idle pulse width ???

[truckie]

Hello all, I'm in need of some help. Is a 3.8-4.2ms injector pulse width normal at idle and correct?
I have a 2000 4.8/4l60 po1 that ran great, I then put a 228/230 585 112 cam in it with PAC 1218's, racetronix/lucas 42lb injectors, long tube headers. I can not get this thing to run right, idle pulse width's seem high to me from what I have read. Still has factory converter, 3200 enroute. I can get it to idle decent in park at 800 rpm's wide band 13.5-14.2 but when I put it in gear it idles way down, wide band goes lean, injector pulse width's go up and it runs like shit or stall's. I have played with the injector flow from 36-55, I have added up to 50% to the offset in both directions, can not get the pulse width's to go down. What am I doing wrong? here are a couple tunes and logs.

[5FDP]

Are those injectors rated at 42.5 psi or 58 psi?

Your truck runs 58psi so you need to set the flow rate for that.

Once set, stop adjusting it. The rest of your adjustments for are going to be with your VE tables and MAF tables. Those control fueling.

Also on a quick look, go back to stock like timing tables. Only going to 28 degrees advanced during normal cruising rpm is just going to hurt you. Less MPG and to me worse for tuning. These engines love going into the mid 30's to low 40's for timing at cruising speeds.

[SultanHassanMasTuning]

low 3's for IPW is what i would aim for...

[truckie]

They are rated at 40.1 at 3 bar so I believe that makes them like 46.29 at 58 psi. If the ve changes up and down do not correct the problem where would you look next? I will switch the timing tables, thanks. Out of curiosity why do the factory tables have negative values? So low 3?s for idle pulse width is normal? I have also been told to change the values in transient, thoughts? Im really trying to learn this stuff, thanks for the help. Planning on taking a class in January at the tunining school.

[truckie]

Ok playing with it turned closed loop back on, wide band reads lean and graph tells me to pull fuel. So I noticed when I put it in drive bank 1 stays around 300mv and flat bank 2 goes up to 8-900 and looks like a mountain range? Is this faulty injectors or computer issue?

[5FDP]

If the wideband read lean the fuel trims should be showing positive as the computer has having to add fuel, not remove fuel.

Leave it in open loop for now and tune your airflow model. Then turn the trims back on once you get it running good.

If the fuel is this far off the o2 sensors are not something you can really trust at all, they are going to be all over the place. Use the wideband instead to dial everything in, then go back to using fuel trims for final fine tuning.

[truckie]

Thanks for the help, I turned all narrow bands off and moved my wide band from bank1 to bank 2 and they were 2+ points different. So I believe its time for new injectors! Unless im missing something?

[5FDP]

Did you trouble shoot anything else before hand?

A vacuum leak or a header exhaust leak is something you should look into as well. Swap injectors side to side too before buying anything else.

[truckie]

I checked no exhaust or vacuum leaks. I will try swapping injectors around. Im also going to add a second wide band have one in my other vehicle so I can read each bank simultaneously
I swear everyone makes this look so easy and its kicking my ass!

[truckie]

Ok, I believe I might have found the problem. I don't quite understand it? I put a wide band in each header, the banks are very close to each other. I can get a nice smooth idle 14.7 afr at around 800 rpm's at 60-65 kpa with a 1 bar speed density tune. If I adjust the cells in the 60-65kpa area I can move the afr up and down. When I put it in gear both wide bands go lean and the truck fights to keep the rpm's and starts to surge. I can add as much fuel to the in gear kpa as I want, no change still goes lean. In gear kpa 75-90 it moves around. I have done a tps and iac relearn, I do not know how to change the steps for the iac. I unplugged the iac in park and there was no change, unplugged the truck dies immediately in gear. I can put it in gear and foot brake it to .5-1% tps and it will idle at 13.8-14.2 steady and smooth around 750-800rpm, let off the pedal wide bands go lean and motor starts to surge. If I open the throttle anymore the in park idle goes to high. Do I have a bad iac? Can I open it more when it goes in gear and how? I see the iac steps vs effective area but I don't understand the numbers?

[Alexistec18]

Truckie! Did you figure out you lean in gear condition? I have a similar consider, Idle great, Part and WOT are good but Idle in gear goes extremely lean.