Author Topic: wideband problems  (Read 7947 times)

Offline dan4

  • Jr. Member
  • **
  • Posts: 3
  • BHP: -1
wideband problems
« on: February 27, 2011, 08:59:48 pm »
Hello hopefully someone can help, im used to AEM widebands so i maybe being a typical noob here but....

1) I was going to ask whether my 2nd hand wideband kit, round gauge type, was dead as its been humming since fitting but i see there is an update that will lower the noise levels of this so no worries there, if its ment to do it so be it

2) I pressed the button on the gauge when i fitted it and it switched between afr readout and lamdba readouts fine, now it only displays afr regardless of button pressing but other reading changes below it?

3) The AEM kits im used to are insanely quick and this doesnt seem to react quickly at all....ideas?

4) Sat with ignition on i get afr 12, on a cruise i get afr 12. Maybe the sensor is dead? I am running stock boost on a pretty much stock sr20, it pulls clean at afr 11 but occasionally the gauge will just sit at 9. Again im worried the sensor is dead? Could be linked to problem 3?

Offline rob@vems.co.uk

  • Hero Member
  • *****
  • Posts: 3115
  • BHP: 49
    • VEMS Forum
Re: wideband problems
« Reply #1 on: February 27, 2011, 10:36:38 pm »
1) Humming used to be a sign that it was driving the nernst cell, now it seems they've sorted that.
2) I think the button activation value has been fiddled with there will be an issue with which slot does which and whats shown - its in the VEMSTune software, so check the slots.
3) Its quick enough to control an engine with wide or narrow band feed back so I wonder if 4 is the problem, I've often tested the sensor by breathing on the thing and seeing a quick response.
4) Pull the sensor out of the exhaust and see what value it gives in fresh air.  It may not be the sensor, you need to carefully check the wiring as that may lead to a tricky reading.

Offline dan4

  • Jr. Member
  • **
  • Posts: 3
  • BHP: -1
Re: wideband problems
« Reply #2 on: February 27, 2011, 11:15:34 pm »
Ok been out again and the button switched between afr and lamdba fine this time, how irritating!

Il pull the sensor tomorrow and check it. I work for mercedes and at a recent technical meeting they advised cleaning their sensors (they are the same) with carb cleaner so maybe il try and clean it as well. Before fitting all wiring terminals and wiring protection was checked and nothing obvious. Il check each indivdual wire but i cant see it being that. Tonights runs gave spot on reading or at least what i expected and then after a gear change it reads afr 8 all the way to redline until i cruise and try again. Cruise again afr 12 after a while of driving and i can lean it off until its trying to stall and it doesnt change

Hopefully i can find the problem tomorrow but the kit has only covered about 2k miles and its not impressive, the last 2 aem's ive had have done at least 10k with no problems

Offline rob@vems.co.uk

  • Hero Member
  • *****
  • Posts: 3115
  • BHP: 49
    • VEMS Forum
Re: wideband problems
« Reply #3 on: February 28, 2011, 08:14:36 am »
While you are welcome to come on a VEMS forum and make comparisons with competitors products, do not base you opinion of the kit on sensor life please.
There are thousands of these units in operation and have been for many years, know what condition the sensor was in before you had it will have a far greater effect than the quality of the equipment driving it (the control algorithms have been written to exactly the specification provided by Bosch for this sensor type).
An excessive fuel mixture, oil contamination or fuel additives can coat and or damage the sensor.

Offline dan4

  • Jr. Member
  • **
  • Posts: 3
  • BHP: -1
Re: wideband problems
« Reply #4 on: February 28, 2011, 07:32:59 pm »
not to worry i am no longer going to use it, it reads 20 in free air and covering it with a fuely rag gave afr10 after at least 10sec and then it never returns from afr12 much like operation in my car. I lost faith in it and cant trust it now, im sure there are many of them in operation that work but its not for me. thanks

Offline mattias

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 1075
  • BHP: 41
    • Sävar Turbo Site
Re: wideband problems
« Reply #5 on: February 28, 2011, 09:39:45 pm »
dan4: All the kits out there use a variety of the same Bosch LSU4 wideband sensor that this gauge uses.  AEM, Innovate, etc.. all use it.

If you killed the sensor, how is that a problem with the controlling device?