5.3 with LS9 cam and LS6 springs will not idle correctly (rich) PLEASE HELP!!!!!

Hi, this is my first time posting on any forum but i really need some help.

This is my first build really to dive in to the automotive world, learn how to build motors and add stupid amounts of power.
Build was going great, small trips along the way but everything was fine ..... up until the tune came along.

i have a 5.3L Gen 3 Truck iron block with LS9 cam and LS6 springs
LS1 intake
ebay 42# injectors but i feel like they weren't helping on the tune department so i reverted back to stock truck injectors.
External fuel pump.

At first the car would run fine, AEM gauge read 11 sometimes 10 i know thats really rich but the car sounded somewhat healthy so as my attempts started go towards a mid 13 or low 14 the car did not what to stay running. would often dip to the 20s or not read anything. would surge like crazy on start ups and then dip to the 10s.
The motor surging is really what kills me.
Ill admit i don't know what i'm looking at but dammit I work on this car pretty much everyday and i really want to learn.
So if i can get some help I would be eternally grateful!!

I Will try to attach the file i keep on messing with along side some of my Logs if that helps!


I should also add the spark plugs are BLACK!!! they were brand new but it ran way too rich, not sure if that would cause it to not run properly.


Please and Thank you
Attachment 86730Attachment 86731Attachment 86732

In log "test 13.hpl" your B2S1 02 sensor isn't reading correctly or you have a massive exhaust leak.

yeah i don't have the exhaust fully built yet only passenger side where i have the wideband and the regular o2 sensor bungs installed ,should be o2b1 reading differently tho, would that affect the tune in any way???

Get your AEM into a log using the analog input on MPVI or go through EGR circuit, plenty of info around to help with that. You made the investment into the AEM, use it to its max potential.

Use the attached channels list to log with and use the layouts with each channels list. The fueling channels is setup for AEM analog in and should be good to go once you get the wiring done.

Did you put the stock avalanche injectors back in?
Did you save the stock tune file?

Once you get the injector data correct you can get this dialed. This setup will be easy to calibrate once you get the correct data in places.
Remember bad data in is bad data out.

I'd plot your bank 1 and bank 2 injector pulse width so we can see what the fuel delivery is. I would plot misfires on each cylinder if you can so we can see if it misses. Test 11 never goes to closed loop. Bank 2 is lean in 13 and adding fuel. Where are the o2's located (distance from engine), do the 02 sensors have power to the heaters (excessive time to closed loop) and could you have vacuum leak on bank 2? Where is your wideband sensor located? On bank 1 or 2? Assuming dual exhaust? The more channels you post, the more info we have to look at. On the exhaust, I see our posts crossed paths and did not see your new post.

hmm i wasnt aware i could use the aem on the ecm, i do not have an egr valve the donor truck did not have the egr circuit on the truck intake.
I did reinstall the stock truck injectors again, im not sure if i have the unmolested version let me see if i still have it on my Documents.
however ive been trying to keep tune on open loop but from what DGS says it means its going closed somehow??.
How do i know that i have a vaccum leak on bank 2 ive plugged every hole i see exept the brake booster one which has a plug and a breather line that now has a filter attached.
I will definetly place those values on the next test here pretty soon hopefully that will give more insight on my situation.

looks like i do have a somewhat untouched file i think, i think i just messed with the idle and the main ve oh and a little bit of the Open loop eq ratio i think before i decided that i needed a fall back :(
Im dumb i know :( :(
Attachment 86740

ECM wont be able to use the AEM. If you have the MPVIpro you can use the inputs on the side to get the analog signal the AEM produces, with some wiring, into the HP Scanner. If you don't have a MPVIpro or the expansion cable for the MPVI2 it will become more of a challenge to get the actual AFR from the AEM into a log to make the proper % of error change to the MAF curve and VE table. You need to correct the airflow models, MAF curve and VE table, if you ever expect to get the vehicle to run let alone behave.

This part I would recommend getting addressed after you get the proper data into the tune for the injectors.

daing the pro upgrade is another 250 ish ?? oof thats gonna put dent in my progress

Wire the wideband into a 5v circuit on the computer. I used the EGR circuit because it's easier to setup on vehicles that aren't using that sensor. Lots of video's and write ups on doing that. And it's free to do, or less than 10 bucks if you don't have PCM wiring pins on hand.

Also if you are running stock injectors again, put the stock data back in the tune file.

Disable closed loop and all fuel trims if the exhaust is not finished. Make sure fuel pressure is steady at 58psi.

You must disable all rear o2 sensor codes if you are not using them, also the cat over temp must be disabled.

oh i actually didn't know about this i sure will do this first thing tomorrow, however on the hpt i do not know how to disable closed loop , i do know how to disable sensors or at least the ecm to stop reading them.
this is all great haha.
i know all yall more experienced folks are looking down on me calling me a rookie :(

Closed loop disable;
Go to Fuel > Oxygen Sensors:
closed loop enable table set to 285 *F
Long Term Fuel Trims Min. ECT set to 285*F

Go to Fuel >Open Loop/Base:
toggle STFT Open Loop set to Disabled

If I owned a MPVI2 I'd do the changes for you to show, as with many other people because this is just simple stuff but I don't have one. Still rocking the MPVI for a while yet.

Quote:

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Originally Posted by Angeldelgado

yeah i don't have the exhaust fully built yet only passenger side where i have the wideband and the regular o2 sensor bungs installed ,should be o2b1 reading differently tho, would that affect the tune in any way???

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There's your problem. Get the exhaust system built. As any exhaust leak close to an O2 sensor will cause positive fuel trims & fouled spark plugs.

Russ Kemp

Russ, 5FDP and Cobalt are wise in wisdom and out of anyone on here those 3 know their stuff and have great suggestions and information.
Finish exhaust, get WBO2 working in the scanner by what ever means necessary, fix the tune with the correct injector data.

Is the stock tune you posted above from the vehicle the engine and injectors came from, for sure?

I made some changes based on the 2 files you posted, the file I sent you is MAF only and LTFT off as this may help you get rolling and fueling dialed quicker. Some people do the MAF first and some do VE first, basically comes down what came first the chicken or the egg. If the injectors are not from this ECM/Engine combo we need to know what they came from. Sorry to sound like a broken record but the 1st step is correct injector characterization data as most if not all calcs are based of the injector characterization data.

Okay sorry for the no replys. Life is getting in the way.
Anyway i Used the Base tune DHC provided. Inputed the values of Misfires on Cyl 1-8. Injector pulses on Banks 1&2.
I have not gotten to inputing the wideband through the EGR circuit because the 03 ecu doesnt have a pin decignated for the EGR but im hoping if i use 01 pin layout i can use the pin 7 on red to tap into it.... atleast thats what i hope to do.
Fuel injectors are from a 01 Tahoe sorry i should have mentioned that earlier, i made the mistake of assuming that all truck injectors are the same.( Ill try not to do that again :( )
The Exhaust is not complete yet either but i will try and finish it this weekend hopefully.
Wide band is on Passenger side with stock o2 with a exhaust pipe
Driverside is not complete.
Found a Vacuum leak from a line going to the TH 350 ( i will place a thicker line in the near future, but for now i hope that i was able to patch it up)
replaced the intake manifold gaskets.
Correctly installed fuel rails with spacers for the truck injectors ( no leaks so far!!! )
I live in Houston TX if that makes a difference



So with that Being said The Log provided has an intereting start up idles arround mid 12 which is still rich but its better than before. However it seems as if its iddling at 1k rpms

hmmmmmmmmm.......

Attachment 86829
Attachment 86830

Also Thank You All for the Help and tips , You don't know how grateful i am !!!

Assuming, we know what happens there, are from a 01 Tahoe 5.3 A4 the injector data is slightly different, different enough that will need to be changed. You really need to get exhaust done and sealed before you go any further, unless you like chasing your tail. Maybe try and get exhaust done along with getting your WBO2 sensor reading in the scanner.

With that said I would like to see start and idle log using the LS1b fueling channels being used. Without a log it is hard to see if there is too much BRAF, timing, fueling, ect.

Quote:

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Originally Posted by DHC

With that said I would like to see start and idle log using the LS1b fueling channels being used. Without a log it is hard to see if there is too much BRAF, timing, fueling, ect.

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I will definetely do that. I can rig something up for the mean time..
But this Ls1b Fueling channels??

hmmmm google search here i come!:pray:


Do you mean A chennel to tell if its on CL, OL, or OL fault??