I put a post up on the HP Tuners forums with a log and my tune.....I just hooked up my LM-1, just wanted to have some of the masters check it out, make sure I have it all set up right in my histograms and such. Also, why is my commanded AFR so low?? Is there a place where I can adjust that??? It's around 12.5:1 most of the time, is this normal for a stage2 tune?

http://www.hptuners.com/forum/showthread.php?t=14700

 

well i looked over your tune and obviously quite a few things arent right at all. i'm betting you have a check engine light on.

the obvious problem that i can see at a glance, lies in that you removed your rear o2 sensor and you havent changed the DTC settings to ignore it. and your maf sensor is failed out. these things are forcing your car into open loop. it is ignoring your sensors and forcing a "safe" commanded air fuel at idle of 12.5 instead of trying to command 14.7.

put that stock sensor back in and get another bung for the wideband before the cat, not after like the stock location. (not applicable if you have no cat converter) OR just go in and disable the DTC's for the HO2S bank 1 sensor 2. actually, heres a good link to doc's faq that will cover this. https://www.cobaltss.net/forums/tuning-131/frequently-asked-hptuner-questions-65823/
set your maf fail to 12000hz. that should get you back into normal closed loop mode.

 

well, I was under the impression to tune with a wideband, the vehicle was supposto be in open loop to tune the VE table. I do have a check engine light on for the MAF sensor that I failed. However, I did not disable the second o2 sensor, it is still in there and hooked up. Since the vehicle is in open loop it should run mainly off of the VE table since the MAF is failed...so the factory o2 sensors wouldn't be contributing to the fuel anyways???

 

yes, you do need to fail the maf to tune the VE, didnt know you were trying to do that.
in open loop the o2 sensors do not contribute to the afr, it runs a pre determined afr. thats the 12.5 you are seeing. so no it isnt "normal" for stage 2 to do that, but considering you intentionally forced open loop then it is expected. i cant see exactly what is going on in your logs since im not using the same config so i dont know if youre doin it wrong.

best i can say is if you havent already done so, i suggest reading the FAQ https://www.cobaltss.net/forums/tuning-131/ve-tuning-how-71393/

 

here are a few things for you...
http://www.hptuners.com/forum/showthread.php?t=11018
http://www.thetuningdoctor.com/HPTun...uningGuide.doc
there are more, I am just having issues finding them right now.

plus that one....thanks Bika

 

glad to help.

 

found this, specifically for the LM-1

 

thanks for the help fellas, +rep to the both of you.........

now, I have the wideband o2 set up like in the post you put up Doc........and I have had my car set up for open loop with the maf failed, the COT and DFCO disabled like in the other thread you linked Bika. My question is though, I'm still seeing a commanded AFR of about 12.5:1 and an actual AFR (per wideband) anywhere between 10-13:1. Is there anywhere in HPT for me to adjust the commanded AFR for 14.7:1????

oh, forgot to mention....I do have the factory o2 sensor removed for the duration of the tuning and my LM-1 installed in that location, I don't think that would have any affect on the commanded AFR since the car is in open loop the entire time




here's a link to a post on HPT forums with a new scan if that will help. thanks
http://www.hptuners.com/forum/showthread.php?t=14719

 

your going to get 12.5 as long as you are in open loop. do like i suggested and enable your maf, and delete the rear o2 sensor DTC and if you STILL are commanding 12.5 in closed loop, then you have a problem. it should command 14.7 at low rpms in closed loop.

as for adjusting the commanded afr, that is in your PE EQ ratio table. 14.7 (stoich) divided by your desired full throttle AFR equals what is in the cells of the PE. for example, IF you wanted to enter a commanded afr of 11.4 in a PE cell, you would do the following calculation. 14.7 / 11.4 = 1.28947. you would enter 1.28947 in the cell and that will command your afr. however, this is only for Power Enrichment. NOT your idle and cruising afr, which will be 14.7. the thread i linked to has a better explanation.

 

hmmm im pretty sure when i dropped into open loop for ve tuning i still had normal commanded AFRs.

lemme go dig through my logs, see if i can help any.

 

thanks for the help I found that to be in open loop and be commanding a 14.7:1 afr that all the multipliers for the open loop need to be set to 1 across the board. That post you linked me to earlier only had the last half of the tables set to 1 which is where I think my problem is.

 

i guess i learned someting new about VE tuning

 

it wouldn't be a good day if we all didn't learn someting new


:edit:
hmmm, well that didn't work out....I changed those multipliers and I'm still commanding a 12.5:1 afr in VE and from 11.6:1-mid 10's......someone help me!!!!lol this is driving me crazy. There is a copy of my last scan and tune at the bottom of the first page if someone can take a peek at it and help me out.

http://www.hptuners.com/forum/showth...119#post105119


:edit again:

ok, so I tried a couple different things to see what would happen....1st I tried leaving it in closed loop (closedloopve attached below). I failed the MAF, disabled COT and DFCO, I disabled the LTFT so I could try and just scan the STFT's......however, it still was commanding a 12.5:1 afr. So next I just put the gmstage2 (boostandtrque attached below) tune on and checked it and now it's commanding a 14.7:1 afr. I don't understand why it would do that......I set the MAF fail frequency to 0 and have the p0103 set up to go on first fault...this is driving me nuts! If it makes any difference I'm working off of a gm stage 1 tune....if there's any difference between that and a stock cobalt that I need to do.

there are the tunes uploaded on the HPT forums in the link I have in my post above

 

This might be a stab in the dark, but any chance you're going into limp mode in VE? The scan kinda looks that way. Set up your tune, just like you would for OLSD, except don't fail the MAF. If that works, go ahead and tune your MAF. Then go to engine diagnostics and set P0068 from 800 to 8192 (max). See if that helps.

The only thing it doesn't explain is how you can even go WOT. Like I said, stab in the dark. Also, I have never seen an O2 that steady. Sure it isn't screwed up?

 

well, I am able to go WOT....I had a couple pulls whereI went to 100 percent throttle up to 7k. So what you are sayin is....set everything up for open loop but don't fail the MAF?? So I would tune the MAF first...then how would I go about tuning the VE table?

 

Let's worry about one thing at a time. Let's figure out why you are commanding 12.5 first. Go log a MAF run and post the scan.

 

ok, I'll set it up for open loop...disable cot and dfc, but I won't fail the maf....I'll go do a scan quick

:edit:
I guess it'll have to wait until tomorrow, now this piece of junk won't communicate to download the tune. I tried deleting that vcm suite config file and all....I don't know why it decided not to work and I'm ready to throw it infront of a moving car haha.

 

Damn, dude, your luck is worse than mine! When you do the tune, do it exactly like kennyspec's how to. Just don't fail the MAF.

 

yea, I used his how to for my set up for ve tuning....only difference was I was told to set all the open loop multipliers to 1 all across the board instead of just the last half of them. But I will give that a shot but leave the MAF alone....I already have the tune set up to put in my car, but now my HPT won't connect.....just not my night haha. Hopefully I will get it going tomorrow though

 

with the open loop modifiers, it doesn't really matter which way you do it. You really don't need to change them at all, if the rest of the tune is correct. Wether you command 14.7 under load or 14.2 or 13.8, if your fueling tables are correct, you can tune the MAF. I think most people disable all that so that they can hide fueling errors.imo

I hope you get it working too. I am curious to see what the problem is.

 

hopefully you get it working and figure out whats up


on a side note, what kind of wires did you use to connect the wb to the hptuner box..?

 

I have an Innovative LM-1.....it has the output on the display box and it came with a plug to plug into with with 3 wires, two output and 1 ground.

 

Do you think he's getting grounding noise, Doc?

 

well, I'm hooking the wideband up to the HPT box...I have the hpt pro, so I have the analog input on the box.

 

ok, I did a scan with the MAF sensor enabled......still commanding a 12.5:1 afr....I put a copy of the scan on the HPT forum...


http://www.hptuners.com/forum/showth...249#post105249