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- Technical (https://www.ausjeepoffroad.com/forum/forumdisplay.php?f=172)

- - Scangauge Loop Display (https://www.ausjeepoffroad.com/forum/showthread.php?t=94954)

Scangauge 4.0l i6 Open/Close Loop Display

Whos got a scan gauge or similiar ???

Who knows the 4.0l i6 coolant temp when the open/close changeover is displayed ???

C'mon now ... Dont be shy :p ... select the LP display setting instead of some useless tripmeter function gauge display :roll:

.... and tell us what you see 8)

Piccies would be good

One proviso .... :(

From a cold start ;) ..... not the 2sec open loop display from a hot startup :p

Just on the offchance someone has some proper OBD1 reading gear ... It would probably be best for a post layout like this:

XJ Year Model: .................................
Computer Type (OBD I OR OBD II) .......
Coolant Temp at Loop Changeover .......

Pics of scantool display and dash temp gauge if scantool doesnt display coolant temp.

Grrrrrrrr.........

NOT HAPPY MR WOODERS ..... :evil::evil::evil:

When I inquired about the purchase of a scangauge and their actual usefulness ...

You told me they were GREAT ......

..... and evvveerryyybodyyyy had one .... :rolleyes:

...................:monkey:

....................http://www.smileyhut.com/laughing/rofl.gif

Aaaaahhhh ....

Thankyou Mr Rodgebone ..... :cool:

Quote:

Originally Posted by Rodgebone

mornin Carves,
ok, just checked loop switching this morning while the car was bone cold. the scan gauge reported a switch to closed loop at 30 degrees C after only 30 seconds of idling after initial startup. i verified that temp reading against the laptop software and it was pretty close although i had a 50 second lag between unplugging the scan gauge and connecting the laptop to the car and validating the pids. based on the rate of temp increase i monitored on the laptop over 50 seconds, it looks like the scan gauge was pretty accurate (within 2-3 degrees variance at most). obviously the cat was no where near heated up to its 2500 degrees F operating temp at this point, but as i mentioned, heated o2s begin functioning at roughly 350 degrees C. as well, the obdII drive cycle had not been completed either. so what does this show? nothing other than the cars computer begins using the actual o2 signal output to help determine a/f ratios (versus a pre-programmed value) after only 30 seconds of run time. so open loop hangs around only just long enough for the engine to get past that inital cold start (or "choke on" phase). temp in the garage was 24 C while i did the testing. i cant export the actual graphing although with some effort there is a way to export a table of values in word excel but would mean nothing to most folks so no point in going there.

So theres an initial score for 30'c and some good general info for folks that wants it.

Also shows that the OBDII change over temp is not an indicator of O2 sensor condition ... unfortunatley :(

Who else has got what ??? :)

Not ran the Jeep over the weekend. I'll keep an eye on today to/from work. No specific temp is given in the FSM. It just states that once a certain temp is reached and a timer has expired the loop changes. By that I presume the temp may vary at change over.

Missed the change over temp on the way to work as I was just getting into a gap in traffic, looked down and temp was 22°C with loop changed already. On the way home from work loop changed with 19°C shown as temp. Temp then changed to 21°C. Starting temp was about 6/7°C each time. Voted on the poll - only one so far.

Thanks for the input Jonny Jeep. http://www.freesmileys.org/smileys/smiley-happy088.gif

Just for interests sake ..... and at an idle from cold start -> to warm up -> to run modes.

You may notice the revs drop at your 19'c - 22'c change over temps.

Just something else I've noticed when I payed attention.

I was hoping your temps may have been higher before the loop change occurred as I had a brain fart recently .... and wondered whether hot and cold location XJs may have different presets.

One fella reckoned it would be easy to do at dealer predelivery ... and I figured that may have offered a balanced resolution to the, Yes / No ... 195'f thermostat / hot running temp situation.

But going by your temps .... That idea probably wont fly.

http://www.freesmileys.org/smileys/s...atdrink004.gif

my scangauge shows closed loop when first started then goes to open loop somewhere between 20 deg C and 40 deg C, which is way below the 92 deg C (195 F) standard thermostat.

according to some forums it is suggested not to use a 160 F or 180 F stat as it would remain in closed loop all the time. clearly this wrong according to the scangauge

this is for my TJ BTW