Idle problems when letting off the gas NOT VENTING either

[DJ23GSX]

My problem is my idle but only after letting off the gas and coasting or stopping at a light. (I am not venting my bov either).It drops down to 400rpms and almost stalls. After a minute of fumbling it catches and idles normal. When i try to rev it up when its fumbling it kinda stumbles and then rev's like usual. I have checked for boost leaks and don't have any I have also changed my maf with a 2g one and still have the same problem. I've also tried way rich and way lean on my safc with no luck. About a month before this problem began i was a victim of a leaky weapon r afpr and i was sucking fuel through the vacuum line. What damage could this have done and could this be my problem? I am running a walbro 255 also with the stock fpr for now but i have run that problem free for over a year before the afpr accident. When the problem first happened i was getting an airflow sensor error on my logger. I have cleared the error and reset the ecu but still have this problem. I have noticed that its worse in the morning when its colder outside and my lights and heat are on. Also on the logger my battery volts are only around 12v when its stumbling.

Any info will help
Thanks

 

[OverboostXS]

255lph and a stock FPR is a bed setup as you probably know so this couldn't be in your favor at all about the idling problem. Replace your MAS with a properly working 1g MAS to make sure it is not the problem. Other then that work on getting a decent FPR.

 

[steve]

Check the Idle Position Switch, the Vehicle Speed Sensor, and the ISC. Anyone of these failing can cause the idle to sag in the ways you describe.

Steve

 

[DJ23GSX]

I have tried 2 different 2g maf's and a good working 1g maf and still the same problem. I know the stock fpr isn't helping but it ran great for over a year with the walbro 255 and ran good for a month after my afpr took a dump on me. I didn't change anything and this problem just popped up. Today i went up to +20%@1000rpms' on the safc and it seemed to help a ton. The rpm's hardly dip at all when coming to a stop but here's the catch my low fuel trim is maxed out trying to take fuel away. I didn't mention that my 2g maf has all of the honeycombs still in.