scan gauge air fuel connection - SRT Forums

gq4life · 03-26-2009, 12:09 AM

I have Aerforce Scan Gauge & I have a LM-1 air fuel & datalogger. It has the ability to send out air fuel signal to a wire & u can set the air fuel rate to voltage (i.e. 0v=7.35 afr, 5v=22.5)can I hook this wire to scan gauge wire & if so what do I set afr to voltage at?hope my english came out good & u can understand me. LoL

gq4life · 03-26-2009, 02:10 PM

no one knows..
wheres aeroforce?
bahamas maybe?

moreause · 03-29-2009, 12:16 AM

yes it can easely be done

This selection allows the user to enter a conversion for this 0-5v
input, which uses the right pin of the three pin connector. To read raw volts,
enter “001.0” for slope, and “000.0” for intercept. This is the default setting
as well. For example, say you want to input the analog output of a wide band
O2 sensor kit. You know from the kit’s documentation that the output is
scaled such that 0v=10 A/F ratio, and 5v = 20 A/F ratio. The conversion
would then be a slope of 002.0, with an intercept of 010.0. In other words,
voltage multiplied by 2 plus 10 would equal A/F ratio. In this example, a
voltage of 5 would result in 5*2+10 equals 20 A/F ratio. Another common
use for these analog inputs are for MAP sensors.

you just have to confirm you intecept after that
since the lm-1 and gage ground are not excatly at the same point it is possible to have a small voltage offset
you can change you offset to compensate ...because the offset seem to be constant

gq4life · 03-29-2009, 01:38 AM

wanted to use same wire as airfuel gauge since its right next to scan gauge..
af gauge set at 0v = 7.35 & 5v = 22.39

(

moreause · 03-29-2009, 05:29 AM

Quote: Originally Posted by gq4life

wanted to use same wire as airfuel gauge since its right next to scan gauge..
af gauge set at 0v = 7.35 & 5v = 22.39

(

yes but the ground of the gage is the pcm ground (under hood)
and lm-1 ground will be ..somewere inside

slope = (22.39-7.35)/5
intercept=7.35

gq4life · 03-29-2009, 09:14 AM

Quote: Originally Posted by moreause

yes but the ground of the gage is the pcm ground (under hood)
and lm-1 ground will be ..somewere inside

slope = (22.39-7.35)/5
intercept=7.35

oh cool thanxs.. so which ground do I use.. body or pcm ground? & I can't find that plug with 3wires. I think shop lost it on me. can I order new one?

moreause · 03-29-2009, 01:59 PM

Quote: Originally Posted by gq4life

oh cool thanxs.. so which ground do I use.. body or pcm ground? & I can't find that plug with 3wires. I think shop lost it on me. can I order new one?

in a perfect world a would say pcm ground, but it will be trouble some and your not even sure that the output is 100% precise anyway

so just put a it to ground and if there is a sligh offset just correct it via the gage

forcefedjunkie · 03-29-2009, 07:59 PM

Yes, what Moreause said. Slope = 3, intercept = 7.3.

You can purchase one of these wires for $5 plus shipping, but you'll have to contact sales@aeroforcetech.com to order one.

Todd

raul-01 · 04-14-2009, 12:59 PM

Okay.. Kind of on subject. I have the AEM wideband hooked up to my aeroforce byut I am not sure how to program it in there.. Any help with step by step instructions?

thanks.

forcefedjunkie · 04-14-2009, 02:55 PM

Quote: Originally Posted by raul-01

Okay.. Kind of on subject. I have the AEM wideband hooked up to my aeroforce byut I am not sure how to program it in there.. Any help with step by step instructions?

thanks.

The gauge instructions actually use the AEM as an example of how to set up the analog inputs. Slope =2, intercept = 10. I've since found that an intercept value of 9.9 seems more accurate, the AEM output might be slightly off? This basically means that voltage x 2 + 10 will give you the A/F ratio.

Todd

raul-01 · 04-15-2009, 03:31 PM

Oh damn. I see that in the instructions. I will try it out. So 009.9 for the intercept?

**Monster** · 04-15-2009, 03:37 PM

Okay Hmm I should try this with my lc-1. I would much rather run a second scan gauge in the wideband pod.

forcefedjunkie · 04-15-2009, 11:10 PM

Quote: Originally Posted by raul-01

Oh damn. I see that in the instructions. I will try it out. So 009.9 for the intercept?

I found that to be more accurate.

Todd

raul-01 · 04-16-2009, 12:43 PM

Well its working ... But I noticed with that formula on the Scan gauge it reads a tiny bit higher than the wideband. Sow hat do I do to fine tune it? Lower it to 9.8 or raise it to 10?

forcefedjunkie · 04-21-2009, 08:07 PM

Quote: Originally Posted by raul-01

Well its working ... But I noticed with that formula on the Scan gauge it reads a tiny bit higher than the wideband. Sow hat do I do to fine tune it? Lower it to 9.8 or raise it to 10?

If you know it is 0.2 high for example, this could be caused by a difference in the grounds used for the AEM and the signal ground of the Interceptor. To correct this lower the intercept value by 0.2 in this example. If it was 10 make it 9.8. This type of offset is constant throughout the range of readings, so it will now be accurate from 10 to 20 A/F ratio.

Todd