E-Bodies.org Cuda Challenger Forum

Technical Shop => Engine, Transmission & Rear End => Modern Hemi Swaps => Topic started by: anlauto on August 07, 2022, 02:24:44 PM

Title: GEN III Hemi question ???
Post by: anlauto on August 07, 2022, 02:24:44 PM
So on my crate motor there's an open tube on the intake....I thought it was just a stanchion to support something on the new cars, but then somebody asked me at a cruise night why it wasn't plugged off....So I checked and sure enough it is open to the intake....

Started looking at pictures of new cars, and something is hooked to it....something my crate motor didn't have...My car runs fine, but could this not be considered a vacuum leak ?  Every once and a while I hear a whistle sound when accelerating ???? :looney: could it be that ? Should I cap it off ?

Does anybody know what it could be ?
Title: Re: GEN III Hemi question ???
Post by: HP_Cuda on August 08, 2022, 01:42:01 PM

Best guess is PCV:

https://www.cargurus.com/Cars/Discussion-t30906_ds798527
Title: Re: GEN III Hemi question ???
Post by: Dmod1974 on August 08, 2022, 03:33:12 PM
Sure looks like the EVAP canister purge line port to me.
Title: Re: GEN III Hemi question ???
Post by: anlauto on August 08, 2022, 04:05:36 PM
So does it matter if it's open, or should I plug it off ?
Title: Re: GEN III Hemi question ???
Post by: Dmod1974 on August 08, 2022, 04:13:17 PM
Plug it unless you don't mind a large vacuum leak.
Title: Re: GEN III Hemi question ???
Post by: anlauto on August 08, 2022, 07:27:22 PM
Quote from: Dmod1974 on August 08, 2022, 04:13:17 PM
Plug it unless you don't mind a large vacuum leak.
That's kinda what I was thinking, but the car seems to run just fine  :clueless:  I'll plug it and see if there's any change.... :handshake:
Title: Re: GEN III Hemi question ???
Post by: Dmod1974 on August 08, 2022, 07:48:17 PM
It'll probably compensate for it to a point in closed loop mode, but at WOT when it goes into open loop you risk running too lean at the worst possible time.  If it doesn't suck air at idle, my guess is it is "ported" vacuum only and why you hear hissing when driving since the throttle is opened then. 
Title: Re: GEN III Hemi question ???
Post by: 1973Cuda on August 09, 2022, 04:56:51 AM
Mine is plugged.
Title: Re: GEN III Hemi question ???
Post by: Mybrothers70 on August 09, 2022, 07:28:16 AM
Mine is plugged on my Gen3 as well. :yes: