5.3 ls with ls6 intake, tb, injectors, etc. Need some help with a base tune

[xmbreezy]

I had an LS1 in my S10 but long story short I am now running an 5.3 with a bunch of LS1 parts and I am having some issues with it stalling once in gear. Below is my setup before i start rambling on.

2000 5.3 iron block w/ 46k miles
799 heads w/ TSP dual Valve Springs
custom ground cam 226/232 .600/.600 111 lsa +4
LS6 Intake, ported ls1 tb w/ ls1 injectors
A fresh 4l80e trans w/ a 3,400-3,600 circle d stall converter and 3.73 gears in a ford 8.8

I know you will all say I need to get it tuned I plan on it after I get some street time to make sure all the bugs are worked out. The base tune I started with was from a 2000 silverado with the 4l80e segment swap already done. I have already adjusted the tune for the ls1 injectors which i believe I did correctly. I already used the guide in the how-to section to get it to idle better with the cam https://forum.hptuners.com/showthrea...e-(w-pictures).

I found that the engine will idle without dying with the maf unplugged for obvious reasons, so right now I have the MAF out for now and the wires tucked away. One of the things i noticed in the 5.3 tune is that it's for a DBW TB, should I have used my LS1 tune instead? I already have a ls1 base tune for the ls1 cam I had so I can always jump to that instead. So the the first issue i have is when I put into into drive, i stall pretty much right away.

The other issue is I feel like i have no brakes but if i recall it's because i do not have enough vacuum for the booster to help. I also recently re-did my brake lines, installed a new master cylinder prop valve and also a line lock. I am almost positive that everything is all bled properly too.

[MITuning]

So in the tune did you disable the Maf and force speed density ? You said you took the Maf completely out right ? Did you add a IAT since the Maf has one built into it ?

[cobaltssoverbooster]

the 5.3 should have the internal iat as mentioned previously. this is a critical sensor for density calculation in SD mode. By removing the maf and not including an external sensor to allow that information to be used you cause a huge density calculation error.

you need to follow these steps to properly disable the maf sensor.
1) set the maf high rpm enable to 12,800 or anything above your maximum achievable rpm. Engine section
2) Set the maf fail hz to 0. Engine diag section
3) set p0101-103 to fail on first error and uncheck the ses box for each to keep the dash light off.

its highly recommended to have a wideband installed and functioning as it allows the ve table to be calibrated without changing tuning techniques part way. it is also the only way you can tune wot fueling.

you pe table is super rich for an NA engine. If your running any boost then you need to perform an OS upgrade. on a general level you should be targeting between 12.3-12.7 for NA applications. Some tend to run slightly leaner than that but i wouldn't go any leaner than 12.9-13 personally. i would like to take this time to emphasize the importance of having smooth tables. Right now its kind of spikey, which can cause cylinder loading issues. the smoother the commanded changes are the smoother the tuning will be.

i would spend some time disabling the traction control and drivetrain abuse. those values are calculated based on sensor input and if triggered can cause issues. catalyst heating also falls under this calculated system and can be disabled until you sort your ve out to prevent forced over fueling which can mess your ve tuning up.


the in gear and p/n raf values will not match exactly as you have them. in gear is a heavier load on the engine and will always require more air than p/n. i suggest you spend some time reading on the RussK Idle techniques or i have a file link i have posted in the forum which is a public file that restores an old but good idle how too.

[xmbreezy]

Alright I have my idle pretty much straightened out. The issue was that I did not originally tune the MAF out correctly. My only issue now is that I need to wire in a PN switch because once I put my truck in gear, it idles way too low and dies out. Does the computer need a ground to know that it's in park/neutral? I have the switch on my b&m hammer shifter and I plan on wiring that up hopefully today.

[xmbreezy]

Wired up the park/neutral switch and the engine still wants to die in gear. Any suggestions? I'm still messing with the base idle airflow table and it's not really making a difference in gear.

[lukearmstrong1990]

in gear idle require more airflow to maintain RPM because its under greater load.

does your scanner show you when its in P/N or gear and does it switch spark and idle tables

[xmbreezy]

After thinking about what cobaltssoverbooster and researching further, I need to adjust the ve table.

[DrLoch]

If you still need an IAT sensor look here, http://www.lsxtune.com/shop/product_...roducts_id/400 Used them a number of times

[xmbreezy]

So my issue appears to be related to not having the PN switch and gaving by selecting the table in hptuners to say NO PN or PRNDL switch. The truck moved and didnt stall immediately in gear or reverse. I'll have to go through and re do the russ k technique to get it to idle better. Thank you for everyone's help.

[xmbreezy]

So i've been playing with my tune some and it dies great after doing to russ k idle setup. I've done a couple test drives and i'm having an issue where it still wants to stall at a stop sign yet it idled perfectly when I did the russ k. If someone can take a look at my tune and long, that would be great.

[TCSS07]

your base running airflow numbers are pretty low and backwards you have p/n requesting more air than in gear in the operating temp range
switch those around and change the units to g/s and add 4 grams to the whole chart then switch it back to lb/h and re test

idle desired airflow is wanting 9 g/s and your only giving it 3.5 g/s

[xmbreezy]

Alright so I did that and now it's better but still drops the idle real low at stop sign after coming to a complete stop. The idle never recovers and step on the gas has no affect at all

I'll probably have to re-do the base airflow again because the idle doesn't drop to my command rpm of 950 for both park and drive. Here's the log i took as an fyi, I had to shut the truck of and turn it on again to get the rpms high enough to be able to throttle it to move.

[TCSS07]

still think you need more air for the in gear at those temps - try adding a couple more grams in the base airflow - my buddies ls1 big cam heads 102 fast tb and intake i have at 100 lb/h at 176 on up - his is stick but just letting you know its not uncommon to have large base idle airflow numbers and being automatic you may need higher because of the extra load from the trans/converter
disable stall savor under idle rpm - 0 out p/n and in gear
you can also mess with throttle follower tables
throttle cracker causes the hanging idle during coast down if you encounter that

heres my buddies base idle numbers
229.17052154118 207.515271365786 185.852270563987 164.197020388593 142.541770213198 120.878769411399 99.2235192360048 99.2235192360048 99.2235192360048 99.2235192360048

[xmbreezy]

So I disable the stall saver, boosted the base idle numbers. That still didn't help and i'm still dying at the stop sign. I did some more research and I saw that raising the 4 timing tables should help. So I added 3 degrees of timing from 0-800 and then tried it out. When I stopped at my favorite stop sign it didn't stall but as soon as I hit the gas and started to roll, the truck fell on its face.

Here's the log and last tune.

[lukearmstrong1990]

I hope that wideband in the log isn't correct.

disable the LTFT. if you're not using STFT then don't let LTFT make corrections.

your idle spark overspeed and under speed correction tables should be somewhat close-ish to each other with the exception of one being negative values and one being positive values.

you need to look at reference at what point the spark tables transition from idle to main. the log shows .40 and under areas under 1000rpm still referencing idle tables which asks for very little timing for idle with a decent cam.


throttle cracker enables at 3km/h. you seem to be having issues between 3 and 10km/h in the 1000rpm area as you're trying to transition. 6.4km/h and 1000rpm cell in throttle cracker is 0.00. its not trying to add any air at all.

the whole calibration need more air at idle/coast down.

your VE table looks like it would better suit a stock cam engine. if you're too rich or lean at idle or low RPM then you're fighting a loosing battle with the rest of it.

you have a 3500rpm high stall. you're on easy street. give it more air to the point it idles high and rev hangs then reduce it. it will save you trying to data log on a car that stalls all the time.

[xmbreezy]

Thank you, yes you are correct. The wideband isn't logging properly. I'll take a look at it tonight.

[xmbreezy]

I wish I could say my truck was running fine but unfortunately it isn't. Since I started this thread, I ended up throwing on a truck intake and injectors. I also took the truck reputable shop to tune it but when they did the pre-dyno checklist, they found too many things wrong with the truck and Icouldn't afford to have them fix everything. Vacuum leaks were one of my major issues but I can confirm they're all gone with a home made smoker.

The newest issue while doing the russ K idle method in gear, the rpms drop to 400 and it eventually dies. I've tried messing with the timing and also the RAF tables but I can only get the truck to move with the help of throttle. Can someone tell me if i'm missing something major in my tune, I have it attached.

I have been following the below link as a guide.

https://forum.hptuners.com/showthrea...e-(w-pictures)

[cobaltssoverbooster]

i dont think your scanner is set up correctly so lets go through a quick little test of a few things.
first i would pull your gauge and move the switch in the back to position 1. this should make your wideband display in lambda. i do this to test the ecu's stoich value. to do this leave your trims active and turn it on and see what the gauge display reads at idle when the trims kick in. it should be very close to 1 once it settles in. if not and it reads higher than 1.0 then you need to lower the stoich value until this test stays close to 1.0 on average.
you can now switch the gauge back to position 0 to read afr again.

go in the scanner and see if the afr gauge is reporting the same in the scanner as the gauge does. if it doesnt then you need to transform the wideband channel. Right now i believe this is not accurate because your trims are actively targeting 14.68 and your sensor reports back in the 10s. im guessing your gauge face says its closer to 14.7
once transformed correctly shut the fuel trims off and rely solely on afr error. this will tune you faster and more accurately than the trim system will. Fueling is critical for a controllable idle so setting this up properly is going to remove a lot of headaches.

i would start the braf process by disabling active idle trims and monitoring idle desired airflow against coolant temperature. just do it for p/n and let it sit from cold start to full temp collecting log data. copy the values from the log and paste them into the p/n braf section. now paste them into the gear section and add 2-2.5 to the values you just put in the gear section. it should idle on its own now accurately enough to do the same recording process while in gear. adjust your fueling errors for park and idle then verify your braf values one more time.
at this point you can resume the idle tuning methods and reactive idle trims to allow stit and ltit adjustment.