Utilizing your ScanGauge

[markopolo]

I moved this topic from the General Discussion. I think it qualifies as a Tweak or a Modification.

I'll take a magnet & check the pan just out of interest next time I'm under the van.

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Who else has a ScanGauge?
What gauges do you display?

[markopolo]

I've used about half a tank of fuel since I did the initial Scangauge fuel fillup.
It is on the side high compared to my manual records - showing 18.7 MPG on my average fuel economy (TANK trip) gauge.
It will become more accurate when I do the second fillup and enter the exact amount of fuel. That entry will create an "adjustment factor" that the Scangauge will use from that point onward. I will try to remember to do a third fillup and enter it.

[markopolo]

Also, the four gauges I use most of the time are:

RPM - RPM of the engine
TFT - Transmission fluid temperature
FWT - Water/Coolant temperature
AVT - Average fuel economy (TANK trip)

Sometimes I display these:

VLT - Battery Voltage
AVC - Average fuel economy (CURRENT trip)
MPH - Miles Per Hour (when I cross the border)

[WJones]

In addition to the transmission fluid temperature, I would also like to have the oil pressure in my 1999 Express (1999 Roadtrek 200). Does eem to be possible from what I have found.

William

[markopolo]

I have a Xgauge pdf file from 2009 that listed an experimental Xgauge for GM vehicles using the CANSF protocol.

GM CANSF protocol - (experimental)
TXD: 07E0221154(01)
RXF: 046205110654
RXD: 3008
MTH: 00090005FFD8
NAM: OIL (or EOP for engine oil pressure)

It probably didn't work as it is not on their website now. My van uses the VPW protocol.

[markopolo]

My '97 GM diesel van has an oil pressure gauge in the dash cluster. Oil pressure is shown in kPa.
I have a few xgauge codings I will try sometime to see if they return anything and see if they match the built in gauge. (kPa to PSI)

The first one I'll try will be the one noted above ( TXD: 07E0221154(01) CANSF ) but changing the identifier (in bold) to VPW ( TXD: 6C18F1221154(01) VPW ).

[WJones]

markopolo,

I also have an oil pressure gauge in the instrument cluster. Mine is an RT sold in the US originally, so the gauge is in PSI. The reading seems reliable so far, but it is sometimes irregular in its movement, as if it's catching on something. So, I'm a bit worried that if I do lose oil pressure for any reason, that the gauge might get stuck at a normal pressure reading and not tell me - until the idiot light tells me its too late!!! After having the Scangauge for a couple of years I guess I'm getting obsessive about engine readings.

I wasn't aware that the first digits defined CANSF and VPW. Interesting.

BTW, the gauges I use the most are:

KPH - Km per hour (to avoid having to convert MPH to KPH when I'm in Canada)
TFT - Transmission fluid temperature
FWT - Water/Coolant temperature
AVC - Average fuel economy
... but I would drop AVC for oil pressure if available.

William
99C200P
Sherbrooke, Quebec

[markopolo]

Those first digits are the only differences I can see in the VPW and CANSF codes here: http://www.scangauge.com/support/x-gauge/gm-specific/

[WJones]

Marc,

Well, I tried the following:

TXD: 6C18F1221154(01)
RXF: 046205110654
RXD: 3008
MTH: 00090005FFD8
NAM: OIL (or EOP for engine oil pressure)

I also started TXD with 6C10F as many commands for VPW start this way, and I tried with and without the trailing 01. So far, no luck. I get a blank next to EOP.

William

[markopolo]

I just don't know enough about it to figure it out.
I found these two codes on IRV2 for larger Workhorse chassis RV's:

2006
TXD: 6C10F122115C01
RXF: 04620511065C
RXD: 3008
MTH: 007300FF0000
NAM: EOP

2004
TXD: 6C10F1221470(01)
RXF: 046205140670
RXD: 3008
MTH: 001D00320000
NAM: EOP

again, I think the 6C10F1 might need to be changed to 6C18F1

and I found this comment on a forum (can't recall which one):
re: GM VPW protocol - "PID for engine oil pressure is 115C sometimes referred to as 22115C"
You can see the "22115C" at the end of the 2006 TXD so I thought a TXD of 6C18F122115C(01) would be worth a try.

TXD: 6C18F122115C(01)
RXF: 046205110654
RXD: 3008
MTH: 00090005FFD8
NAM: EOP

All just guesses on my part but those were the three that I thought I'd try in addition to the one previously mentioned.

[markopolo]

I tried the oil pressure codes in the previous posts and none worked for me. I have read that oil pressure info might not go to the PCM in lots of vehicles and instead goes straight to the dash cluster and suspect that might be the case in our vans.

My understanding is we're looking for an enhanced mode (mode 22) pid.

I did find some interesting stuff for GM owners here:
http://service.gm.com/gmspo/mode6/
I downloaded 2 pdf files (engine & transmission) of trouble codes for my vehicle. Might be useful someday.

[WJones]

I am getting to the point of giving up on any hope of getting the Scangauge to display oil pressure information for my 1999 Chevy. As did Markopolo, I tried all the codes listed here, and even variations (adding the 01, for example) and nothing worked.

I have a few even more compelling reasons to think the pressure just can't be read by the scangauge:

- There is no trouble code for low oil pressure. If there were one, we would know that the PCM is aware of the oil pressure and I would think that they would have the PCM turn on a "Low Oil Pressure" idiot light to warn the driver. There is no idiot light for low oil pressure specifically.
- In the circuit diagram (Haynes Repair Manual) for the Instrument cluster warning system, there is a wire going directly from the Engine Oil Pressure Sensor to the cluster's oil pressure gauge, bypassing the PCM.
- There is a light in the cluster to warn the driver of low oil pressure, but that is the Check Gauges light. It is controlled by the logic board in the instrument cluster, not by the PCM.

The only fly in the ointment as far as my theory goes is that there is a connection between the Engine Coolant Temp. Sensor and the Temperature Gauge in the cluster, yet the Scangauge does read Coolant Temperature. Is there a second sensor feeding the PCM ???

The Haynes circuit diagram might not be 100% accurate, so I can't be 100% sure that a connection doesn't exist even if I can't see it.

William

[booster]

It was fairly common to have two temperature sensors, one to run the engine and one for the gauge, at least it used to be. The wiring diagram should show two sensors if it has them.

[WJones]

Originally Posted by booster

It was fairly common to have two temperature sensors, one to run the engine and one for the gauge, at least it used to be. The wiring diagram should show two sensors if it has them.

Yep, found it in the manual. 1996 through 2000 models are equipped with a coolant temperature sending unit (which feeds the cluster gauge directly) and an engine coolant temperature sensor (ECT) which feeds the PCM, and of course the Scangauge by the same token.
So far, I haven't found any indication that oil pressure has a second sensor, so the oil pressure sending unit must only feed the cluster gauge. The PCM (and the Scangauge) is left in the dark as to the oil pressure.

William

[markopolo]

I did the second fuel fill-up today to calibrate the ScanGauge. The ScanGauge figured the van had used 50l fuel when in fact the van used 75l. That made for a huge 50% correction factor! My manual calculation indicated that the ScanGauge had over estimated my MPG by 18%.

I suspect I might have to do the fill-up procedure a few times to get it dialed in. This last tank was not the best example as I idled the van a lot and took many test drive type trips trying to heat up the trans fluid, checking the steering etc.

I'm going to miss the reported almost 19 mpg though

[markopolo]

I'd like to have an Hour Meter gauge on my van. I can use my van's engine as a generator so knowing the total run time would be useful info to help decide when to change the engine oil.

Scangauge has an Engine Run Time X-gauge but I think it resets to zero when you when the engine is off. Anyone know for sure?

[booster]

Originally Posted by markopolo

I'd like to have an Hour Meter gauge on my van. I can use my van's engine as a generator so knowing the total run time would be useful info to help decide when to change the engine oil.

Scangauge has an Engine Run Time X-gauge but I think it resets to zero when you when the engine is off. Anyone know for sure?

I don't know for sure, but their other accumulators, related to mileage anyway, keep the data in multiple ways. If it does, you would have the options of current trip, today, yesterday, and tank. You can run tank for as long as you want, so that might work for you, if it keeps the run time the same way.

I did a little looking, and most are saying it is run time since ignition is turned on, so it may not even have to be running to accumulate time. Bummer, total hours would be nice to have.

[markopolo]

I'll try the Remaining Oil Life gauge in my older van sometime to see if it works.



That gauge should factor in idling in addition to mileage for it to be useful I'd think.