5
Mine does the same thing btw, doing it with the ac on maybe because the compressor is putting a load on the engine when the rpms are trying to stabilize at idle. Just a thought, like I said happens to me but doesn’t stall or effect power at all.


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Yeah I thought it might have something to do with that. The sound is just so jarring, like my friends ask me if it's supposed to make that noise and I just kinda say I guess.
 


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