i have a walbro 255 installed ran perfect. when to put in the walbro 400 seeded nicely, didnt hit any wires nothing.

went to start it up n it idles nices but the A/F was 10.0-11.3 i think it was that i need a FPR. So i went out and bought one. started the car n the FPR gadge goes from 0 PSI to about 5 PSI when running

so this made me think i had not correctly installed the walbro 400 right. unstilled it and put the walbro 255 in. Idles 10.0-11.3 n FPR reads 0-5 PSI im about to but a bullet threw my car!

only thing i could possibly think might be the problem is that the blue n black wire whiling pulling out the 255 they came off but i put them back in the clip and they seem to be fine

anyone have any idea what might be wrong! just makes no sense i modd the fuel pump housing n then put the 400 in then doesnt work so i put in the 255 again n now that doesn't work when it just did!

Here is a Video of what it is doing
http://www.youtube.com/watch?v=5UEs1...1&feature=plcp

 

How is the factory black seal at the top? Do you still have the white spacer?

 

Your fpr is not being overrun. You'll want to follow the instructions in this thread.
https://www.evolutionm.net/forums/ev...ould-know.html

Figured i'd add some to this. Did you try driving? If not give it a shot. Did the afr's fall back in line? If so then it is probably the siphon tube needing to be opened up a bit. The additional fuel flow may be backing up at that point. Why it didn't go back to normal when you put the 255 back, I couldn't say.

 

I don't think that's it. If its doing it with the 255 then its definitely not this.

 

I did a little ninja editing to explain my thinking.

To the OP, what modifications to the fuel pump housing were necessary to run the 400lph pump?

 

https://www.evolutionm.net/forums/ev...ification.html

 

Thanks, seems pretty straight forward.
If there were damage done to the pump wiring i could see the pump not working, but not over pumping.

Has the fpr been taken through it's range of opperation?

 

The OP should step away from the car for a couple hours, take a breather, clear his mind, and then retrace his steps. That's where is answer will be.

 

Yes this always works for me when I'm frustrated and in a bind.

 

i did that. i retraced my steps. found nothing.. took the 400 out n put the 255 in. then took that out n double cheacked the 400 was in correctly. same problem. so now the car idles rich 10.0-11.3 n doesnt move on both fuel pumps and the fpr reads 5psi

 

What kind of fpr do you have?

 

aeromotive

 

put a video up of what it is doing. it also was doing this with the 255 fuel pump. the walbro 400 is in the car with this video

 

Are you sure that gauge is reading correctly? I dont even know if its possible for the car to run with that low of a fuel pressure. Maybe if I have time this weekend Ill turn my regulator down to 5psi to see if it runs.

 

that a/f is reading right positive