fuel pressure regulator

I just finished a 12K check on my bike and while putting it back together I could not find the vacuum line that attaches to the fuel pressure regulator on the tank. It is running fine with out it. My question is where is the other end of the line attached at? :???: also there are 2 connectors that don't attach to anything, they are coming off the wire harness on the right side just aft oft he engine.

I just finished a 12K check on my bike and while putting it back together I could not find the vacuum line that attaches to the fuel pressure regulator on the tank. It is running fine with out it. My question is where is the other end of the line attached at? :???: also there are 2 connectors that don't attach to anything, they are coming off the wire harness on the right side just aft oft he engine.

[ctballos]

cesseltine,

I had my tank off the other day and noticed a 1/8" or so male fitting on the right fuel line quick connect. It did not seem to have a vacuum line attached nor could I find a loose hose anywhere. I don't know for sure either but I hope someone jumps in and tells us it is supposed to be that way.

ctballos

[ctballos]

cesseltine,

I had my tank off the other day and noticed a 1/8" or so male fitting on the right fuel line quick connect. It did not seem to have a vacuum line attached nor could I find a loose hose anywhere. I don't know for sure either but I hope someone jumps in and tells us it is supposed to be that way.

ctballos

My '04 Sprint ST did not have a hose on the fuel pressure regulator either. Noticed it when I changed the fuel fittings and couldn't find anything. There is a hose on the LH of the eirbox that has a blanking plug if I remember. The 2002+ factory manual doesn't mention it. Runs fine with out it.

The spare electrical connectors were there too. My guess was that they were for the injector etc on the non-existent 4th cylinder since the harness is used on 4 cyl models?

Phil

My '04 Sprint ST did not have a hose on the fuel pressure regulator either. Noticed it when I changed the fuel fittings and couldn't find anything. There is a hose on the LH of the eirbox that has a blanking plug if I remember. The 2002+ factory manual doesn't mention it. Runs fine with out it.

The spare electrical connectors were there too. My guess was that they were for the injector etc on the non-existent 4th cylinder since the harness is used on 4 cyl models?

Phil

thanks for the answer, I just recieved my factory manual and it doesn't show it anywere, yet it still calls for it to be disconnected when replacing the regulator.

thanks for the answer, I just recieved my factory manual and it doesn't show it anywere, yet it still calls for it to be disconnected when replacing the regulator.

[yerguy]

On the right underside of the air cleaner, you'll find 2 fittings, one large, one small. The large one is NOT open, but the little one is.

This hose connects between this small fitting and the connector on the fuel pressure regulator. This is used as an atmoshperic/barometric feedback for the pressure regulator. The reason it is often disconnected, or lost is it usually gets knocked off during the wrestling match to get the tank back in place. If you've ever done this yourself, you know what I'm talking about.

As mentioned, it has little effect because the pressure regulator is open to ambient air so it still is "reading" barometric pressure, minus what ever slight increase might be within the air cleaner airbox at speed.

The main barometric sensor is the Bosch electrical connection with the locking wire clip on the right rear of the airbox, so a disconneted hose has little effect. You'll find mention of this in the factory manual, chapt 9, pages 115-116.

Hope this helps,

The ol' windbag,
Dan'l
So. Calif.

[ This message was edited by: yerguy on 2004-10-11 14:22 ]

Dan'l, thank you for that explanation. I'll have to look again for the hose, next time the tank is off.

Phil