Rich coming off the gas issue / PRC Valve Vacuum Routing on PG Manifold

I've been having this strange problem where when I let my foot off of the gas, the car wants to go real rich (10.0 afr) and then lean like it should.

If I am at partial throttle and come up to a stop and just push the clutch in, the car will go lean (like it is supposed to on decel) and then jump to 10.0 afr's for a good second and then to 15.1 (which is normal for me). At the point where it goes super rich, it wants to stumble and die and them may return to normal once the second or so passes...

It's very strange and only occurred after I decided to recirculate my BOV (yes I reset the ECU). My theory is that while having the MAF on the cold side, the intake readings are less sensitive to small things wrong with the car due to the MAF constantly getting a solid reading.

Since the MAF is back on the intake side, it seems to be picking up some issues that the MAF relocation would not have recognized...

My list of possible things wrong...

1) PRC valve is routed incorrectly on the PG intake manifold/vacuum leak
2) Leak in the recirculation fitting somewhere
3) DSM AFC map is taking a s***
4) My car wants to retire

List of mods:

-FMIC w/ Recir. HKS BOV
-PG intake manifold
-Full exhaust turbo-back
-Weapon R intake
-Battery in trunk to fit IC piping

AND...

I was getting on it a little bit to see how the AFR's looked and they were in the mid-13's low 14's!!! I am not sure if the ECU is still attempting to reconfigure itself or if the SS AFC map took a s***.


Any insight? Thanks in advance!

Ok so I just double checked my recirculation fittings and everything is tight and does not leak..

I will check the bov itself tomorrow and make sure when I put the recirculation fitting in the piston is tight against the seal.

I played with the PRC valve a little and just left it hooked up to the vacuum source and the fuel regulator/sensor. Same story with the rich off the throttle condition!

have you recalibrated your wb

Thanks for the reply. I have an AEM wideband and it seems to work fine. Supposedly the AEM does not need to be re-calibrated.. However I may be wrong.

When the rich condition occurs, the car stumbles and attempts to stall...

What happens is it goes lean (injectors shut down) like it is supposed to on decel and then goes super rich for a sec (10.0) and attempts to die --> Then it returns to normal 14.8-15.1

I checked my vacuum and it is strong at 23 inches.

I am not sure what else is could be at this point. I was thinking either a sensor is on it's way out or the SS AFC is out of whack somehow.