LB7: Rail pressure

[2500HeavyDuty]

Is there a way to adjust my rail pressure at idle to make my truck idle smoother?

my actual rail pressure is 7kpsi, but my desired is 4931psi.

my commanded FPR current is 1482mA and desired is 1491mA.

and FPR commanded is 50.2%. umm any ideas?

 

[2500HeavyDuty]

my rail pressure also drops down to 5kpsi in drive, with my foot on the brake stopped.

 

[MaxPowerLB7]

Only have a 2004 file to look at here at work but in table B1010 i would think you could lower the values slightly in the top couple cells and see how that works?

 

[Mike]

my rail pressure also drops down to 5kpsi in drive, with my foot on the brake stopped.

Is this not normal?

 

[Mike]

b1010 as mentioned or try fca duty cycle.

 

[tinman22]

that current level sounds high from logs I Took of my buddys 01. his commanded and desired current is more around 1200 Ma. and his pressure is in the 4K range. from my limited knowledge i'd say something is a little off.

 

[Mike]

Wouldn't a higher number cause a lower amount of fuel? A lower number basically makes the duty cycle go towards 0 and a higher number will achieve a higher duty cycle. 0 duty cylce, valve moves to allow more fuel.

 

[LarryJewell]

Only have a 2004 file to look at here at work but in table B1010 i would think you could lower the values slightly in the top couple cells and see how that works?

Actually try raising the values by "50" in the first three cells, if that doesnt get it where you want it, start bumping the same 3 cells by "5" until you get it where you want it.

Lowering the values will increase the rail pressure as Mike said.

 

[2500HeavyDuty]

ill give it a try, its nothing i can change while idling ?

im gonna have to flash and test and flash over again till its fixed?

 

[JOHNBOY]

ill give it a try, its nothing i can change while idling ?

im gonna have to flash and test and flash over again till its fixed?

Correct. Flash, Test, Flash again. It sounds like your FRPR migh be getting sticky watch your Desired RP vs. Actual RP at Idle. If your actual is higher than your FRPR is sticking.

As for programing for a smoother idle lowering your desired rail pressure can make a big difference. For me it really helped smooth thing out at idle. I am down to 4000 at idle with 5* MINJ Timing. Smooth and suprisingly quiet. I not sure if this work as good for you as it did me. My motor is far from stock. But it is worth a shot.

 

[2500HeavyDuty]

Well i did some changing to the RP at idle, it doesn't make that awful noise as much anymore, needs some more tweaking, but definitely alot better than before. my RP at idle is now between 4.9k and 5k, i mess with it some more to try and get the tackin noise completely gone

 

[MaxPowerLB7]

Actually try raising the values by "50" in the first three cells, if that doesnt get it where you want it, start bumping the same 3 cells by "5" until you get it where you want it.

Lowering the values will increase the rail pressure as Mike said.

Ha Ha ya thats what i meant to say
Good to see its workin out for you. I've often thought about putting an lbz pump or reg in, but two lb7 pumps would probably work pretty good too.

 

[2500HeavyDuty]

yeah i love it now, nice and quiet, even when its cold. idles real smooth too

 

[NelsonDiesel]

thanks for the info guys. i will be messing with mine today, hopefully.

 

[NelsonDiesel]

Did you edit just the B1010 table?

I added 50 to my first three rows as mentioned then installed, redid it....yada yada..... i started at 12000 psi at idle and i am now down to 8000 - 9000 but i am almost at 1500 in that table.

Can you post your b1010 table ?


is there something else i can edit to pull the pressure down?

 

[LarryJewell]

every truck is a little different, keep adjusting a little at a time, you have already said that its coming down, so your going int he right direction.

 

[NelsonDiesel]

every truck is a little different, keep adjusting a little at a time, you have already said that its coming down, so your going int he right direction.

cool, i just didn't wanna go too far. Don't see how....

another question.... i have been adjusting the first three, now the first one is at 1500 so i will be adjusting the 2nd and 3rd only now but come to the 4th there is a pretty big drop. Do i want to blend?

 

[NelsonDiesel]

all better !!!

Adjust the first 3 rows means adjust the first three rows !!!

i "assumed" 1500 was the max so i adjust the next 3 rows.... nope. When i had 3 rows of 1500 and no more changes.... i decided to do as told.... i started with 75 for the first three rows. That brought it to 5100 at idle. A few more times and we are sitting at 4900.

Thank you, no more clackity clackity

 

[LarryJewell]

My first cell is set at 1600, my idle is right at 4950

 

[NelsonDiesel]

i have a lopey idle. having looked into it further because i like it.... do you guys have that? Did i screw something up