OBD II ScanGauge II What's Normal?

[Techy-D]

I got a Scan Gauge recently because I've been getting Lean Codes once in a while and now more often (they would clear themselves after a while, but I was worried how often they were happening). This little unit is great for watching my MPG's and other stuff, so I chose it for several reasons.

Anyway, the question at the moment is:
Do other peoples rig jump in to OPEN LP mode when you take your foot off the accelerator? (It seems to happen while going 50 or so MPH and taking my foot off the gas, it reads 9999MPG and goes to OPEN Loop untill it slows down and comes back in around 40 or 50MPG). Other times it will stay closed loop and read 150MPG or so (because I'm coasting of course).

Also, when I clear a Code, and it doesn't come back for a long time, does that mean it's really not happening or does it ignore codes for a while?

Have there been other discussions about what is "Normal" for our rigs? Things like the Ignition advance and stuff like that, to help use as a diagnostic tool? If not, I may need to start writing these things down and start a resource to compare.

Lemmie Know what you guys have found, Thanks!

-----
Horse Power - Appears to show how much you are using. (from aprox.8 up to 190+)
Fuel trim (Short Term) - Sits about ZERO (+-2) when driving. Up to 50 idling.
Fuel trim (Long Term) - Sits around (8 up to 20) also moves upwards when idling, down when driving.
(I only seem to trust the trim on banks 1&2, even though the ScanGauge lets me program banks 3&4) We only have 2 banks?????
O2 Sensor Data (only tested Sensor1 so far) - reads steady (45) till engine warms then jumps around 8-80 after going to closed loop. Again the Xgauge paper shows 4 sensors on each of the 2 banks, but I'm sure we only have 2 sensors on each bank, guess we use #1 and #2???

[rowhard]

Anyway, the question at the moment is:
Do other peoples rig jump in to OPEN LP mode when you take your foot off the accelerator? (It seems to happen while going 50 or so MPH and taking my foot off the gas, it reads 9999MPG and goes to OPEN Loop untill it slows down and comes back in around 40 or 50MPG). Other times it will stay closed loop and read 150MPG or so (because I'm coasting of course).

Also, when I clear a Code, and it doesn't come back for a long time, does that mean it's really not happening or does it ignore codes for a while?


Well, first off, your are saying that you have it in one mode and when you take your foot off of the gas pedal it will change it's self to the LP mode? And when you clear a code, it takes a while to go back to gauge mode. Are you selecting gauge mode as soon as you finish clearing the code? If these are the cases, I'd say (after making sure you have a good connection) that you have a bad scan gauge.

[Techy-D]

Well, first off, your are saying that you have it in one mode and when you take your foot off of the gas pedal it will change it's self to the LP mode? And when you clear a code, it takes a while to go back to gauge mode. Are you selecting gauge mode as soon as you finish clearing the code? If these are the cases, I'd say (after making sure you have a good connection) that you have a bad scan gauge.

Sorry for the confustion. I'm in Gauge mode watching 4 seperate Gauges (one of which is the Open/Closed Loop for the Oxygen Sensors). I know that hard acceleration will go to OPEN loop (per the documents), just not sure that hard deceleration should to that (It does part of the time).

I know I probably should change the fuel filter and possibly the Fuel Pressure Regulator to see if this helps, but wondering if the symptom I'm seing could be a clue to something else.

When I clear a code, I go back to Gauge mode and watch the 4 Gauges again. It may go 6Hours of continues driving with no codes (even stopping the engine and start again may or may not throw a code), but usually within 10min of starting up on the next day it will throw a code (Not always).



Hope that made more sense

[etlsport]

as far as i know the scangauge will not ignore any codes, if it comes back right after you clear it, it will come back on

not sure about the loop... ill have to check it

i think normal ign is 16 at idle

for your mpg.. program a code to show your current trip mpg, it will get rid of that annoying 9999mpg that pops up when you let off or the 4mpg that shows up when you get on the gas

pm me if you have any questions about making your own gauges, ive made a few of my own

[Techy-D]

as far as i know the scangauge will not ignore any codes, if it comes back right after you clear it, it will come back on

not sure about the loop... ill have to check it

i think normal ign is 16 at idle

for your mpg.. program a code to show your current trip mpg, it will get rid of that annoying 9999mpg that pops up when you let off or the 4mpg that shows up when you get on the gas

pm me if you have any questions about making your own gauges, ive made a few of my own

Thanks, that is reasuring that I'm only having a momentary problem once in a while (actually once or twice a day).

Yeah, my IGN is around 16 when idling, goes up to 37 at times when accelerating. I haven't watched it long enough to really figure out a patern. I'm watching a few parameters to see if I can see a change when I throw a code.
I need to build a few gauges, so maybe this weekend. Now I know who to go to if I have a problem figuring it out.

[Techy-D]

So, I've built a few gauges and most seem to do something. :)
HorsePower works - Not all that practical for me, but fun to see it work!

Fuel Trim has Short Term and Long Term, but question is: How many banks does the VX have (I thought it was only 2), but I found on the Xgauge list that there could be 4, and when I programmed them all I get some readings from bank 3 and 4 also (however they are kinda weird readings, so maybe not really fuel trim). Anybody figure these out???
(I'm definitly seeing a trim adjust while idling and going back to zero when driving)

Trans Temperature - Didn't work, but I seem to recall someone said we don't have that. Am I remembering right or programming wrong? :confused:

Has anybody else noticed their LP going from CLOSED to OPEN when Decerating (taking foot off the gas)?

[etlsport]

i couldnt get torque or transmission temp to work either

havent looked at fuel trim.. i assumed it wouldnt work because fuel pressure didnt work.. ill have to try that one

[Techy-D]

I'm still playing with this as I find time. I've come to the conclusion I have a vacuum leak that I will be running down (Hope it's not the Intake???)

Anyone else setup the ox sensors or injector trim as an Xgauge? I'm interested how steady these numbers are for you, Oh, and is the LP going OPEN when you drop your foot off the throttle?

Hey Etl, did you have Hp numbers before you put the PV2 on your rig? (I think I read that you did that recently). I wonder if anyone could see a difference on the Scangauge HP based on changes they made?

[etlsport]

yah! best i ever did pre-PV was 213hp.. best i have done since PV was 228.. but i still feel like i have a bit more to go

[etlsport]

just as i thought.. i wasnt getting readings as good as i should have...

with PV2.. cleaned Green Performance Drop in Filter and a fresh Mobil1 oil change.. i hit 242 HP the other day ;Db;

[Solitude]

just as i thought.. i wasnt getting readings as good as i should have...

with PV2.. cleaned Green Performance Drop in Filter and a fresh Mobil1 oil change.. i hit 242 HP the other day ;Db;

Hows the mileage doing?

[etlsport]

really havent noticed a big change, if anything its very slightly better than before.. still average 14-15.. i am lighter on the throttle now though because of the sound

[Techy-D]

It looks like not too much interest in the Xgauge? Anybody program the O2 Sensor data or play with injectors or find other things that could be programmed? I'm still curious if what I'm seing is normal.

Thanks Etl, it looks like there is an actual HP calculation being run somehow, rather than just giving us a number based on a couple variables. It might be usable in testing wind resistance and such???