Perplexing PLX !!**??

[flea]

Anyone have any experience with the HyperGround system? For roughly $100 it might be worth a try.

http://www.sunautomobile.com/products_hyperground.htm

http://www.caraudiomag.com/testrepor.../photo_01.html

[jknox]

Oh lord, the audio cable myth people are now going for the performance market.

Copper wire is copper wire. Higher strand counts will make the cable more flexible but provide no other benefit. Cable insulation needs to provide heat resistance, chemical resistance, and abrasion resistance.

Is there a reason to upgrade power and ground on vehicles? Sure. Heck, GM uses a 8-guage fusible link to carry the power from a 145A alternator. Trust me, 8ga is not going to carry anywhere close to that current for very long. But $140 for 12 feet of cable is a bit excessive. I'm sure that they are very nice wires, but come on! They don't say what actual size wire they are using, but you can get 1/0 wire for the car audio market (4000+ strands no less) for $4/ft.

I went to tractor supply and picked up some 4ga battery cables - the 2ft and 3ft ones with 3/8" ring terminals work really well for this. And cost less much less. If you want larger / more flexible, get some welding cable and make your own. The car audio forums have lots of writeups on doing this yourself.

Upgrade, but like most things, do it sensibly.

[Dirty Howie]

Flea

Thanks for all that DVM stuff. I recently bought one but don't really know how to use it properly ...... this info should help me.

Do you really think that fueling bais is responsible for the issues at hand here??????


DH

[flea]

DH, I don't have enough information at this point to draw any valid conclusions. Just wanted to share some info to heat up the discussion again.

My recent data from OL MAF using RHS's bias settings raises more questions than it answers right now. There are still a lot of unknowns with the LS2s so it makes you wonder. Same bias table settings today and the AFR is still grouping around 14.7 (+/- 0.3). Never been able to consistently get it this close in the low MAF table until now. The weather gets cooler or hotter (70 vs 85 F) and I would always get more drift than this ... similar to what others have posted. I have even switched back and forth between the OEM air box and my LPE intake and gone around in circles.

Right now the PLX is consistent for WOT (12.6 +/- 0.2) from 7800 Hz (~3K rpms) on up.

Tonight I'm going have a much closer look at grounds, capacitance, etc.

Just trying to get a handle on this like everyone else.

Flea

Thanks for all that DVM stuff. I recently bought one but don't really know how to use it properly ...... this info should help me.

Do you really think that fueling bais is responsible for the issues at hand here??????


DH

[Dirty Howie]

DH, I don't have enough information at this point to draw any valid conclusions. Just wanted to share some info to heat up the discussion again.

My recent data from OL MAF using RHS's bias settings raises more questions than it answers right now. There are still a lot of unknowns with the LS2s so it makes you wonder. Same bias table settings today and the AFR is still grouping around 14.7 (+/- 0.3). Never been able to consistently get it this close in the low MAF table until now. The weather gets cooler or hotter (70 vs 85 F) and I would always get more drift than this ... similar to what others have posted. I have even switched back and forth between the OEM air box and my LPE intake and gone around in circles.

Right now the PLX is consistent for WOT (12.6 +/- 0.2) from 7800 Hz (~3K rpms) on up.

Tonight I'm going have a much closer look at grounds, capacitance, etc.

Just trying to get a handle on this like everyone else.

Well its nice to know your PLX does work.

Any info that you can share is appreciated........


DH

[Dirty Howie]

I just love OLMAF

Freeway and city cruising close to 14.7 and WOT very low AFR-MAF error.

I'm not sure exactly what NB 02 voltage corresponds to what AFR but looking at my log the volts go around 900 when AFR is around 12.5. Volts definately fluctuate inversely to AFR.


DH

[5_Liter_Eater]

I just love OLMAF

Freeway and city cruising close to 14.7 and WOT very low AFR-MAF error.

DH

But are you sure it's really 14.7? There's the rub. I don't mine closed loop being in the 15's honestly. Better gas mileage and ensures negative FT's. I would like to make sure my WOT AFR's are accurate though.

[Dirty Howie]

But are you sure it's really 14.7? There's the rub. I don't mine closed loop being in the 15's honestly. Better gas mileage and ensures negative FT's. I would like to make sure my WOT AFR's are accurate though.

Bill

Yea......but is it really 15

Seriously I don't know anymore. I may have engine problems, exhaust leaks, bad O2, bad WB sensor, over modded car.........

I just wanted a WB so I could tune properly. Now all I do is try to figure out if my WB is working.....not very productive.

I did a very slight MAF calibration last nite (around 1-2 %) and this morning my AFR is 14.2 and WOT is very rich.

Also, I did the log before starting car and seems like I am way lean......


DH

[VYSSLS1]

im really not trusting these cheap widebands at all...

i have 2 of the PLX meters, and while doing some tuning on my own twin turbo ls1 on monday there was 1.2afr difference between my Autronic meter on my dyno which i know is accurate and the PLX meters,

the PLX was reading 12.0 and the dyno was reading 10.8, both with brand new sensors and both mounted PRE CAT!

i have compared the autronic meter, motec meter and a few other more expansive meters in the past and they all read the same,

i have also noticed big differences on NA cars at WOT between the PLX, LM1 etc and the autronic meter but at lower throttle and closed loop they are pretty close...

[Dirty Howie]

im really not trusting these cheap widebands at all...

i have 2 of the PLX meters, and while doing some tuning on my own twin turbo ls1 on monday there was 1.2afr difference between my Autronic meter on my dyno which i know is accurate and the PLX meters,

the PLX was reading 12.0 and the dyno was reading 10.8, both with brand new sensors and both mounted PRE CAT!

i have compared the autronic meter, motec meter and a few other more expansive meters in the past and they all read the same,

i have also noticed big differences on NA cars at WOT between the PLX, LM1 etc and the autronic meter but at lower throttle and closed loop they are pretty close...

Well thats not really what I want to hear.......

At least it should be reading the same from one day to the next...

Thanks for your input....


DH

[Dirty Howie]

Forgot to mention that I found an O2 wire from one of the rear sensors (think it was driver side) sitting on my header. The insulation was gone in a small area and I could see the pink wires but they looked undamaged.

There are some O2 incomplete status readings in my DTC log I took today:


DH

[domestic rice]

Has anyone else been having problems like this with any other wideband (other than PLX)?

DH I know that mine reads crazy sometimes too. One day I get in the car and get it dialed in almostperfect 12.9, next day its at 10.8, and I'm like WTF!!!!! Hell just the other day it was saying that I had a 13.8 afr at 5500 rpm's, WOT and in 95* wether and had no knock?????

[Dirty Howie]

Has anyone else been having problems like this with any other wideband (other than PLX)?

DH I know that mine reads crazy sometimes too. One day I get in the car and get it dialed in almostperfect 12.9, next day its at 10.8, and I'm like WTF!!!!! Hell just the other day it was saying that I had a 13.8 afr at 5500 rpm's, WOT and in 95* wether and had no knock?????

DR: I don't get swings like THAT !!! But I'm running OLMaf and my Maf error was about 2% WOT. So I leaned it up about 1% and the next day It was rich by about 4%

For the fun of it I am going to set my Bias table to 1.0 Right now it is very heavly weighted to IAT which I would think is good as my ECT only fluctuates 10* while my IAT can vary 25* or more during the same ambient temps.


DH

[Dirty Howie]

If anyone is curious ..... here is a log today with OLMAF and my OLFA table set to stock and DFCO turned back on.

With any amount of MAP/Throttle and speed the WB follows the commanded up and down pretty closely. The MAF/AFR error is 2% or less almost everywhere over 3500hz.

Sometimes I actually think my WB is working............


DH

[jknox]

Sometimes I actually think my WB is working............

Please calm down. Do not worry, I'm sure it will be off again tomorrow.

[jalleva]

DH - My truck just threw codes 1123, and 1153. Could this have something to do with our problem?

[Dirty Howie]

DH - My truck just threw codes 1123, and 1153. Could this have something to do with our problem?

Jelleva

I can't find a 1123 ......

If you mean 1132 and 1153 then sounds like your driver front sensor.

I hate to give definative opinions on anything tuning related. But if a sensor aint workin then its certainly possible.......


DH

[jalleva]

I replaced my stock O2 sensors, and the wideband sensor, retuned and it is now working properly. Even after I return to CLMAF. My AFR stays consistent at 14.7 everywhere, except idle. You may want to try replacing your WB O2 sensor if you haven't fixed your problem yet.

[Dirty Howie]

I replaced my stock O2 sensors, and the wideband sensor, retuned and it is now working properly. Even after I return to CLMAF. My AFR stays consistent at 14.7 everywhere, except idle. You may want to try replacing your WB O2 sensor if you haven't fixed your problem yet.

If you replaced them all how do you know which one was faulty ????????

I have kind of decided to ignore this issue because it makes me crazy

Also my NB sensor seems to follow my my WB. Both fluctuate in cruise state and correlate correctly at WOT.

I have no reason to think the WB is incorrect at WOT which is where I am most concerned.

So in cruise state either my WB is correct and I run at Stoich or my NB is correct and I am lean. Either way I can live with it for now.

I am running OLSD now and my AFR looks good



DH

[jalleva]

I was having trouble with the WB reading lean all the time, or jumping from stoich to lean randomly. I replaced the NBs when I threw a code, and my WB continued to have the same readings. I replaced the WBO2 sensor and retuned and it seemed to work for me.

I have a work schedule that sends me out of town for three weeks at a time, so I couldn't trust whomever needed to drive my truck to monitor it for me while I am away. This seems to be working, but I'll keep you updated.