42 replies to this topic

[colgy]

Just recieved my scangauge and its a good bit of kit
However, I don't fully understand how to program the custom gauges for the Z20LET (turbo), can anybody explain what I'm meant to be doing?
I know Mark managed to display short/long term fuel trim *here* but which bits do you input?

There is generic codes for horsepower on the scangauge website, along with GM VPW and GM CAN (???) for things like torque but are they applicable???

Would be gratefull if anybody could explain it without resorting to hexidecimal!

Edited by colgy, 27 December 2007 - 07:09 PM.

[oakmere]

I have added the BHP Gauge and long term / short term fuel trims using Mark's page and they all work. Easy to input following the instructions provided. What I don't understand is how Mark found the alpha numeric strings for the fuel trims??? Mark ??? Also I don't know if the items listed on marks page are the only values available It would be nice to have a torque value if only to compare values before and after modifications. As for the code list on the website I don't know if any are available (as stated earlier the BHP for all vehicles works). Mark is probable going to be the person to ask or contact scan gauge via e-mail. Not much help sorry. Cheers Oakmere

[markv]

Well, programming an xgauge is the easy part Determining what to put in there is the other bit. I think programming is explained quite clearly in the manual. From main you choose:

MORE>MORE>MORE>XGAUGE

Select the gauge you want to edit and press the button referencing edit.

You will then see the different items that are listed on my webpage. You just have to take your time and input all the numbers (correctly!) that are in there.

After you've saved the gauge you can choose to display it in the gauge screen.

On what's available, it is quite easy. Basically everything you can read out through the OBD port can be displayed. However, I think there might be an issue with some commands as they send back long lists of information. I don't think the scangauge is happy with that.

What is shown on my page are the normal PID's that are available on the 2.2. See this as the publically available information. This might be different for the turbo, I don't have any experience with that ECU. There are also vendor specific commands that you can use to retrieve information. However, it is generally pretty difficult to find these out.

For the fuel trims, that is a publically available item as you can see in the list, pid 6 and 7. If you search a bit, you will find the value it returns (see http://en.wikipedia....ki/OBD-II_PIDs). You can read these from the ECU and do some math. I emailed scangauge support for the exact specs for all the fields. If you know them it's just a matter of formulating the strings and see if it works. But be preparred for some low level hex and bit shifting

On the torque bit, I don't have much faith in the generic HP display item. From what I've seen the scangauge calculates the amount of fuel the engine is going to inject, based on the same parameters the ECU does. It than calculates the amount of energy in the fuel injected which is given back as the HP display item (I might be a bit off, but I guess that is the way it works).
I don't think you can reference multiple values in an xgauge. You would need RPM and HP to calculate torque based on this HP value...

Mark

[oakmere]

On the torque bit, I don't have much faith in the generic HP display item. From what I've seen the scangauge calculates the amount of fuel the engine is going to inject, based on the same parameters the ECU does. It than calculates the amount of energy in the fuel injected which is given back as the HP display item (I might be a bit off, but I guess that is the way it works).
I don't think you can reference multiple values in an xgauge. You would need RPM and HP to calculate torque based on this HP value...

Mark Torque was mentioned because it is available for some ecu types on the scangauge x-gauge list:

http://www.scangauge...pdfs/XGAUGE.pdf

Cheers Oakmere

[markv]

The codes that are mentioned for torque are probably for ECU's that are on a car with an automatic gearbox. It will probably need to know the torque the engine is putting out for shiftpoints and clutchcontrol. I tried the mode 22 pid 19 de on the 2.2 ECU, and it doesn't seem to know it. It does seem to know the one for elapsed time since engine start, knock retard, barometer v8 (probably MAP, returns $fb with engine off), a/f ratio (this could be interesting ). Only looked those up on the ECU, not with running engine. So you might give those a try Mark

[oakmere]

[quote name='markv' date='Dec 28 2007, 13:31 ' post='677412']
The codes that are mentioned for torque are probably for ECU's that are on a car with an automatic gearbox. It will probably need to know the torque the engine is putting out for shiftpoints and clutchcontrol.

I tried the mode 22 pid 19 de on the 2.2 ECU, and it doesn't seem to know it.

It does seem to know the one for elapsed time since engine start, knock retard, barometer v8 (probably MAP, returns $fb with engine off), a/f ratio (this could be interesting ).

Only looked those up on the ECU, not with running engine. So you might give those a try


Sorry to be a bit thick about this Mark but do you know the TXD, RXF,RXD & MTH for the air/fuel ratio as it would prove usefull to check if the car is running lean after modification??

Cheers Oakmere

[colgy]

Cheers guys! Just found a more up to date manual at the scangauge website - it tells you how to program the trip functions (like max speed, max water temp, fuel figures etc.) into the gauge display Only thing is - when two functions have the same number, how do you know which is which??

[markv]

I tried the AFR yesterday when I took the car for a spin. From what I see on the display I am guessing this a calculated AFR that the ECU made up. If you look at the programming codes, you see that there are no maths aplied to the number on the display. When starting the car it displays:

147

Which sounds like a VERY familiar number if you assume this decimal and divide it by 10 : ) (AFR)
When driving around the number does not change while driving closed loop. I know this ECU is pretty ok in keeping the fuel correct, but this ofcourse is ridiculous When I floor it and get out of closed loop I see the number change to something like 132 (don't remember exact number).

So it does do something, but I don't know if it is actually usefull. Good chance that when your engine is really running lean and this number shows it running lean, the ECU will already have logged an error code.

Mark

[oakmere]

Thanks Mark Looking forward to the additions to your scangauge page. Oakmere

[colgy]

Tried the Air/fuel ratio for VPW & also for CAN but neither worked on the Z20LET Mark, how did you find out which parameters are available for your engine? How do you know which data stream to send and how did you derive the list of PID's which are available?

[markv]

Tried the Air/fuel ratio for VPW & also for CAN but neither worked on the Z20LET
Mark, how did you find out which parameters are available for your engine? How do you know which data stream to send and how did you derive the list of PID's which are available?

Not sure what the ECU for the Z20LET uses, but the one for the 2.2 uses the KWP2000 protocol with fast initialisation (ISO14230). Also don't know if the AFR pid in mode 22 is available on the turbo and if it will be very usefull..

The standardised pid's in mode 1 are fully documented, you can look them up here:

http://en.wikipedia....iki/OBD-II_PIDs

You can see that part of the setup is seeing which pid's are available, just like I wrote on my website..

Mark

[oakmere]

Mark Have you got the o2 sensor voltages working mine both give a reading of 0.00V? Cheers Oakmere

[markv]

Finally updated the page... I split it of to a seperate one.

I've made some changes to the existing xgauges, added a few new ones and also added some comands.

http://www.verboom.n...016/xgauge.html

Remember, I drive a 2.2, so no telling what this will do on a turbo or other car for that matter. If somebody has any feedback on stuff working or not, please let me know.

Cheers,

Mark

[oakmere]

Thanks mark I will try the o2 sensor gauges again + a few of the others and will give feedback. I have a 2.2 not a turbo. Thanks once again for your input with this. Cheers Oakmere

[oakmere]

Just to let every one know with the scangauge I have tried all the gauges on marks page (apart from time cell light on and the open/closed loop mode as my scangauge already had this as a standard gauge) and they all work on my 2.2. Cheers Mark Oakmere

[VIX]

Probably a daft question but is the ScanGuage Manifold Pressure reading the same as Turbo Boost? PS Sorry, and did you pay £111 for it?

Edited by VIX, 11 January 2008 - 08:57 AM.

[markv]

I don't think the ECU from the turbo uses MAP but uses MAF. Ofcourse, on the 2.2 you don't have a turbo.. Mark

[james141]

anyone know if it is possible to get oil temp on the 2.2?

[mandarinvx]

anyone know if it is possible to get oil temp on the 2.2?

I'm fairly sure the Z22 doesn't have an oil temp sensor, just a coolant temp one. You could add one in the sump, but that would need to be connected to a separate gauge

[RMC]

That is an intersting piece of kit. How easy is it to install?