So I just recently installed a Spectre air intake and for the first week it was doing good, but now it has been starting to make this weird vibrating noise when im not giving the truck any gas. It also rough idles, the rpms will shoot up and then drop down low. Im not sure what it is, I cleaned my MAFS but it did not help at all. However, when I unplugged the sensor it was idling fine until I started driving, then it started rough idling again. I know I "should've just done the gotts mod" but its a little late for that. Any help would be great, thanks everyone.

 

Are you getting any codes? Where the sensor plugs in flip it around. U might have that piece on backwards. Double check....Meaning flip the front to be the back.

 

make sure all vacuum hoses are connected and secure

 

Check all the vacuum lines, particularly the PCV line.
Have you inspected the Idle Air Control (IAC) valve?

 

Put the stock intake back on it and see how it runs.

 

I changed the IAC valve and the truck is running great, other than in Park it idles very high at 2,000 RPMS, and the check engine light is back on But the truck is running great.

 

What code got set?
High idle RPM could be a medium size vacuum leak.
Check the Throttle Position Sensor (TPS), too.