hey guys !

ive ran into to few fuel pump problems this past week..i wanted to upgrade my stock 8 pump to walboro 255... after putting it in my car would start and run very rough ..20.0 A/f at idling and when you start taking off car just dies..so i put in evo9 pump and car starts and drives but runs very lean! especially 2k-3k rpms

any ideas?? my mods are basically all the bolt ons (FML,piping, full exhaust, exhaust mani, hard piping,cat delete, hks bov etc..)

 

sounds like it was installed incorrectly. do you have the rubber grommit on the high pressure side of the fuel pump installed correct?

 

yeah i follow the guide on how to install a fuel pump

 

If I were you I would rechecked everything.

 

everything seems to be fine ... would it be one of the relays not working properly ??

 

just put back my stock pump and car is back to how it was ....

 

bump

 

Where did you buy the fuel pump? Not unheard of to have a bad one. Went thru a couple Walbro 255s on my DSM. Sent them back and they were bad. Took the third one to be right.

 

Just to double check what KevinD said, there is a small white plastic spacer where the pump inserts into the housing located on the pump discharge nozzle.
This needs to be swapped as well as the black rubber boot, if this is missed the pump discharge goes too far into the housing and causes fuelling issues.