So I installed a Fuel Pump kit the other day and now the car seems to run leaner.... I also noticed that now if I turn the AC on, the car Shoots up in revs up to about 1200-1500 and then drops back down to normal....

I checked for a Boost leak but nothing... I'm kinda of stump. So has is there anyone else out there who's car became leaner after the pump? Car runs great no Knock just leaner. How lean?

Well my Wideband use to peg out at 11:1 AFR and then reads "- - -"(Version 1 AEM Wideband) now that means It's Beyond 11:1.

After the pump install I'm roughly sitting at 11:3-11:7 to11:7-:12.1 6000+ RPM. I'm not sure what the tune is set for but I'm just not use to seeing numbers with WOT other than 11:1-11:3 AFR before the Pump install.

 

No one?

 

What kit did you install?

 

My RPM's jump up as well when the condenser kicks in.
I did fuel pump and tune at the same time so I'm not sure if a fuel pump would cause you to lean out.

I would check the hoses to make sure they are not kinked or bent.

 

I used a UR Kit with a E85 Hose..... Same results.... then changed it out with Cobb's Kit (Evo 8/9 Sock).... same result.

I checked the lines at lease 5 times to be sure none of the hoses were kinked or ripped or anything to cause it to run lean..

The crazy part is when I logged the car there's no knock whatsoever. I'm beggining to think it may be the relays... I get them tomorrow from the dealer so If all else fails I'm not sure other than to just richen the map I have.

 

What did your IDC do before/after? Go up or down?

Which fuel pump are you using and from where?

 

I never logged or checked the IDC......

1) Ultimate Racing 255 Kit replaced the Clear Slinky with a E85 Compatible Hose (Brand New)

2) Cobb with Walboro 255 Brand new.