Base fuel pressure slowly drops while riding

[GXR1147]

New power numbers are 334/196 @ 15 lbs. Here's the only pic of the new stator I took out of the bike. And the video is from last year. It was only making 235hp at the time but it looks the same, only difference is now it has an ultra plenum set up on it. (And the boost gauge is now tied into 2 signal ports so it's not bouncing all around under vacuum anymore)

[ali123]

New power numbers are 334/196 @ 15 lbs. Here's the only pic of the new stator I took out of the bike. And the video is from last year. It was only making 235hp at the time but it looks the same, only difference is now it has an ultra plenum set up on it. (And the boost gauge is now tied into 2 signal ports so it's not bouncing all around under vacuum anymore)

View attachment 1580961

isn't that ultra plenum incredible?

[RansomT]

But the fuel pressure shouldn't move around that much due to a voltage change while not in boost. The pump should keep up with the FPR at just about any voltage while the injectors are not using up the fuel.

[GXR1147]

isn't that ultra plenum incredible?

Yes, no argument from me.

[GXR1147]

But the fuel pressure shouldn't move around that much due to a voltage change while not in boost. The pump should keep up with the FPR at just about any voltage while the injectors are not using up the fuel.

You're right, it should. But it didn't. I'm guessing it was an amperage issue. Unfortunately I have no way of testing the amp output of the stator. There were times when I would rev and see static pressure drop. But the point when the battery power was being consumed while the bike was running would show it not charging at all. As battery power drops, so does power to the pump. I'm taking it for a proper test drive today. I'll know for sure later.

[Hayabusa Wannabe]

Have you tested for short circuits?

[GXR1147]

Have you tested for short circuits?

Shorts on what? I've checked the fan, chassis/engine grounds ect.

[GXR1147]

It did ok on the test drive. Pressure did move a little though. Started out at 32psi cold. Saw a low of about 28-29 (hard to see while riding.) so I'm guessing there's still something going on. also got a -C13 code for IAP sensor. I only get it when I get into my higher boost levels. Not sure what's causing that. Frank replaced my little vent thing before the sensor because it got broke during winter work. Maybe the new one isn't venting enough?

[Hayabusa Wannabe]

Shorts on what? I've checked the fan, chassis/engine grounds ect.

Shorts anywhere in the system. The manual refers to it as "battery current leakage inspection". Set the ammeter to 20A or the highest scale. With the bike completely off put the ammeter between the negative cable and negative battery terminal. Change the scale to (examples which may not match yours) .2A, .02A, etc. until it provides a valid reading. It should be below 3.0 mA (.003 A) per the manual. If the current is significantly higher than this pull fuses until the current drops. That fuse IDs the circuit with a short.

I was thinking that a cable could potentially have gotten nicked during the cable re-routing, introducing a short.

[GXR1147]

Shorts anywhere in the system. The manual refers to it as "battery current leakage inspection". Set the ammeter to 20A or the highest scale. With the bike completely off put the ammeter between the negative cable and negative battery terminal. Change the scale to (examples which may not match yours) .2A, .02A, etc. until it provides a valid reading. It should be below 3.0 mA (.003 A) per the manual. If the current is significantly higher than this pull fuses until the current drops. That fuse IDs the circuit with a short.

I was thinking that a cable could potentially have gotten nicked during the cable re-routing, introducing a short.

Very possible. I'll check it tomorrow when I get back to my garage. Ty

[POWERHOUSE]

. . . also got a -C13 code for IAP sensor. I only get it when I get into my higher boost levels. Not sure what's causing that. Frank replaced my little vent thing before the sensor because it got broke during winter work. Maybe the new one isn't venting enough?

Put another "T" in with another check valve, right next to the one I put in. See if that fixes it.

[GXR1147]

Put another "T" in with another check valve, right next to the one I put in. See if that fixes it.

Where do I get them? Got any links for amazon or anything? Only place I've seen them was in my stage 1 kit and you had them. What would I look up to find them? Is this something you've seen before?

[202mphbusa]

https://shop.advanceautoparts.com/p/dorman-help-vacuum-check-valve-universal-47149/5707110-P

[202mphbusa]

I had three at one point,,, then I reflashed my ECU so it don't care

[GXR1147]

I had three at one point,,, then I reflashed my ECU so it don't care

Haha, damn. I was under the impression that pressure can kill those sensors. Down side is now I feel like I have to ride around with a jumper wire and a 5mm Allen key in my pocket for when the FI light comes back on.

[GXR1147]

https://shop.advanceautoparts.com/p/dorman-help-vacuum-check-valve-universal-47149/5707110-P

I was also under the impression that the valve needs to vent pressure, not just a one way valve.

[202mphbusa]

one way valve vents the pressure, but the map needs accurate vaccum
Or send me the ECU and I can reflash it extending the map so no more error

[202mphbusa]

Haha, damn. I was under the impression that pressure can kill those sensors. .

22,000 miles since turboing this thing........mine would have been dead LONG ago
it has seen 30psi and still works

[GXR1147]

Shorts anywhere in the system. The manual refers to it as "battery current leakage inspection". Set the ammeter to 20A or the highest scale. With the bike completely off put the ammeter between the negative cable and negative battery terminal. Change the scale to (examples which may not match yours) .2A, .02A, etc. until it provides a valid reading. It should be below 3.0 mA (.003 A) per the manual. If the current is significantly higher than this pull fuses until the current drops. That fuse IDs the circuit with a short.

I was thinking that a cable could potentially have gotten nicked during the cable re-routing, introducing a short.

.001

[ali123]

u get this fixed yet?