I just got back from the dessert and my car has sat for about 4 months. I bumped it over a few times to get the oil moving and drove it to work the next day. That night I went to put in sun hyper force that I ordered. It seemed like it was working great I ran up and down the street with no problems. I went to make sure everything electrical worked and when I cut on the a/c I have this tapping noise that sounds like it is coming from the fuel injector/ intake area. It is kinda of a radom tapping but, only with the a/c on. I disconected the hyper force but, I still have the noise. I didn't get any engine codes except the p0300 one that has been there since I installed the hks 280 cams. I put stabil in the fuel before I left. I don't know if it was doing it before I installed the hyperforce I was riding around with the stereo on. Any ideas what this noise could be?

thanks,
anthony

 

Dirty lifter?

 

here is a good thread about the a/c and noise. https://www.evolutionm.net/forums/sh...ighlight=a%2Fc
i have the same noise when my a/c is on. the majority believe its the tob. next time you hear the noise push the clutch in. if the sound goes away its the tob.

 

Throw out bearings don't usually sound like what I would describe as tapping near the FI/intake area.

 

Thanks guys. Somehow I forgot the a/c part when I searched. I'm going to try it agian this morning.