Another LC1 logging problem (YES I'VE SEARCHED!)

[dville_gt]

Okay, my problem isn't typical (or at least I haven't been able to find anyone else with the same problem).

I am running a VCM standard and using fuel tank pressure (0411 PCM, no egr or ac pressure) to log my Innovate LC1.

HP Tuners is seeing the correct commanded voltage from the LC1 (i.e. if I flat line the curve at 1 volt it see's right at/around 1 volt, 2.5 see's 2.5, 5 see's 5).

Where the problem comes in is that when I open log works (car off) it shows around 20.6 afr yet HPT shows 22.35 afr (aka 4.98v).

Since LogWorks won't show me the output voltage associated with it's current reading I have to assume it'd be around 4.40v (using default LC1 calibration, 7.35=0, 22.39=5, thus 20.6-7.35=13.25/3.008=4.40).

Wideband only has around 200 miles on it and I did a free air calibration yesterday.

I am using the ([PID.6420]/.3324)+7.35 function (PIC.6420 is fuel tank pressure, i.e. where the LC1 is hooked up). LC1 is running factory default calibration.

I've always heard to trust LogWorks and make HPTuners show the same values. I always thought any error would be due to ground offset (which it doesn't seem like I have (HPTuners showing the same voltage as I command LC1 to output), yet LogWorks shows a different AFR than HPTuners.

Please find the attached CFG file.

[Ben Charles]

Seems you need to adjust your 7.35 number to correspond with your WB. Open up a log using you current formula then open up the same log in another window and change the formula until you get it matching.

[dville_gt]

Seems you need to adjust your 7.35 number to correspond with your WB. Open up a log using you current formula then open up the same log in another window and change the formula until you get it matching.

If that is true then I've been 1.75:1 afr richer than the actual AFR

For example, I've got my VE table setup pretty much perfect with the car showing 14.6:1 afr pretty much across the board. If come to find out this WB error is true then my car is actually 11.9:1 across the board and 10:1 at WOT (when afr is commanded at 12.8:1).

Just seems like that can't be possible.

[Ben Charles]

Well I hope im wrong, but maybe someone else will chime in. My reading was only off .2, yours being 1.75 is alot

[dville_gt]

Do the LC1 and the PCM need to have a common grounding spot?

Right now I have the odbii port ground (pin 4 and 5) and the LC1 grounded at the same spot. After reading through some info it looks like the LC1 heater ground (blue wire) should be grounded separately from the green and white wire (system ground and analog ground) to eliminate the heater circuit pulses.

As far as the other LC1 grounds (system and analogue) I guess I should try to ground them at the same place the PCM is grounded since the PCM is the one getting the 5v signal input and comparing it against it's ground.

Does this sound right, could the difference between the chassis ground that the WB is currently hooked to and the PCM ground cause the PCM to read differently then the WB, and if so why would the PCM have the right flat line voltage when I command the WB to output a flat line output?

[Jabbott]

BUY a new WB. it is not a sensor issue, it is with their cable. I went through so many of these I lost count. Get yourself a AFX and you will have no more WB issues.

[dville_gt]

After a bunch of reading I am thinking the problem I am facing is that LogWorks only reads in %o2 in open air, not AFR. %o2 in open air is like 20.9% or something and the HPTuners is seeing 4.98 (obviously I have some ground offset) which is it's max value (22.35/22.39afr)