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OBD2 PID codes

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#1 ·
i have been setting up an obd2 dashboard on the mx-link/ obdlink and im wondering if anyone has a complete list of "PID" codes for this car.

if not a complete list i would like to find the oil temp/ pressure, and trans temp at the very least.

thanks in advance,
mike.

oh and PS: if anyone has a different free/cheap obd program let me know!
 
#2 · (Edited)
I paid for the Torque Pro app and I can't get some things to display. I am still going to try to play around with it, but supposedly here are the PID's (generic for GM, Pontiac, Vauxhall and Opel)

Oil Pressure: 221470
Oil Temp: 221154
Trans fluid temp: 221940
 
#4 ·
I paid for the Torque Pro app and I can't get some things to display. I am still going to try to play around with it, but supposedly here are the PID's (generic for GM, Vauxhall and Opel)

Oil Pressure: 221470
Oil Temp: 221154
Trans fluid temp: 221940
Which Bluetooth sender are you using?
 
#8 ·
I started out with just the BAFX OBDII dongle and the free version of Torque for the sole purpose of seeing if there really was a heat soak problem with the IAT sensor (integrated into the MAF). Sure enough, it was bad. So I got a heat soak reduction kit and continued to use Torque to be nosy. I got the oil temp and oil pressure to work last night. With stead driving in cool spring temps the oil temp seems to stay 2-3 degrees above coolant temp. Once the car is off (for about 30 minutes), surprisingly oil temps drop fast...engine coolant stays the same and IAT spike high. I can't get the trans fluid temp to report anything, just stays 32ÂşF for some reason.

But I have been digging the 0-60mph and 1/8mi and 1/4mi timers! It uses the OBDII sensors and not GPS, so it is accurate.
 
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#5 ·
I also have the torque app...I use it on everyones vehicles to read and clear codes
 
#7 ·
I've read some horror stories about electrical fires from cheap adapters so I think I will stay away from those $10 ebay units. The one you bought has lots of good reviews on amazon so it looks better from a safety perspective. Looks long, does it fit OK plugged in all the time? I've been looking at the scantool brand ones as those are recommended by the developer of the torque app. They are more money. For $70 you get a Bluetooth one and for $100 you get a Bluetooth one that also supports some additional functions for GM vehicles outside of OBD2. I don't know if those functions are relevant to the SS.


[ame]http://www.amazon.com/ScanTool-426101-OBDLink-Bluetooth-Diagnostic/dp/B006NZTZLQ/ref=sr_1_1?ie=UTF8&qid=1429016539&sr=8-1&keywords=obdlink+mx[/ame]
 
#9 ·
I've read some horror stories about electrical fires from cheap adapters so I think I will stay away from those $10 ebay units. The one you bought has lots of good reviews on amazon so it looks better from a safety perspective. Looks long, does it fit OK plugged in all the time? I've been looking at the scantool brand ones as those are recommended by the developer of the torque app. They are more money. For $70 you get a Bluetooth one and for $100 you get a Bluetooth one that also supports some additional functions for GM vehicles outside of OBD2. I don't know if those functions are relevant to the SS.


http://www.amazon.com/ScanTool-4261...stic/dp/B006NZTZLQ/ref=sr_1_1?ie=UTF8&qid=1429016539&sr=8-1&keywords=obdlink+mx
Yikes! I had not heard about the fires! I am cheap skate though, so as much as I would like $100 top of the line unit, I just can't justify it. Maybe one day. It would be nice to have one that is GM specific so you can read everything with no BS or customization.

Yes the BAFX is long. I have grazed it with my foot when exiting a few times, minor, no damage. I am 6'1" though.
 
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#14 ·
I have performed full pid scans on other GM vehicles (gen 2 CTS-V, cobalt SS/SC & cobalt SS/TC) and found the unpublished IAT2 PID and shared it in the torque forums a couple years ago. To do this, you have to install torque and torque scan plugin, launch Torque Pro and pair with your obd2 adapter, put the key in accessory (which may be difficult to keep in accessory mode for longer than the 5 min shutoff time on the SS), load torque scan, go to menu and PID scanner, menu, start scan and wait for it to complete. There are typically 3000-5000 pids, so it takes as long as your scanner can read PIDs. The cheap elm units typically get 7-15 PIDs/sec. The obdlink mx supposedly get into the 50-100+ PIDs/sec. I have yet to pick one up - but I plan to.

The trick is the output of the PIDs is in hex, which you have to convert to decimal. The tip I have to share is by not having the engine running in controlled conditions (knowing the ambient temperature and the car being cold, all the temperature PIDs will be easily recognizable). IE: if it's 68*F, that's 20*C, convert that to Hex and you have the value approximate of whatever temperature probe/PID you're looking for. Then after a full pid scan, you can email the results to yourself, and copy the output to excel and convert the hex data to find which PIDs are of interest. Then you can setup a few of them plugging the pid register to some copies of the particular temp formulas desired (ie: trans temp), take the car for a drive and see if the values seem realistic. It's completely trial and error, and it took me about 30 tries before I found the factory IAT2 temperature register, but you will eventually find it. Then you can make custom gauges to use and have them flash when hitting a particular temp as a warning indicator.

I know this was maybe too much detail, I'll share more when I finish polishing up my SS that I got a couple weeks ago. I plan to do a full PID scan, what would be all the values of interest? I'm sure the typical oil temp, transmission temp, IAT if it's not already there, timing, kr, coolant (should be available for default).

All the torque PIDs that work by default are helpful, I've easily diagnosed bad coils and injectors by using the misfire counters and swapping coils and injectors around to see if the problem moves to a diff cylinder or not. Torque has been a very helpful tool in many ways. I wish it had been ported to IOS, but there are others now available in IOS that I will play with once I pickup and OBDlink mx wifi.

I hope at helps add some value to this thread! Good luck!

Matt
 
#17 ·
Matt. ^^ congrats on your SS.
Hope to hear more from you as you explore obdlink MX Bluetooth/android in your SS.
I have the MX and torquepro and you are right as you mentioned in your post above... A lot of addtional info is needed in order to get going with it if you want more info than rpm speed .... Generic gauges.
Something I did not know ..... Just having the PID number is not enough to get ECM info.
One also needs the PID formula which may be very hard to find.
Again thanks for sharing.
Paul
 
#18 ·
hi guys sorry about the lag in response (work isnt great right now)

the process to do a full pid scan sounds like a pita but might be the thing that needs doing.

the basic codes im hopeing to get are the trans temp, oil pressure are the 2 im really aiming for. the ability to look at more would be great.

shoot me a PM if you find anything interesting!
 
#19 ·
Purchased the OBDlink MX Bluetooth adapter, $99 from amazon. It paired up in seconds to my phone and I had no issues with communication while testing. Played with the OBDlink software for a few minutes, then bought the torque pro app. Spent 30 minutes today playing with it and determining what parameters I could read in real time. So far, it has worked well. I did find transmission fluid temp in the list and it appears to work correctly. The temp goes up and down slowly while driving. Not sure if outside air temp is working correctly as it didn't change from 87.8 F while mylink was displaying 91-92F. Also not sure is AFR commanded is working as it seemed to sit at 14.08. I could watch the o2 sensor flip around 0-1V, but that's not valuable like a WBO2.

Here is a screenshot of what I got that interested me in the first 30 minutes. This is after a drive in 90 degree weather with stop and go, then sitting still in the sun, idling and ac running, so everything would be heat soaked.

Image
 

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#20 · (Edited)
Thanks for the update guys! My OBDLink MX arrived today and I performed a Full PID scan. Unfortunately, with the engine off in acc mode - I only got a snippet of the full PID's recorded because of the loss of connectivity. After putting the car back into key mode about 5-6 times (30 minutes total scan time) the scan appeared to complete successfully. However, with the first auto key-off - it halted retaining the data.

I'm going to have to perform a full pid scan while running/driving to ensure all PIDs get recorded so I know which PIDs have empty base data and which have measurable/changing data. Needless to say, many of the PID's for use are available with Torque Pro and the Torque Scan app installed.

I agree with Silver Surfer with the Oil Pressure (PID 221470) and Oil Temp (PID 221154), but the Trans Temp (PID 221940) didn't register any data for me on my SS when scanning. PID [0105] did register a value about 6*C higher than my Oil Temp PID. This appears as Transmission Temperature Method 3 in Torque Pro, and may be the PID that works for me.

I read about the OBDLink MX Wifi adapter on Amazon, and it got horrible reviews. Unless you want to deal with some of the issues it has, I suggest staying with the Bluetooth version that many of us have gotten.

I've added the pre-configured PIDs for trans temp, oil temp, oil pressure, KR and some other data populated PIDs found in Torque Scan Pro (base screen) and attached a screenshot (warm engine, not running). I'll observe how all these behave on my morning commute and report back my findings. I think this covers most of the data we'd want.

I do plan to do a full scan and see if I can find the PIDs for tire temps. Apparently RX8 owners have succeeded, and I'm curious if Holden engineered tire temp PIDs. Obviously, we have tire pressure PIDs because they display in the DIC. I need to do a full PID scan on my wifes car (2008 Vue) to determine the tire press on that because they are not displayed in the DIC, but it has TPMS. I've always been curious if they exist in the ECM (side project).

Thanks!
 

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#21 · (Edited)
Seems we picked mostly the same things to watch. As you can see in the screenshot above, I have trans fluid temp monitored and didn't have to create any custom pids to do so. I just tried adding the ones available until 1 worked.

Very interested in what other pids you find.

The system did behave in an odd way last night. I had left it plugged in last night while the car was off. Its supposed to power itself off. At 4am, my phone kept beeping. It kept complaining it was attempting to pair with the OBD2 device and failing. My bedroom is above the garage, so might be close enough for the Bluetooth to see the adapter, but not close enough to establish a connection. Why this started at 4AM is a mystery as the phone had been in the same spot for 8+ hours and the car had been in the same spot as well.
 
#22 · (Edited)
Well - I learned a couple things today.

1) PID 0105 isn't the transmission temperature because it mirrored the coolant temperature (PID 05).

2) Intake Air Temp (PID 0F) appears to come from the MAF and reads much higher than the actual intake air (not even close to Ambient Air Temp). With an ambient air temp of 86*F, the Intake Air Temp was 120-140*f. It is almost like IAT2's on boosted cars in 86*F ambient air. :blink: I suppose the IAT relocation kit is worth it?!?

3) I performed a full PID scan (took about 1 hour) and got some disappointing news. The scan captured 4221 PIDs, but it appeared to skip all PIDs. This seems odd, so I checked with another OBD2 ELM327 Adapter and I had the same results. I'll explain more below:

Here is a snippet of Mode 22 PIDs:
Command: 220001 response:7E8 03 7F 22 12
Command: 220004 response:7E8 03 7F 22 12
Command: 220009 response:7E8 03 7F 22 12
Command: 220010 response:7E8 03 7F 22 12
Command: 220019 response:7E8 03 7F 22 12

Notice 220002, 220003, 220005, 220006, 220007, 220008 and others are skipped? I found this odd, because the skipped PIDs could have data. So to expand further - here are a couple examples of known working PIDs not included in the full scan by Torque:

Oil Pressure - PID 221470:

Command: 221440 response:7E8 03 7F 22 12
Command: 221451 response:7E8 03 7F 22 12
Command: 221464 response:7E8 03 7F 22 12
Command: 221479 response:7E8 03 7F 22 12
Command: 221490 response:7E8 03 7F 22 12

Skipped!

Another example - Oil Temperature - PID 221154:

Command: 221140 response:7E8 03 7F 22 12
Command: 221151 response:7E8 03 7F 22 12
Command: 221164 response:7E8 03 7F 22 12
Command: 221179 response:7E8 03 7F 22 12

Skipped again! :question:
I then went to the Torque forums, and it appears that skipping PIDs is not abnormal. I find this strange because there are valid PIDs not included in a 'Full Scan'.

I've done a brief amount of searching for Transmission PIDs for LS3 PCM/TCMs. I've added Transmission Temp GM Method 1 (PID 221940) and I'll observe it in the morning. For Transmission Temp GM Method 3 - torque has been performing a calculation for Transmission temperatures based off the coolant temperatures instead of finding the true PID (if one exists). Considering Automatic SS's will have a PCM for the transmission, I wonder if the value is in there and passed over CANBUS to the engine PCM? Anyone with HP tuners taken a look at this or maybe tuners have come across it?

Thanks!
 
#23 ·
Well - I learned a couple things today.

1) PID 0105 isn't the transmission temperature because it mirrored the coolant temperature (PID 05).

2
3) I performed a full PID scan (took about 1 hour) and got some disappointing news. The scan captured 4221 PIDs, but it appeared to skip all PIDs.
I got the same results when I tried to scan all the PIDS, everything returns the same value, 7E8 03 7F 22 12.

I do have trans fluid temp working properly, or at least I think I do. The temp reported is the same as all the other fluids in the car from a cold start after sitting overnight. Coolant temp rises pretty quickly, reaching 190+ within a few miles of driving. Oil temp takes much longer to reach full temp, at least 10-15 minutes of driving in 70 degree ambient temps. The trans temp rises still slower. It does not track either coolant or oil temp directly. I haven't seen a trans temp above about 165 and that happens when the car sits while off after a drive while heat soaking. Coolant temp regularly sees 210 and oil temp 215 to 220.

Here is how I got trans fluid temp to display in the torque app. Go into settings and choose "manage extra PIDs/Sensors". Then from the three dot menu, select "add predefined set". In the resulting list, choose "Pontiac/GM/Opel/Vauxhall". That added 2 custom PIDs name "Transmission Fluid Temp (GM Method 1)" and "Transmission Fluid Temp (GM Method 2)" Both refer to PID 221940 and have equation A-40. The only different is the OBD header which is "Auto" for method 1 and "7E2" for method 2. Now these PIDS are available for selection when you add a monitor. Method 2 works of me. On the screen to "add sensor" when adding a display, both method 1 and 2 are green, showing torque is getting data for them. Both show 32 degrees F. If I select method 1 then the monitor doesn't work, it just sits at 32 degrees. If I select method 2, the first display is 32 degrees, but within a second or so it displays a real temperature. Once the monitor is configured, each time I start up torque, it gets readings for the trans fluid temp that are realistic, so I believe they are correct.
 
#24 ·
Hi!

Thank you much nothingtoseehere! You were absolutely right about using the Trans Fluid Temp GM Method 2! I previously tried Methods 1 & 3, but not 2. I see the same results with Oil temp, Oil Pressure and now Transmission Temps as well. With that finding, I believe we've got a pretty good amount of information that isn't shared via the DIC or stock gauges.

Attached are screenshots before and after engine start up after sitting overnight (cold - mind you, Florida in the summer temps):

Ignore the GPS altitude - the car is in the garage.

I'd like to find the TPMS pressure and potentially discover the Tire temperatures if possible. However, without comprehensible data in the response from a PID scan, I'm unsure where to start unless I start guessing at random PIDs. I plan to make a diagnostic screen to include all cylinder misfire counts and any other valuable diagnostic information that is registered by default with Torque Scan with the Pontiac/GM/Opel/Vauxhall extensions.

Question - have you decided where to mount your phone/tablet to display this information? I'm considering this for my spare android phone that I use Torque on:


and then an Invisicord USB charger off the mirror:
Invisicord Products

Any other ideas for permanent, yet discrete mounting location for a dedicated android phone? I'm considering a V1, and that would be best mounted to the mirror instead of an android phone.

Thanks!
 

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#25 ·
Glad you got it working. See below for the phone mount I'm using. This gives me wireless charging, one handed operation, decent visibility and an easy reach from the drivers seat. I personally don't want the phone in my field of view and right now I don't intend to use the phone for torque only. The phone goes with me and I'll load up torque if I want to see what's going on or data log.

Here is a quick data log of cold start after sitting in garage all night (cold being 78 degrees ambient). I then drove 5 miles around town and back home. This was all warmup and in my neighborhoods, so I drove with the flow and was very easy on it.

Quick hits (green, orange and grey lines are coolant, oil and trans temps respectively):

  • 6 minutes of driving to get coolant to full operating temperature. This included 2 minutes of local 50mph road and then mostly stop and go 25-30 mph roads.
  • Over the 13 minute drive, oil temp had not reached full operating temp and was still climbing, but based on the slope of the line it was close to stabilizing.
  • Trans temp never reached stable operating temp either, reaching 135 degrees and climbing at end of drive.
  • Still looking for good measurement of throttle position. In this attempt, WOT shows about 80%.

Image


Image
 

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#26 ·
Found this on the interwebz: I have not tested it yet:

TPMS Tire Pressure
PID: 22C901
Formula for wheel 1 for psi = ((A*1373/1000) * 0.145037738)
Formula for wheel 2 for psi = ((B*1373/1000) * 0.145037738)
etc.

TPMS Tire Temp
PID: 22C902
Formula for wheel 1 for degrees F = (9/5*(A-40))+32
Formula for wheel 2 for degrees F = (9/5*(B-40))+32

Testing Update:
Tested with Windows-based OBDDesk - no data returned - this is probably not a valid PID for us
 
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#29 ·
I checked for 22C901 in the full PID scan and it showed up with NULL, so it's probably not of value. However, there may be others in that range that are of value (22C903, 22C905, 22C906, 22C907, 22C908). I will probably learn the extended PIDs for these values once I perform CANBUS scans and bring up the TPMS values in the DIC.

Thanks for the tips on the formulas!
 
#27 ·
Finally broke down and bought a cheap Android 7" tablet to use with Torque. Fits nicely in front of the shifter, fairly visible, and still easily movable to access the storage compartment.

Image
 

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#28 ·
Further thoughts

So... I got to checking out terminal sessions to the CANBUS as a result of my curiosity regarding the recent FCA Uconnect hack. As a result, I've learned many of the AT & ST commands for OBD2 because the OBDLink MX support it. I'll be picking up a wired USB OBD2 ELM327 module so that I can monitor continuous OBD2 traffic because Bluetooth modules are only able to handle data in bursts and I keep encountering Buffer Full halts (even after filtered tuning). The wired USB adapter will allow for full connectivity without packet dropping due to lack of bandwidth via bluetooth.

I had a revelation (yes, I'm slow at times!) that the extended PIDs we got in response from our full PID scans with Torque revealed all the NULL PIDs (due to the 7F in the response). With that said, all the PIDs that were skipped are suspect to contain data and be functional. I've attached a cleaned version of the full PID scan. I've been able to parse it (omitting the first 8 rows) into excel and I'm going to determine all the PIDs that may have data that are not included in the scan. Essentially, all the PIDs not provided (Hex 0-F) are potential enhanced PIDs.

This will allow us to narrow down the functional PIDs, potentially cross compare any known/mapped PIDs and begin the reverse engineering. When I get the USB ELM scanner, I'll begin trapping communication on the CANBUS to determine if the data points for TPMS pressure & temp are sent from the BCM module to the ECM at all (amongst other traffic). I know that I could switch the DIC from one screen to the TPMS screen and potentially get all the values in one scan session.

This coincides with my curiosity regarding the OBD2 window rollup/rolldown module I got to understand the unlock/lock sequence conversations that result with relaying all four windows to rolldown and rollup successfully based. I plan to get a OBD2 splitter cable to perform this sniffing while allowing the window module to reside on the CANBUS. Below is the thread I updated with that and a quick youtube video showing it's operation. This same module causes the hazards to come on when you open and close the doors (not a bad safety measure when parked on a street).

http://www.ssforums.com/forum/electronics/13170-window-roll-down-function.html

Below are a few primer documents if ya'll are interested:

a complete guide to hacking your vehicle bus on the cheap & easy – part 1 (hardware interface) |
a complete guide to hacking your vehicle bus on the cheap & easy – part 2 (interpreting the data) |
https://cdn.sparkfun.com/assets/learn_tutorials/8/3/ELM327DS.pdf
http://opengarages.org/handbook/2014_car_hackers_handbook_compressed.pdf

As for the devices - I like how you guys have gotten creative with a tablet and phone mounts. I'm considering a mount to the rearview mirror for my android phone for gauge purposes only and a separate mount for my iPhone on the dash. I do plan to get a v1 radar and blendmount it, so I'd like the android torque device to be to the left of the mirror in landscape mode - so I may have to build a custom bracket with parts from RAMmounts.

I'll provide an update once I've made more progress. Thanks!
 

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#30 ·
Hi guys new member, who stumbled onto this post searching for some related data. I've been sorting through the HS GMLAN ARBID's in raw data packets for another project. While I often use Torque [great app], I've also been using other scan tools to generate the GM proprietary ID's or PID's I need. Then rather than using an ELM chip, I started logging the "raw" CAN packets to between ECM, TCM, BCM and such with another CANbus tool. This gets ya all the goodies, like the starter sequence sent from the BCM to the ECM once the key has been authenticated. Who needs keys, we have computers.. LOL...

Anyways my hacking around on some 07 and up HS LAN vehicles has shown anything going to the IPC "Gagues" is being streamed out of the ECM or TCM with specific ID's. Including oil pressure, temps, speeds, and RPM. Some are very fast updates, others are about once per second and seem to be padded for smoother display, like oil pressure. The other thing I've found is OBD-II pids don't always match up with high end scan tools like a Tech 2... So I'm trying to build a list of requests and ID's from raw hex data. About everything I've found to date online is from the Chevy Volt guys. But many of the ArbID's the've found don't line up with the trucks I'm focused on. Would be nice to build a list of vehicles that share common ID sets.

Since someone above was looking for oil pressure, and we know it's not in Torque pids, plus I'd personally like to add it, here is the hidden ways I've found it. I just haven't had time to test any of this with Torque. If anyone can do that and help me figure out the exact scaling math used by the IPC, this would be great..

High Speed LAN Raw Data Packets:

Factory ECM Broadcast Msg -- 0x000004d1 -- 00 00 45 02 e9 2a 00 94 -- Scaling is something like (A*100/256)*2 = oil pressure PSI value.. Also in there at Byte 8 (94) is Fuel Level. (A*100/255) = %

GM PID Requested Oil Pressure Return Msg -- 0x000005e8 -- fe 0b 40 79 25 -- Scaling is (A*4) = KPA. The 79 is engine temp I believe. Don't take my word for it.. I had to request more than one PID so it would send return oil pressure info. Not certain why, but here is the raw "3 byte" OBD message captured that got me to that 5e8 line above.
0x000007e0 -- 03 aa 01 fe 00 00 00 00

Someone please give that try in Torque and post up if it worked or not.
PM me with any questions or comments since I forget to check posts.

Cheers,

-K
 
#33 ·
Since someone above was looking for oil pressure, and we know it's not in Torque pids, plus I'd personally like to add it, here is the hidden ways I've found it. I just haven't had time to test any of this with Torque. If anyone can do that and help me figure out the exact scaling math used by the IPC, this would be great..

High Speed LAN Raw Data Packets:

Factory ECM Broadcast Msg -- 0x000004d1 -- 00 00 45 02 e9 2a 00 94 -- Scaling is something like (A*100/256)*2 = oil pressure PSI value.. Also in there at Byte 8 (94) is Fuel Level. (A*100/255) = %

GM PID Requested Oil Pressure Return Msg -- 0x000005e8 -- fe 0b 40 79 25 -- Scaling is (A*4) = KPA. The 79 is engine temp I believe. Don't take my word for it.. I had to request more than one PID so it would send return oil pressure info. Not certain why, but here is the raw "3 byte" OBD message captured that got me to that 5e8 line above.
0x000007e0 -- 03 aa 01 fe 00 00 00 00

Someone please give that try in Torque and post up if it worked or not.
PM me with any questions or comments since I forget to check posts.

Cheers,

-K
Torque can provide oil pressure out of the box. Its working as expected for me through torque. Go to settings and "manage custom obd2 pids". Add the predefined set for GM. Oil pressure and oil temp are included in that set, both work fine on my 2015 SS. Oil pressure in psi is PID 221470, equation A*0.578.
 
#31 ·
Welcome to the forum kidturbo!