Different WB Controller on the Way

I can't honestly remember who turned me onto it but I started checking the JAW (just another wideband) out on http://www.14point7.com. I decided to get a JAW unit because it's cheap and it uses the same Bosch LSU 4.2 sensor that the AEM does (and I believe the PLX and Innovate do). With it I will be able to troubleshoot the problem I have with the AEM reading ~15.5:1'ish in closed loop. The JAW allows for free air calibration (the AEM and I believe PLX do not) as well as giving you data on the heater value of the sensor so it is easier to tell when the sensor is giving up the ghost. I just ordered it and I just ordered the bosch connector from tech edge in Australia and have a lot of work ahead of me when the parts do arrive but once I get it up and running I'll be able to see if I get different readings from it with the same sensor and then see how they change afer calibrating it. I really think the problem lies there (no free air cal ability).

Good luck Bill, let us know what transpires. :) I switched to the AFX from AEM and to the NTK sensor versus the Bosch LSU4, the AFX has free air calibration as well.

I am not to concerned about free air calibration though. As I was explained, why would you want to recalibrate a sensor that is wearing out or contaminated. I think of it like a digital (vernier) caliper, once it is off you do not re-adjust it to read properly by swaying your display. You mearly check it with calibration gauges to see if it is going out of tolerance, if it is you replace it. This point of view was brought ot my attention not by AEM though, although they share the same reasoning. That is just how I view the wideband free air calibration. Just my thoughts, and as I said I am not too concerned about having (or not) free air calibration. :)

I see your point but I just feel better having it. My dad just got an LC-1 that was supposed to be cal'ed out of the box and when he did the free air cal it changed significantly. To use the digital caliper analogy, every time I use it I reset the zero so I think of the free air cal the same.

I am totally subscribing to this thread as I am a little concerned with the difference between open/closed loop. My scanner and software is in the mail so hopefully I shouldn't have to wait too much longer to get a jump on things.

have you gotten the JAW yet? i have one, and will be installing it friday and wanted to see how its working for you.

hopefully ill get my usb to serial adapte by then, because it seems like i need to install software on this thing to output the correct signal to my EGR....not 100%

I am also interested to see how this works. I might get it just to try out a calibration on the sensor and see how accurate the PLX is out of the box.

So you have to get the unit and the display separate? the prices at the top of the page dont match the prices at the bottom where you add to basket. So you have to buy and adaptor as well so you can hook upto the actual sensor?

Haven't gotten my JAW and display yet. Also still waiting on the correct connector for the LSU 4.2 sensor that the AEM and PLX use. He's going through a transition right now I think, only selling the PCB and chips and providing a list of all the resistors and caps you need which may be why the prices are not jiving.

Well I got my JAW working. I used the same sensor and wiring harness from my AEM. Unlike the LC-x's that take an average of the calubration value over as much time as you'd like to calibrate for, the JAW just does a point in time calibration. I did the free air calibration on the JAW many times. The neat thing about the JAW is that you can read the calibration value that it took. You can also see the heater values and know when the sensor is fully heated up. The bad thing is that since it's a point in time I got many different values. Anywhere from -4 to +4. Changing the calibration by one digit makes a notable difference in the controller's output so I don't dig this too much. I took the calibration many times and averaged them and arrived at -2.

So with the JAW controller and the same sensor that came with my AEM I'm dismayed to say that I still am seeing ~15.5:1 (or higher) in closed loop...:banghead: I'm still playing with my custom PID to make HPT match the JAW's AFR but attached is a datalog from the JAW itself of me idling in the garage for ~20 seconds.

So this experiment rules out the controller as a source of the problem. I guess my next step is to try another WB sensor.

I found the AEM sensor for $57.75 shipped at theperformancedriver.com so I pulled the trigger. Should know whether it changes the closed loop AFR when it comes in about a week from now.

BTW: AEM part #30-2001 = Bosch part #0258 007 206 = PLX Type B

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Originally Posted by 5_Liter_Eater

I found the AEM sensor for $57.75 shipped at theperformancedriver.com so I pulled the trigger. Should know whether it changes the closed loop AFR when it comes in about a week from now.

BTW: AEM part #30-2001 = Bosch part #0258 007 206 = PLX Type B

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Bill

I just found this thread because you posted on my old Perplexing PLX thread.

I'm glad you decided to solve this issue with a step by step differential diagnosis.

If the new sensor still shows lean, you can borrow my gun to blow your brains out :banghead: :D

:cheers:
DH

OK, are you guys ready for this? To recap I was ~15.5ish or higher in closed loop with my AEM controller and sensor so I switched to a JAW controller using the same AEM sensor and was still lean, actually more than 15.5, the AEM could have also been leaner than 15.5 but I don't have data on the AEM anymore. So then I swapped in a new sensor and....

...Same thing.

Attached are screenshots (my logs are hard for others to look at since I pipe the WB through the AC pressure) of the chart showing the narrow band cycling and a histo I created of average AFR. I commanded each RPM point with VCM Controls for ~10 seconds to get these averages which you can see are into the 16's...

So I can conclude that there is nothing wrong with the WB controller and nothing wrong with the WB sensor. I got to looking at the WB bung that I had welded on and it is pretty bubble gum'ish because it was welded on while the headers were on the car. It may not be air tight which could be making the WB read lean. I will try moving the WB to one of the NB ports on the headers which are very good welds, although not easy to get at without removing the header. It will take a while to report back because the car is going to be laid up while I install an ECS blower kit and cam. If moving it to a known good bung doesn't do it I'll have to conceed that the narrow bands are switching at the wrong voltage in thier current location and have to cross my fingers that the next version of HPT will fix the bug where changing the switchpoints on a Gen 4 doesn't have any effect.

Now time for a :chug:

Thanks for the update. As another AEM UEGO user I am glad to see that it does not appear to have been in error. Good luck with the blower install.

Well, I didn't switch the WB to one of the better looking NB bungs but I did put soapy water on the WB bung and started it and there are a few pinholes. Definitely not air tight. What efffect that has on the WB and to what degree I'm not sure. The teardown has begun for the blower cam and Paxton so we'll have to wait and see.