Inacurate wideband readings with TunerPro

Holden/Delco Tuning. ALDL, OBD 1.5. Circa 1989 to 2004.
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Charlescrown
Posts: 1831
Joined: Sat Aug 06, 2011 7:58 am
cars: V8 VR Commodore BT1
LB Lancer 2L turbo & Delco
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Mitsubishi Lancer EVO4 track car
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Location: Padstow NSW

Inacurate wideband readings with TunerPro

Post by Charlescrown »

I haven't played around with my car lately but today was the day. Using my LM1 the reading on the screen were looking good around 13 to 15:1. The weird thing was when I play the log back with TunerPro it is showing super lean going well past 17:1. I measured the LM1 analogue output and at 13:1 it was around 1.7 volts which to me sounds pretty accurate. The weird thing is to get such high reading the LM1 should be putting out around 4 volts. Thinking it may be the ECU I tried another and it's the same. Any ideas?
Dylan
Posts: 3355
Joined: Mon Aug 02, 2010 6:35 pm
cars: VR Commodore V8

Re: Inacurate wideband readings with TunerPro

Post by Dylan »

808 or 424?
Charlescrown
Posts: 1831
Joined: Sat Aug 06, 2011 7:58 am
cars: V8 VR Commodore BT1
LB Lancer 2L turbo & Delco
Starion TBI with Delco
Mitsubishi Lancer EVO4 track car
NA MX5
3 vintage motor bikes
Location: Padstow NSW

Re: Inacurate wideband readings with TunerPro

Post by Charlescrown »

It's an 082 and I am using one of VL400's loggers. The logger id displaying the high readings around 18:1 when the LM1 is 13:1 with the output from the LM1 about 2 volts. Really weird. It looks like the ECU is putting out the wrong data but as I said I tried another ECU that I have used before and it's doing the same thing.
Dylan
Posts: 3355
Joined: Mon Aug 02, 2010 6:35 pm
cars: VR Commodore V8

Re: Inacurate wideband readings with TunerPro

Post by Dylan »

You can change the 0 5 volt settings in a scalar in tuner pro to match up with the other gauge, providing it's correct.
And can even remove the pull up resistor on the PCB as well.

Or is the wideband wired direct to the logger?
Charlescrown
Posts: 1831
Joined: Sat Aug 06, 2011 7:58 am
cars: V8 VR Commodore BT1
LB Lancer 2L turbo & Delco
Starion TBI with Delco
Mitsubishi Lancer EVO4 track car
NA MX5
3 vintage motor bikes
Location: Padstow NSW

Re: Inacurate wideband readings with TunerPro

Post by Charlescrown »

Thanks Dylan
I have checked all the scalars and their set right for the ratio and voltage. The wideband is going to the LM1 unit which has an output which is wired to the ECU I think it's pin D8 but will check. The strange thing is it has been working spot on in the past. Will play around today and see what I can find. First thing I will do is use Dicks DST which he has a 12P logging on and see if that also gives me the incorrect reading. Will post updates. Not sure about the location of the pull up resistor.
Charlescrown
Posts: 1831
Joined: Sat Aug 06, 2011 7:58 am
cars: V8 VR Commodore BT1
LB Lancer 2L turbo & Delco
Starion TBI with Delco
Mitsubishi Lancer EVO4 track car
NA MX5
3 vintage motor bikes
Location: Padstow NSW

Re: Inacurate wideband readings with TunerPro

Post by Charlescrown »

Problem solved. I was thinking about the pull up voltage so did some checking earths and found an open circuit from the wideband output. I assume this was causing the ECU to pull the voltage high so I connected another earth and it's the same readings on both LM1 and logger so I an on a high now so it's back to tuning. Thanks.
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