LB7: FPR Install Fun!!!

[paint94979]

Its not getting any better, no matter how I change the regulator table. Enough screwing with this....Im going to run an regular old LBZ reg and call it a day.

what is it doing? romping at constant RPM? mine does the same thing... do you run the lift pump all the time? my drastically improved with the lift pump always on

 

[TheBac]

lift pump always runs. It was a used LB7 regulator...which I now figure was not exactly in good used condition.

You know how it goes...if the part doesnt work out, try something else. I can always try to mod my OEM LB7 piece, but Id like the truck to be running until i get a chance to do it. That wont be for a while.

New windows for the house come in Monday....and the house/family takes precedence over the truck....always.

 

[sweetdiesel]

lift pump always runs. It was a used LB7 regulator...which I now figure was not exactly in good used condition.

.

you are altering B1010 table and logging regulator current correct?

At idle what is des rail and actual? Also what is you reg current at des VS Act? What is it at WOT?

You realize you are still probably going to have to modify something with the lbz reg.

What and how much have you changed and what exactly is the issue?

 

[fishsmith]

Tom I had my b1010 values raised to high and it would cause a surge when idling and sometimes going down the road. Lowered back down to 1600 1510 and 1450 in the first three columns and everything is good rail pressure is a hair high but no lopey idle also it didn't matter if my lift pump was on or not. Lift pump pushes 15psi as well

 

[TrentNell]

I dont think one can expect to get the same drivability with a modded regulator as you can with stock, the vary nature of how the mod is done pretty well makes it impossible IMOP, once modded the reg no longer has a progressive port , it goes from small then much bigger instantly . the choice is simple if you want to go fast there are certain comprimises . Mine has a slight surge at some points part throttle but it doesnt bother me a bit . If it starts to......... i just hammer down and it gets me thinking how much i love the extra fuel :rofl:

 

[TheBac]

I'll get on the logs. I know we didnt save any from teh dyno pulls, and I havent recorded any since. We lowered the values in B1010 to start at 1400 and go down from there, but it still surges pretty bad. Ive since tried lowering them slightly more to 1350, and smoothing the curve, but still no joy. RP was soemwhere in the 5000s at idle IIRC, and desired vs actual at speed is usually within 1000psi.

Mark thought it was probably a bad coil in the regulator. I tend to agree, since I bought it used, and also because I know Michael does exceptional work on these things....no way does he let a bad one get thru.

Its a 100 rpm surge at idle, but I can also feel it during steady cruise on the freeway. Worse when the engine is cold. Sorry Trent, but I find that unacceptable. I refuse to give up driveability just to go faster in the 1/4.

 

[TrentNell]

I'll get on the logs. I know we didnt save any from teh dyno pulls, and I havent recorded any since. We lowered the values in B1010 to start at 1400 and go down from there, but it still surges pretty bad. Ive since tried lowering them slightly more to 1350, and smoothing the curve, but still no joy. Mark thought it was a bad coil in the reg. I tend to agree, because I know Michael does exceptional work on these things.

Its a 100 rpm surge at idle, but I can also feel it during steady cruise on the freeway. Sorry Trent, but I find that unacceptable.

you should be raising the table not lowering it ( at least i had too ) , and yes my truck idles perfectly .

at idle my tables are at like 1750

 

[TheBac]

Raising it? Oh you have gotta be shitting me. Looks like I may have got some incorrect info somewheres.

Will fix and retry tomorrow after work.

 

[TrentNell]

Raising it? Oh you have gotta be shitting me. Looks like I may have got some incorrect info somewheres.

Will fix and retry tomorrow after work.

raising the # pulls/pushes the valve closed harder .......

 

[Dazedandconfused]

LLY is much easier

drain coolant.
Remove the black tube from the thermostat ( thermostat outlet)
Remove the upper intake that is on top of the egr valve
Remove the Mouthpiece


Now you have plenty of room !

Thats what I wanted to hear. I'm still trying to find out if mine is acting up just havent had time. Mine lopes/surges at idle however you want to say it.

 

[Turbotug]

I dont think one can expect to get the same drivability with a modded regulator as you can with stock, the vary nature of how the mod is done pretty well makes it impossible IMOP, once modded the reg no longer has a progressive port , it goes from small then much bigger instantly . the choice is simple if you want to go fast there are certain comprimises . Mine has a slight surge at some points part throttle but it doesnt bother me a bit . If it starts to......... i just hammer down and it gets me thinking how much i love the extra fuel :rofl:

The LB7 reg (mine atleast) doesn't really have much progression anyway. A thin slit to a rectangle, not like the triangular one photo'd in Relentless post. With the way this mod is done it shouldn't affect that area.

I have pics of mine virgin and mod'd. Thought I posted them before, but I can again for those that want a look.

 

[sweetdiesel]

raising the # pulls/pushes the valve closed harder .......

:rofl:Exactly Tom look at the table....Most if not all trucks use 0 at wot(stock)

Ilde rail should be around 6k iirc,You dont need to be on a dyno you can do it in the driveway

Adding numbers in at the most increments of 50 in the first 2 spots should be more than enough then smooth the 3rd number and you will be good to go.


here is a pid that has everthing you need to watch if you log it WE can tell you what you need to do.

A lift pump will effect it on the rail current i prefer to use the lift pump on and fix it then you never need to worry if you lift pump doesnt change the rail current you pump sucks or the valve is sticking

 

[TheBac]

Icant open that zip file for some reason. Thank anyway, Simon.

Here are the table values as I have then right now...

1350.000000
1250.000000
1224.000000
1200.000000
1177.000000
1166.000000
1152.000000
1136.000000
1117.000000
1095.000000
1071.000000
1045.000000
1017.000000
989.000000
853.000000
547.000000
103.000000
0.000000
0.000000

So you're saying to raise those first values to 1700 and 1650 to start, and then smooth the remaining to that? OK, I can do that.

Going to pick up our windows in a bit, so hopefully I can get to this later on tonight.

Thanks for helping this tuning-dumb person out.

 

[TrentNell]

Tom I would start around 1550 and only go higher if needed , if it still happens at 1700 then you have a regulator issue .

 

[sweetdiesel]

Tom I would start around 1550 and only go higher if needed , if it still happens at 1700 then you have a regulator issue .

X2

Tom install a stock table and then try adding 5% to the first 3 numbers
I looked that is all it toook to fix mine

looks like you run 0 in the last 2 numbers so dont forget about that

 

[TheBac]

Finally got to it. Raised first three to 1650/1590/1478 and smoothed the rest to my race tune table values. Idle is a lot better now. Still surges slightly when cold, and every once in a while when warm. Its a hell of a lot better than before, though.

Thanks Trent and Simon for the help. I really appreciate it. :hug:

Also...I noticed when I turned my fuel pump on, the surge increased in both intensity and timing before I started playing with the values. It also does affect the truck after the changes were made. Would the pump pressure being too high cause that?

 

[sweetdiesel]

Finally got to it. Raised first three to 1650/1590/1478 and smoothed the rest to my race tune table values. Idle is a lot better now. Still surges slightly when cold, and every once in a while when warm. Its a hell of a lot better than before, though.

Thanks Trent and Simon for the help. I really appreciate it. :hug:

Also...I noticed when I turned my fuel pump on, the surge increased in both intensity and timing before I started playing with the values. It also does affect the truck after the changes were made. Would the pump pressure being too high cause that?

Tom this is why i like to watch the rail pressure and current
a lift pump is essentially opening the barrel on the regulator so you need to change the current(b1010) to try and give it more resistance. kinda

glad its better for you and that you fixed it 1650 seems a little high but whatever works

 

[onebadduramax]

I'm having the same issue. But I'm getting a p00193 code. My truck is tuned by duramaxtuner.com for the LBZ FPR. I've been running this setup for 2+ years no issue till about 2 months ago. The railpressure would jump to 26k. and would not turn over. But after the truck would cool off for a few hours. IT would star up. A month ago I towed it home. As soon as I got off the tow truck it started.

So I got a new LBZ FPR on monday, drove the truck all day yesterday and the problem came back a few hours ago. I had to tow the truck home . Again once it got off the flatbed tow truck about 15mins ago, the truck started up just fine. WTF!!!!! Ideas?????? Anyone know where I can get a new harness? I'm wondering if there is a short because I hear the FPR ticking again. So I know that is fine, since it's brand new. Electrical issue maybe?

Sorry to jack the tread but I need answers please

 

[Burn Down]

Sounds like a wiring harness issue to me... You could try moving the harness around while the truck is running. Listen for the fuel knock when it looses connection.

 

[onebadduramax]

here's a video of it, i took a month ago.

http://www.youtube.com/watch?v=cxkwOSjkcCs