Cleaned AFE, Got a WEIRD sound on startup.

[AndyMan]

Hey peeps,



I cleaned and re-oiled my AFE PG7 today. After remounting the filter to the Magnum Force housing, and starting the truck I had a really WEIRD thing happen...



First lemme lay down some background info. At 6 A. M. this morning, I cleaned the filter. About 10A. M. , I oiled the filter (sprayed it on pretty good... that may have been mistake #1). Mounted her back up about 3P. M. Drove the goat to Nashvegas about 4, which is roughly 30 miles from the house. I made it there and back with no problems.



Okay. . here's the weirdness. I turned the key. Windows down, A/C on. Waited for the light to go out (took about 2 secs). Turned key rest of the way, fired up the motor... released key. THEN, I heard a high pitched "psssshhhhht" sound. It sounded very much like a really high pitched turbo bark. It lasted about as long and a bark, and kinda rocked the truck up on the passenger side for a split sec.



Did I suck a glob of filter oil up in the turbo? Was it maybe just the A/C compressor kicking on?



Like I said, I made it to Nashville and back without a hitch, SO I'm inclined to believe it's fine. I just get a little hyper-sensitive after I make a change. Since you guys are my control group, I thought I'd bounce this one off of you.



Thanks for the help and input!

Andy

 

[Prairie Dog]

It was the A/C compressor - they tend to make a noise like that when they kick in at low RPMs. Don't worry, it's normal.

 

[BGiles]

My A/C compressor makes a loud Thump/Knock when it kicks in. So is this common?

Never heard the hiss noise, always had the windows up.



Brian

 

[AndyMan]

Outstanding! Thanks guys.



I might have heard it before... but I've never had the A\C on and Windows rolled down at the same time.



I can sleep now.

 

[rbattelle]

Originally posted by BGiles

My A/C compressor makes a loud Thump/Knock when it kicks in. So is this common?

Never heard the hiss noise, always had the windows up.



Brian

Yes. Sometimes mine sounds like someone whacked something under the hood with a large hammer, to the point I can actually feel the thump! I believe it's due to the large pressure difference when you first turn on the pump.



It's funny how we're getting back into spring and the same questions that came up last spring are cropping up again. Like just before winter we'll get into heater grids cycling, voltage drops, when to plug in, etc.

 

[Tony T.]

You'd think the bottom end of your motor just dropped out at times when the compressor engage's. The first time I heard it, was what the heck was that!:-laf Also get the belt "chirp" noise at time's when shutting down the motor. I think that only happens on the auto's though.

 

[BGiles]

Originally posted by rbattelle

It's funny how we're getting back into spring and the same questions that came up last spring are cropping up again. Like just before winter we'll get into heater grids cycling, voltage drops, when to plug in, etc.

Gotta love those "Seasonal Quirks & Questions"



I have had the truck for 5 months now and 11,000 miles, and I am just now starting to use the A/C.



Thanks,

Brian