So lads...

I got all my boost leaks under control. My boost gauge won't calibrate properly (currently) so... I have no info on that.

I installed the DW 301 pump. I can't hear it at all inside the car. Outside the car, its definitely noticeable, but quieter than my previous Walbro (though on another car).

My question... the car has a bit of a stutter (almost like a misfire or a boost leak (sigh)) every now and again under high load. Not always. My wideband AFR gauge is into the 10's now (not tuned) and I'm wondering if it's just because the car is running so rich?

The only other thing I can think of is maybe the O-rings on the pump? I re-used the OEM plastic spacer and the OEM double o ring, and then the black rubber thing that goes under the pump between the snap on plastic housing and the pump. I changed the fuel sock (filter) to the new one that came with the DW 301. Should I have added more O rings?

 

having your car run that rich is definately not good. you need to get a tune asap

 

I know... aside from running pig rich from the factory, I was surprised to see how rich the car ran by just adding the fuel pump.

Only mods I have are TBE with test pipe, UICP, LICP, and open cone filter. Anyway... hopefully (well not hopefully, but you know...) its simply a matter of tuning the car properly. All I'm really waiting on is getting my boost gauge setup properly.

It also isn't helping matters that the previous owner ran a CEL "delete" on the car. So it doesn't throw codes? and I don't have a cable to log yet.

 

Anyone else have any input on that?

 

Seems to me that you have the pump installed correctly. If you were having an issue with the seal between the pump and the assembly, you would be running lean, not rich.

I'd be interested to see what your fuel pressure is doing in this situation.

 

yeah my friend with an sti has had his 300 pump installed for about 3 months and his is doing fine.

i would check to see if your car spikes lean really fast when your car stumbles. that should tell you something is wrong in the air/fuel area and not a sensor or ignition. good luck.

 

Yeah... I actually am in the same boat. I have an underhood gauge leftover from my Evo 5... I wonder if I can just plumb it in to the stock FPR?

The pump is amazing though... you can't hear it at all inside the car. (which is exactly what I wanted). The install was simple, and the directions clear.

I need to get the car in for a tune, and we'll find out more info... I'm suspecting that the pump is functioning as is though.