I tuned a 06 LBZ and keep getting a P0089 code. My pulse width is at 2800 for the high end and I thought I had all the P0089's tuned out of it. Well the other day..... he met up with 2 other guys with trucks that I had also tuned....... and they had been in the suds.... well the P0089 reared it's head again. Before all of the codes were being set at 75mph+ originally and I had it tuned down to the point were it would through the code at 120+ mph....well the other day it popped at 45 mph out of the blue on a hard roll in from 35.


Needless, to say I am one mad hombre. I gave him a PPE race valve... I hope this cures it, but I have my doubts. What else will cause a P0089?

Is 2800 too big for pulse width, I am puzzled because the LB7's I've tuned are fine at 2800. I checked under the hood for the smell of fuel and found nothing.

Any help?:D

do you have a lift pump and new fuel filter?

No lift pump..although it will come.... He said something about changing the fuel filter maybe we'll try that first. We thought of it, but then forgot.

He just bought it used, so a fuel filter may be needed.

Thanks.... any other ideas?

A lift pump needed. I can still throw the P0089 when sled pulling if they have the sled set up very heavy. It really sucks when pulling because the motor defuels just like letting off the gas. I wish I knew how to write it out with efi but I cant seem to do it. The lbz is BAD about it. I THINK if the actual FRP drops more than 1500 US from the desired for so many cycles it pops the code. If someone can help please do.

lift pump and shimm the fuel release valve
thats all i have and i can run up to a 3400 shot with no 0089

lift pump and shimm the fuel release valve
thats all i have and i can run up to a 3400 shot with no 0089

But can you do this while sled pulling? I can run that much duration on the street also, but when hooked to a very heavy sled it pops it every time. When they ramp the weight up slower it has no problems. I also have never thrown the code in the 7500 lb class. Its just the 8500 class with weight ramping very quick.

Are you guys sure you're talking about the same code? Here's what I get for P0089 when I look it up in the DTC tool:

Code: P0089
Modules: ECM
Description: Fuel Pressure Regulator Performance

I haven't heard of too many people having issues with this code, but I have heard of problems with P0087:

Code: P0087
Modules: ECM
Description: Fuel Rail Pressure (FRP) Too Low

MY BAD its the P0087 I have troubles with.

I had the same problem with the 0087. lift pump fixed that problem.

P0089 dosnt show up for a 2006 LBZ in the service manual anywhere.

Sure that its a p0089?

Cobra...


MY BAD its the P0087 I have troubles with.


;)

LBZ_GMC,

I tuned a 06 LBZ and keep getting a P0089 code.

MY BAD its the P0087 I have troubles with.


2 different people, my post was ment for the orginal poster. :)

Okay a Poo87. I would have to go log it again. Shint. lol