po200 code on 55 belair

[badbowtie]

Please scroll down to my next post and you can see what I did.

I have a 55 belair that has a 05 4.8L in it with simens 60lb injectors and running e85 I drove it the other day and noticed it was going lean on cruise. My wideband was showing like 1.27 so I was looking at laptop and noticed that my short terms were not on. So I commanded closed loop and they turned back on and bank one was about normal again like + or - 2 percent and bank 2 was about 20-30 so I knew bank 2 was problem. So I brought it back home and replaced battery since the optima was 9 years old and I had to jump it to even start it that day. So new battery is in and still having the p0200 code. I went thru and commanded each injector off one at a time and 2 did not change anything so I figured that was the problem. So I grabbed stethascope and sure enough I can hear it clicking no problem. I even took a noid light for gm tbi unit and put wires on both ends and touched the wires in the end of the plug and sure enough it flashes. I then let car get all the way to normal temperature and then noticed that clicking number 2 of again does change it. So does it mean I have a flake injector or ecm is bad. I thought about switching to 80lb soon but not sure if that is the problem or do I have a bigger problem.

[AutoWiz]

It is easy to test for injector failure. Simply swap it with another cylinder. If the problem moves then replace your bad injector. If not then this might be a wiring issue either between the injector and ecm, possibly even an expanded pin for that wire in the ecm connector making a poor connection, Or there might be a breakdown at the splice where ignition power breaks out to that injector. You should save damning the ecm for last failure is rare enough that it is ok to explore all other possibilities first. A lab scope would be your best friend here. But a dvom is a required minimum for tracking this problem down.

[badbowtie]

So I went ahead and replaced all my spark plugs with ngk b7ref plugs and I went ahead and ordered a set of siemens 80lb injectors before I put the injectors in I started it and let it idle and never had the injector code. But I went ahead last night and pulled the fuel rails and went ahead and replaced the injectors. I installed this tune that I thought I switched everything over for the 80lb injectors but you can see it is idling really rich still. Please take a look and see if I missed something.

[5FDP]

If it's still a little rich, just remove the some fuel via the VE table.

[badbowtie]

I also may of figured it out I am running a vacuum fpr on rail so I need all the numbers across the flow rate vs kpa table the same.

[AutoWiz]

I also may of figured it out I am running a vacuum fpr on rail so I need all the numbers across the flow rate vs kpa table the same.

Idk why you would run a vacuum fpr. Usually the gm filter/regulator is the preferred way to supply 58 psi to our gen 3 LS engines. But no matter what regulator setup you have injectors flow more or less when there is or isn't a negative pressure applied to the pintle. And furthermore the injector will also flow more or less if a negative pressure is applied to the fpr at idle or just certain points of the kpa spectrum. This is why we have that table. Do you need a hand setting it up?

It is a simple thing to setup flowrate vs. kpa. All you do is before you make any changes you figure out how much the difference is from one end of the table to the next. It should be a pretty low number, but it is an important number. And this number BTW has nothing to do with a vacuum line attached to an fpr. So I don't know how you would correctly compensate for that. But then you would take your new injector flow rate and put it at 0 kpa. Then you would add your new flowrate to the difference between 0 and 80 kpa on your original tune file and put that number at 80kpa. And then interpolate between 0 and 80 kpa.

[badbowtie]

I am running a truck intake with truck rails still that has return on the rails. So that is the way I have had it setup I also think I have the flow rate correct know I have it set at 94.6 accross the whole table. When I was running the 60s I was using 72.6

[badbowtie]

Okay I switched the flow rate vs kpa but sure still dont seem right. I have tried to look around I am kind of thinking I have something messed up in the injector stuff because It was not subtracting all this fuel when I just pulled the 60's out. All I switched was to the 80's and now I am this rich.
Here is current tune and a log while idling. If someone could take a look and make sure I switched everything correctly for the 80lb injectors that would be great.

[AutoWiz]

So I really hope this long holiday weekend has learned us all here on the gm gen 3 v8 section of HPTuners forum the importance of smooth tables with as equal and gradual changes from one cell to the next as possible. This thread is no different. Here is this person's ve table:



Despite the log only showing idle, one look at this table in 3d view should confirm to just about anybody that this controller is not capable of fueling correctly. One more time, this table needs to look closer to this:



With the high spot being right before peak output. Get the basic shape right, get it smooth, and tune it to what your o2 sensors are telling you and smooth it some more. I still say that to just put the same value at 0kpa as at 80kpa of your flowrate vs. kpa table is to completely undo the whole point and idea of having that 2d table instead of just a loose guestamation that these injectors will flow this much. They will certainly flow less when vacuum is applied to the regulator and the effective spring pressure becomes less. And the injectors will most certainly flow more when there is higher levels of vacuum present at the nozzle.

I also noticed your cooling fan turn on speed is set to 0. This is an obvious error as whenever you put your vehicle in drive this might shut off your fans. if the disable speed is set to 75mph(quite high but w/e) then the turn on speed should be set to like 60. So the fan will turn off at or above 75 and not turn back on until it drops to 60. But the way you have it the fans are off above 0 mph.

[badbowtie]

I smoothed it the best it would I also wish I did this everyday and had someone local to work with me. I am thinking about having the car dyno tuned hopefully soon but right know just want to get it driving again until that happens. I also was not aware of the fans being like that I thought any speed would make them come on with 0 in there. I also know as long as I am running down the highway at 70 it will stay cooler than it does if I run 77 which is why I had it set at 75. So setting it to 60 does that mean the fan will not turn on until I reach 60 mph.

[AutoWiz]

The fan on speed is below this rpm the fan will turn back on after he shut off speed has beed reached. so if you are set to disable fans at say 45mph, then you should set the turn on speed to like 30mph so you don't find yourself in a spot where the fan keeps cycling on and off. Also you need to do like this table says..

[badbowtie]

Okay so I just came in from flashing the smoothed out ve table and fan change and started the car and opened the scanner and of course it has changed again and know I am not showing my wideband info. If you look at first log then second you will see it is gone I tried to reload my layout and that didnt help.