So this morning I thought my car was backfiring slightly just after leaving the house. This afternoon and on the way home from work I could hear what sounded like a squeak from under the hood and what seemed like a split second drop in power. It made the noise accelerating and decelerating at speeds under 40 mph. My DAM has dropped from 1.0 to .83 I have a Prodrive shorty catless DP with a gutted stock OEM midpipe. The aircleaner is a Subaru panel filter. Running Cobb OTS stage 2 tune. The car has to be under load or decelerating to make the noise. I haven't been able to locate anything loose under the hood. Any ideas? Thnx
Thank you I'll check to see if I hear the noise with the AC off. I was not going to try that in the heat yesterday. I was near empty so I got a full tank. I'll see if that fixes the problem today.
Guarantee that sound is probably your AC clutch. Wanna know how i know... Cause mine is doing the same thing. You can try and tighten the belt but be careful cause the plastic piece strips easy...
Make sure you reset the ECU on the new tank. Should be able to see the AM climb back up and stay where it is supposed to.
It's the AC It is the A/C. It Squeaks and clunks. The clunk is sort of like a pop and is what i was thinking was the backfire. Maybe with the high heat there is too much pressure in the A/C system. The car only has 27,000 miles on it so I hope the compressor is not having issues. I'll bleed the system a little and see what happens. As for the .83 DAM I'll chock it up to the HOT weather and that possibly the anti knock system is picking up the noise from the A/C clutch and is backing off the timing a little. I'll hold off on resetting the ECU. I'd rather correct the A/C issue and see what happens. If the engine needs the timing dialed back a little due to the weather I'd rather keep the engine happy and safe. Thanks to all that replied! I'll post any updates.
DAM has been moving around from .83 to 1.0. Seems heat and fuel level related. Still have the original fuel filter in it so I'll get that changed this weekend.
Man, just swing by and lets have a look see at what is happening. I have some time this weekend. Thanks again for giving the a hand the other day. I really appreciate it.
So I am a dumba** I forgot that I had added some refridgerant to get the A/C a little colder. Turns out that the system was overcharged and with the hot weather we have been having... I bled off a little gas and the squeak and knock went away!