Carnifex

iTrader: (2)

Just installed the WTF walbro 450 pump kit. This replaced my AEM 1220 pump which was a direct fit drop in pump. Looking at my fuel pressure reading from when the AEM was installed it took a long time for the pressure to bled off after the engine shutdown , a few minutes atleast. After the Walbro install the pressure bleeds completely off in about 20-30 seconds. To make sure nothing blew off in-tank i removed the entire assembly again and verified all hoses were attached and the venturi was down all the way in the seat. O-rings also look to be right where they should be. Does anyone else see the same thing with the walbro pump? Only thing i could find is that the 450 may not have an internal check valve and my theory is the pressure is bleeding back through the pump and the larger 5/64 venturi hole. Car starts every time ( hot and cold) and the fuel pressure is exactly the same at idle. Verified no leaks at the inline filter , sensor port, fuel lines and just in case the rail .

BTW the WTF 450 kit is really nice. install instructions were great. For those wondering the AEM pump was also a good pump, but my fuel demands will be going up soon. If you are on FBO this is a great pump for sure for those that want an exact drop in.