Gen 1 running rich

L0wLif3

Registered
I bought a built 99 all motor busa a few years ago and the for the past year its been running rich. At first it just took a little extra throttle to start but now it needs to be wide open and needs the idle adjuster to be on just to idle when its hot. I noticed the plugs were fouled (all evenly) so i did what every back yard mechanic would do, start throwing parts at it. After a new air temp sensor, boost sensor, coils, set of plugs and all the connections checked I'm fresh out of ideas. the only other things i can think of is the bosch 280160237 fuel reg thats on it but its in the return line. When a fuel reg goes bad it lets more fuel in right? Which would mean the fuel pressure in the rail would be dropping not increasing. If I'm wrong let me know. I would have bought a new one but it seems to be discontinued and i cant fine any other fuel regs with no return and a boost port that goes up to 44psi/3bar to try. The only other thing i can think of is maybe the tune? It has a power commander v thats been dynoed. It ran and idled mint when i bought it which is why i never thought it could be the tune but idk where else to look. If any of you guys have any insight id be pretty excited about it, thanks.

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Do you have a copy of the map saved? Suck what the bike is currently running out and compare it to the saved copy.
I have seen them be the same. but RESENDING the saved copy has cleared up issues more then once
so maybe then do that....can't hurt anything
 
is there a plug in the middle aluminum colored part in the fuel rail?
I see two blue ones and a middle silver colored one
that would be "the best" place to check fuel pressure
or the feed line to the rail

the return line is not correct
the blue is fuel in and return the silver just connects the rail so i would have to check between the pump and the rail. ill see if i can find what psi the fuel pump i have should be at and check it out thanks
 
After a long wait for the right fittings to come in i was able to check the fuel pressure. I'm getting a little over 4 bar (checked at the feed line). The reg i have in the return line is a 3bar/44psi reg that they don't make anymore. So i cant replace it. What are my options? Is there a reg out there i can replace it with? Do i need to change my fuel system a bit?

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Is that 62 lb running? The pressure will spike a bit when you first shut it off.
 
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