LQ4 twin turbo not responding to VE changes, speed density setup help?

[BOAT8KR]

Hey guys, I searched and could not find a post similar to my situation. I have read these forums for a long time, but just registered recently.

I have a P01 ecu controlling a stock lq4 with twin turbos (about 8psi) on 91 octane and a 4l60. FIC bosch 72lb injectors, calibration data provided by fuel injector connection, I setup RTT 2 bar OS per instructions from HPT, with real time tuning on using VE/SPARK/PE. No MAF on the car whatsoever. the car starts well, drives decent for a base tune. Far from perfect. However, the car is not responding to real time tuning changes on the VE table and also does not respond to flashing the car with VE changes eiher. I will attach the map I have in the car, keep in mind this is far from being done, I feel like I am missing something, not sure why it doesnt respond. Can someone verify my MAF settings are correct for what I am doing, and that I have setup speed density properly? The car Idles at 11.0, vcm scanner says commanded afr is 14.68. I have used all the calibration data for the injectors that was supplied to me. Using real time tuning in the scanner, I can drop ve at 25kpa (idle) clear down to 20 and it doesnt respond. however, if I go lower than 15 or so, the car starts to sputter and leans out to 14-15 afr. I bring it back up to 18-20, and afr drops back to 11.0. I hope I have just missed something simple. Can anyone verify my injector calibration data is correct? FIC 72lb bosch injectors. I will also supply my injector data sheet from FIC as well. On startup idle is about 12.2, then slowly richens up to 11.0-11.5 and stays there. all logging was done at 190*F.


Thanks for the help

P.S. (what is the correct part number for the 2 bar map sensor, anyone?)

[blindsquirrel]

File is tuner locked.

[BOAT8KR]

File is tuner locked.

Sorry! I have unlocked it now, and loaded the file. Thank you Blindsquirrel.

[BOAT8KR]

BASE MAP 2 BAR UNLOCKED, remote tuning off.hpt

Unlocked File^^

[5FDP]

It still says it's part of a remote tuning network.

[BOAT8KR]

alright guys. I am sorry. I believe I cleared the remote tuning network key/code. if there is something else I need to do to unlock this, let me know. I apologize, and thank you for the help.

the new tune has been replaced above, should be good.

[5FDP]

Okay, this one works.

So now for a question.

What MAP sensor is installed at the moment? The tune says it's a stock 1 bar GM sensor but are you running a 2 bar sensor or 3 bar sensor??


Under the transient tab, change the min fuel milligrams from .041 down to like .010, this should help with a rich idle most of the time on big injectors.

Careful with the boost enrichment, you have it disabled with the 1,280kpa enable. So if you get into boost it will only command what the PE is set too. Maybe change that to 105-110kpa instead.

Try to find a 2001-2002 half ton open loop eq ratio fueling table. It won't be as rich at cold temps and it should level out to 1.00 (stoich) above 140 degree coolant temp. Those give a better base to work with instead of the LS1's open loop EQ ratio tables.

[BOAT8KR]

Awesome. I missed the BE kpa, I have them now set to 110 enable and 105 disable.

Thank you 5FDP, I will report back if I have any issues. I have over a foot of snow here, and its still snowing... ugh. I hope to try this out today.

[BOAT8KR]

It shows 2 bar OS on my end in the calibration notes.... hmm. I will check what MAP sensor is in it.

[5FDP]

Yes, the calibration is a 2 bar OS but that's not what I mean. The MAP sensor data is that of a 1 bar MAP sensor. The settings are 94/10 where as a 2 bar sensor is likely 200/8 or 200/10.


The way you typed out the changed MAP settings makes me want to tell you to read the boost enrichment/power enrichment things a little closer. The MAP hyst is not a disable setting like you may think it is. It's not going to turn on at 110 and turn off at 105kpa like you just typed out.

Hold the mouse over the PE hyst and read the blurb at the bottom. The hyst settings is subtracted from the map enable setting. So your trigger is 80 and it will disable at 74kpa based on the current setting, that is totally fine.

If 110kpa is what you wanted, you need 5kpa in the hyst setting for boost enrichment, then it will shut off at 105kpa.

[BOAT8KR]

Yes, the calibration is a 2 bar OS but that's not what I mean. The MAP sensor data is that of a 1 bar MAP sensor. The settings are 94/10 where as a 2 bar sensor is likely 200/8 or 200/10.


The way you typed out the changed MAP settings makes me want to tell you to read the boost enrichment/power enrichment things a little closer. The MAP hyst is not a disable setting like you may think it is. It's not going to turn on at 110 and turn off at 105kpa like you just typed out.

Hold the mouse over the PE hyst and read the blurb at the bottom. The hyst settings is subtracted from the map enable setting. So your trigger is 80 and it will disable at 74kpa based on the current setting, that is totally fine.

If 110kpa is what you wanted, you need 5kpa in the hyst setting for boost enrichment, then it will shut off at 105kpa.

That makes perfect sense. I need to just slow down and pay attention. I am used to tuning older Ford Modular with MAF, so this is the first time I have tuned with VE and BE. Thank you for the help.

[BOAT8KR]

update:

I checked my map sensor, never trust the customers word lol. stock 1 bar sensor. ordered the 3 bar ls1 truck style clip in map sensor from the efi source. corrected map sensor data. I will install it and load the new tune and let you know how it goes.

[adnoh400]

update:

I checked my map sensor, never trust the customers word lol. stock 1 bar sensor. ordered the 3 bar ls1 truck style clip in map sensor from the efi source. corrected map sensor data. I will install it and load the new tune and let you know how it goes.

Not to be a wet blanket, but I just had to replace that sensor because it does not read accurately. Apparently the only ticket is the GM 3 bar from the ZL1

[BOAT8KR]

Not to be a wet blanket, but I just had to replace that sensor because it does not read accurately. Apparently the only ticket is the GM 3 bar from the ZL1

what readings were you seeing?

[BOAT8KR]

Not to be a wet blanket, but I just had to replace that sensor because it does not read accurately. Apparently the only ticket is the GM 3 bar from the ZL1

is that a clip in style? ive found many ac delco options but none for the clip in style truck intake.

[adnoh400]

is that a clip in style? ive found many ac delco options but none for the clip in style truck intake.

Yes the clip on style. I have given up finding one that actually works. Going to pipe the good sensor in.

[adnoh400]

Was getting about 105kpa with key off. low reading under boost, high reading under vacuum.