still have a whistle/hum after regen valve - 986 Forum - The Community for Porsche Boxster & Cayman Owners

mipstien · 03-07-2016, 05:46 AM

I have the dreaded whistle from the evap system coming from the fuel fill area. I replaced the fuel vent and the regen valve but at speeds that are cruising with a constant rpm the hum comes on. does not do it during accel or coasting. It also seems to be doing it at nearly any rpm. 2k-4k common to be stuck at for any amount of time while driving and it will start to hum. It never does it at idle and it isn't nearly as annoying as it was before I replaced the regen valve.

There are no cel codes coming up and not even a possible fault showing up. everything is clean. The car is running currently better than it ever has, minus the embarrassing noise it makes from that area.

I don't want to just bandaid this sound I would prefer to figure it out.

mipstien · 03-09-2016, 04:59 AM

I'll bump this. Still a mystery.

boxxster · 03-09-2016, 05:53 AM

Is this the part you replaced already?

http://986forum.com/forums/general-discussions/30474-e-vap-noise-help.html

Mine does the same exact thing. I've never had a boxster before so I thought it was normal

mipstien · 03-09-2016, 07:08 AM

No this is the part I replaced. Although I did check the part that you are linking to. My noise only happens at cruise speeds not on accel or decel and not at idle either. When does yours make the noise?
[IMG]http://www.************************************************************************************.com/images/products/134346.jpg[/IMG]

EDIT: Picture just went derp and didn't show.

boxxster · 03-09-2016, 08:09 AM

Only makes it when I am holding a constant cruising rpm (2500-3k ish in my case). If I give it gas or let off it goes away. It seems like I need to be driving at a constant speed for at least 15 or 20 seconds before it comes on.

jpl2407 · 03-09-2016, 08:44 AM

I am curious as to what the outcome of this mystery noise may be as I have the same one, cruise a while .... noise occurs, lift off or accelerate a little, noise goes away.

mipstien · 03-09-2016, 10:22 AM

I am better off knowing others have this noise and I'm not alone. Doesn't change that I hope to figure the problem out.

I wonder if i shouldn't just get a fully working evap system and start changing parts out and see what happens. But I also don't want to spend all that money on something that may or may not be the final cause. There aren't a lot of places for the evap system to 'go bad' without throwing codes so at least I (we?) have that going for us.