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Hi, I'd like to make sure the scangaugeII would display mpg in my vehicle before purchase.
Apparently this 1995 vin code W 4.3 engine blazers are a changeover year to OBDII. Mine is OBDII and I can scan many functions such as fuel trim,O2,mph,rpm,temp, ect. Is there a good chance that the scangauge will work for mpg?
What input does it use? I can read nothing about injector duty cycle or pulses on my basic scanner.

Thanks

From here: http://www.scangauge.com/support/CompatibleVehicles.shtml
"1995 Chevrolet Blazer,S10 4.3"

Looks like you're good to go.

I checked that last night, but didn't want to fall under "info that is not displayed" due to sensors that I didn't have. I also think I'm good to go , just wanted to make sure. Thanks.

Would you happen to know what the sgII uses to keep track of the fuel?

Air flow. It uses that combined with the standard stoich ratio of air to fuel and the displacement you specify for the engine to calculate gas usage based on air volume taken in.

I don't have a maf sensor, so my sg would have to use a few other parameters to determine fuel consumption. There are 5 parameters the ecu uses for determining fuel output...

My car seems to be a lot different in many ways...and they don't seem to be good either...

I believe the SG can use either a MAF or MAP sensor.

Neither a map or maf would be a good choice for measuring fuel. The method described by RLC sounds like it would work, but is still a very poor way to measure fuel. All these methods sound un reliable.

Are we sure it doesn't use something directly involved with the fuel? Injector duty or pulse?

ps I've got confirmation from SC directly that it will work too so that's good news. I am good to go regardless. (as long as it really works)

It isn't the best choice, but it is the one that is most broadly applicable. It turns out to be pretty decent (with some fine tuning) in most vehicles that don't vary the air to fuel ratio -- which is why it doesn't work well in lean burn vehicles (Civic HX, HCH-I with 5spd, Insight with 5spd, diesels). The main issue is that vehicle manufacturers tend to have a wide array of communications protocols relating to fuel management which are not standardized across the industry -- Linear has chosen the parameters which are almost always present and presented in the same way.

For direct measurement of actual fuel usage you'd have to switch to either the SuperMID (built by our own Yoshi), or the MPGuino -- both of which require finding the injector signal to tie into directly. No nice and clean plugin for those devices; you'll need a soldering iron to use either one.

Thanks, I can't wait to buy into the group buy.