Potentially Pointless Puzzles, Ponderings and Perplexments

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
Elsewhere on GMTNation and straying off the topic of that titled thread...

A post in thread 'P10 PCM 5 Volt References' https://gmtnation.com/forums/threads/p10-pcm-5-volt-references.21534/post-634636

All that being said,,, a wondering of mine is unaddressed....

"why is there a negative voltage relative to chassis/frame/signal ground seen on both leads of a CKP sensor?"

The voltage relative to PCM/frame ground is always nearly identical on both leads and I have seen it vary from -2.39 volts right after initial power-up up to -11.33 volts this morning after maybe 24 hours of 'operation'.

These observations of mine suggest the negative voltage strays higher as the PCM is left powered up but idle for longer times perhaps.

There is a 4.5 millivolt voltage seen between the two PCM CKP leads, and the resistance between the two leads when unpowered is in the range of 48 or 49k ohms in both polarities.

Some qualifications are: the subject PCM is powered up on the benchtop with no other connections but serial data and a single test lamp on a single fuel injector control terminal.

Unrelated.... If I repeatedly touch either lead from the PCM CKP sensor terminals, every now and then the test light on the fuel injector control wire lights up indicating fuel injector activity. This was unexpected.

Maybe at some level there is an attempt at isolating the CKP signal from possible electrical noise/interference? And the voltage I am seeing is just some stray anomoly? The voltage is steady and looks pure on a toy/hobby scope.
 

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
It is within the realm of reason that I am losing it!! :wink:

Now when looking again at it I do not see a negative potential to ground but a positive voltage.

I can only conclude that I somehow repeatedly got my leads mixed up?

Hrrmmm.
 

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
So all this looking at CKP (and knock) sensors came about as a result of testing the various PCM terminals labeled "Low Reference" in wiring diagrams.

I discovered these 3 sensors "low reference" designations are unlike all other such "low reference" terminals in that they do not appear to have a low resistance to chassis/frame ground and they actually have a voltage present relative to ground when the PCM is operating. These 'pseudo' low reference terminals are only low in relation their mate and even then it is only a few millivolts lower.

My takeaway is to hopefully remember if I ever have to troubleshoot one of these sensors I must not think of these "low reference" terminals as I would any other sensors low reference terminal.
 

budwich

Member
Jun 16, 2013
2,027
kanata
Not sure that I understand what you are trying to do. IF "low reference" was tied directly to ground, it would have been designated as such. There is likely some form of isolation being done in the circuit. As a result, it is likely that measuring a voltage with a reference to ground can result in some form of voltage being seen IF the point in question is not grounded. Its scale will depend on the circuit design. I would think that this is much like hot and cold design of "normal" AC electronics..... but alas, maybe I am missing something. I would think, for the circuit itself, it is more important for the system to get its reading with respects to its "internal references" which it has "design control".
 

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
In a Nutshell:

(1) CKP Sensors are NOT "True Sensors".

(2) CKP Sensors CREATE Variable A/C Voltage, so taking DC Current Readings are irrelevant.

(3) CKP Sensors require 2 Wires at minimum, so the exited Electrons in the Fine Wire Coil can Flow (Alternate) in BOTH Directions within the Fine Copper Coil Wires as the Magnetic Lines of Force move (cutting) through them, depending upon the positions of the Peaks and Valleys shaped into the OD of the 58 Tooth Reluctor Wheel on the Crankshaft.

(4) CKP Sensors CREATE A/C Sine Waves that WILL Vary in Frequency and Amplitude, depending upon the Increases or Decreases in the expected "Constant Velocity" of the Rotating Crankshaft powered by 4 Stroke Combustion.

(5) When a CKP Signal Wire is attached to an Oscilloscope, it will measure the Increase and Decrease in the A/C Signal Frequency and Amplitude... in exquisite detail.

The Image below demonstrates that at times, the Crankshaft will actually Speed Up or Slow Down, depending upon whether the Piston(s) are under Compression or ...Ignition and Power Strokes. Only an Oscilloscope is capable of capturing the requisite High Sample Rate necessary to visualize these subtle variations in A/C Voltage occurring over Time. Digital Multi-Meters will not work here, because they only display an Average of their Output Readings after taking many fewer samples:


gt017-example-waveform-01.png

(6) The CKP "Sensor" is NOT alone among other A/C Generators using Two Wires at minimum. The others are The Wheel Speed Sensor and the Vehicle Speed Sensor mounted on the Central Drive Take Off Shaft where their "Tone Rings" register A/C Voltage inside of Fine Wire Coils wrapped around Permanent Magnets. They reliably register changes in the Rotational Velocity of their "Tone or Reluctor Rings" moving by Mechanical Energy that must be changed to Alternating Current to be able to measure the subtle increases and decreases in their A/C Frequencies and Amplitudes.
 
Last edited:
  • Like
Reactions: budwich

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
Not really trying to 'do' anything there, just exploring to see what I may learn.

Of the other low reference terminals the Fuel Level, APP sensors #1 and #2, Fuel Tank Pressure, Intake Air Temp, AC Refrigerent High Pressure, Engine Oil Level and Temperature, MAP, Engine Coolant Temperature, Transmission Fluid Temperature, and Throttle Position Sensors #1 and #2 all measure 0.2 Ohms to ground.

The Cooling Fan Speed, Camshaft VVT Solenoid, Knock Sensors #1 and #2 and the Camshaft Position Sensor measure 0.0 Ohms to ground.

The Crankshaft Position Sensor measures 25k to ground in both polarities .

The above are all measurements of several P10 (2002 to 2005) PCMs.

On a 2006 P12 PCM the CKP low reference measures 129k or 105k depending on polarity to ground and the knock sensors are 157k or 100k to ground, again depending on polarity.

Not surprising differences between different PCM models I guess.

This revisiting of the 5 volt reference circuits began when elsewhere on the web someone posted a list of codes they had. Among them were a low MAP signal voltage and a low fuel tank pressure signal voltage as well. Many would immediately jump to thinking it was something taking low a 5 volt circuit. But those two sensors do not share a 5 volt circuit. Seeking to learn a little more I thought I would have a look at the corresponding low references to see were they perhaps segregated or were they all the same low reference. That is how I fell into this rabbit hole.
 
  • Like
Reactions: mrrsm and budwich

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
(2) CKP Sensors CREATE variable A/C Voltage, so taking DC Current Readings are irrelevant.

(3) CKP Sensors require 2 Wires at minimum, so the exited Electrons in the Fine Wire Coil can Flow (Alternate) in BOTH Directions within the Fine Copper Coil Wires as the Magnetic Lines of Force move (cutting) through them


This I understood already. The bit that I find puzzling is what is the purpose of the PCM applying a voltage across this circuit? A voltage differential applied by the PCM across the "fine copper coil wires"?

Not being an electrical engineer or even a technician I would have expected to see nothing there, either relative to ground or each other.

I hooked a little toy/hobby scope across the two PCM CKP terminals and saw the low voltage there is not at all steady but instead varies rapidly and is amplified by my touching either of the y
terminals. I must admit it makes me grin every time I do this and see the fuel injector circuits activate!

Perhaps it is just an artifact of whatever circuitry does the reading of the signal.
 
  • Like
Reactions: mrrsm

azswiss

Member
May 23, 2021
860
Tempe, AZ
The bit that I find puzzling is what is the purpose of the PCM applying a voltage across this circuit? A voltage differential applied by the PCM across the "fine copper coil wires"?
One possibility is that the PCM applies a voltage as an offset to move the voltages into a specific range, analogous to adjusting the vertical location of a signal on an oscilloscope.
 
  • Like
Reactions: mrrsm and TJBaker57

Mektek

Member
May 2, 2017
656
FL
I'll hazard a guess and say this is how the PCM determines the sensor is present during initialization tests before the engine is running. An open circuit would indicate a fault.

Another oddity with the voltages is in the underhood light. It floats at 10v until a low impedance load is applied and then it goes to 12v. I have to modify my LED light to run on 10v for full brightness.
 

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
Another oddity with the voltages is in the underhood light. It floats at 10v until a low impedance load is applied and then it goes to 12v. I have to modify my LED light to run on 10v for full brightness.

I have that light. Currently unplugged due to the unreliable gravity switch and my being unaware of its' power source being the BCM. I thought it was fed direct from a fuse somewhere so I unplugged the harness when the switch proved unreliable and I thought it may be on with the hood closed!!

I see now that underhood light shares its' power feed with the reading lamps, vanity mirror lamps and the glovebox lamp. BCM Connector 3 terminal B18. These all have some form of switch also. Now I am wondering if the BCM turns off the power to this circuit under certain conditions to prevent battery drain when parked overnight or such.
 
  • Like
Reactions: mrrsm

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
Amen, Tom...

 

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
Hmmm... I was just thinking... If Bad or Worn Bearings on the Mains' Journals adjacent to the Crankshaft at the Position where the 58 (60 -2) Tooth Reluctor Ring is attached were creating an excessive "wobble" as well THIS might change the delicate critical alignment and precise distance needed in between the 'tip' of the CKP A/C Coil and its Permanent Magnet Pick-Up vs. the Reluctor Wheel Teeth as it rolls around underneath. And thus... THIS phenomena SHOULD show up on-screen when using an Oscilloscope while Back-Probing upon the CKP Signal Wire.

The same Idea would apply while examining any 4.2L Engine Suffering from Excessive Vibrations at Idle with Bad Motor Mounts, since the Reluctor Wheel WOULD necessarily also have to be Vibrating Excessively at its Outer Orbit... perhaps just enough to Register these changes in the Minute A/C Signals Trace on an Oscilloscope after Back-Probing the Signal Wire of the CKP and then viewing the subtle A/C Field changes as it "wobbles" about with very fine detail... Hmmm :>)
 

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
Regarding the comments-questions from @TJBaker57 posed in Post #7... I'm not certain whether this next information will add ...or detract... from finding the sought after answer(s), but ...FWIW... By 'shifting gears' over to examining a well-known Engine Builders Publication for GM Gen III LS Motors, be advised that The Book's Author dedicated an entire Chapter to the subject of Capturing Crankshaft vs. Camshaft Rotation relationships for the purposes of Ignition Timing and EFI Control ...AND... he refers to PCM Wave Forms specific to certain PCM Calibrations involving both 24x vs. 58x Reluctor Ring and CKP Sensor Pick Up applications:

The Full Chapter On Topic Excerpt from THIS "LS Labor Of Love" is found in an On-Line Article Linked Below. (NOTE: The Original Author gave permission to this Web Page to re-publish the segment and is so cited below):

https://www.lsenginediy.com/crankshaft-camshaft-signals-guide/

1676454096113.png
 
Last edited:
  • Like
Reactions: TJBaker57

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
So my ponderings of today involve the TPMS relearn.

To enter the relearn mode we use the service (park) brake, the lights switch and we hear the horn. All of these are BCM functions.

But the BCM is not the module responsible for the TPMS system. It does not receive the TPMS radio frequency signals and it does not store the sensor ID numbers.

The PIDs for sensor IDs and pressures are housed and handled by the LGM also and not the BCM.

So does the BCM send some serial data message to the LGM to cause the LGM to enter a relearn mode?

Or does the BCM run some routine that catches serial data messages sent from the LGM in response to a change in tire pressure?

And what of the sensor IDs? Those are not routinely sent out on the serial data bus like pressures are.

Questions, questions.

Tomorrow I may record the serial data traffic while attempting a relearn on my Yukon. The relearn will no doubt fail to complete since my sensor batteries are now near 18 years old. But maybe I can catch enough to gain some insight into how this all works.
 
  • Like
Reactions: azswiss and budwich

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
Of course... But this was meant to be visually suggestive... because it would seem that the BCM might be capturing the Rapid Light Switch Activity as it's TPMS *Trigger* ...so monitoring whatever the BUS Activity is doing in that device and in between them... might prove interesting.
 

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
So I did indeed record some sessions and am evaluating the recorded data.

I will assume that GM uses essentially the same sort of programming for both the Tahoe/Yukon and the TrailBlazer/Envoy.

In anticipation of releasing air I first aired up all tires somewhat above what I would otherwise run at. I recorded this and in the data I can see that the frequency of pressure cahnge reports from the TPMS module, in the Yukon this is the PDM, varies. I see reports at pressure differences of one or two psi. My suspicion is that the sensor actually works in kPa and due to the conversion it is not a regular variance in psi. A guess. Doesn't really matter anyway.


My next recording is of activating the relearn mode. The serial data clearly shows that the BCM directs the TPMS module to enter the relearn mode by way of a serial data message. The TPMS module takes a couple of actions and reports back that it got the message from the BCM and is doing the neccesary tasks. Among these tasks is the flashing of the TPMS warning light in the IPC.

This is perhaps a clue to those who hear the horn beeps but don't get the flashing TPMS warning light in the IPC. The BCM can sound the horn itself but it takes the TPMS module to get the relearn going and flash the warning light on the dash. This could mean that the TPMS module did not get the serial data message directing it to enter relearn mode.

So I get the two horn chirps and begin releasing air from the front left. No response. I judge this is not working so I grab my U508 universal relearn tool and hold down the button while placing the tool against the sidewall near the valve stem. In about 5 seconds I get the horn chirp.

I proceeded around the vehicle briskly with the U508 tool as the 5 minute time clock is running. I get the remaining wheels done with the single chirp sounding pretty quickly. Turn the key to OFF.

Checked the left front and find I had released 8 psi without getting the horn chirp.

Looking at the recorded serial data I can confirm that the TPMS module was silent this whole time which was nearly a minute and a half of air release.

Granted, my batteries are from 2005 and the sensors are in a low power mode of operation but every one of them reported within 5 or 10 seconds with the U508 relearn tool. Maybe these relearn tools overide low power settings?

I can see in the serial data an exchange between the TPMS module and the BCM for each sensor that reports when prompted by the tool. There is no exchange of data to suggest that a sensors unique identity is passed to the BCM. Each repitition is only identified as the first, second, third, and fourth sensor received.

Cylce the key to RUN and observe the pressures in the DIC. All zero psi. Curious. Air up the front left that was deflated for the relearn attempt and that sensor reports in. One good.

Try the U508 tool on one of the others to see if it will awake and report,,,, nothing. After a while I get a second wheel to report. Two still AWOL.

Here it starts to get more interesting. I query the PIDs for the tire pressures and get the expected results, NOT and zeroes.

So the Module seems to know the actual pressure but is not sending those two to the cluster. Even when I request the pressures using class 2 communications messages I get 2 tires with pressure and 2 with zero psi. Very odd.

I am going now to dinner and a test drive to see if everyone comes on board.

20230317_145210.jpg
 

budwich

Member
Jun 16, 2013
2,027
kanata
have a good supper.... you might need it.

I am not sure that I understand the last part about your findings. You can do specific pid queries which show values..... but the info on the dic does not show correct info.... but are you monitoring the device for traffic during the dic "queries" to see what / any messaging going or are you just telling us about the visual results?

I am thinking "bus congestion" maybe. I have seen this type of thing in the past as I have gotten the warning. Pulled over to look at the display and gotten the ---. I can't remember if I turned off the truck or recycled the dic which then gave "valid values" and was good again. I attributed my issue to the use of the torque app causing issues either in the air itself or the comms between the dic and pcm / bcm (i don't know who would respond... lgm directly)?
 

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
So when I came out for the supper run all was working fine, not like the image I posted earlier.

Yes, I recorded ALL traffic on the bus during the exercizes.

As far as the DIC goes, the cluster doesn't request the data at all. The TPMS module broadcasts the data in response to a change in data, and perhaps after a set period of time I suppose.

Whenever I have seen the "---" display for a wheel I have beleived that comms with particular sensor had been lost,. likely due to my very old batteries.
 
  • Like
Reactions: Mooseman and mrrsm

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
As for delving further into the inner Mysteries of TPMS... it does NOT get any more unusual than THIS:

I just remembered... Back in Post# 2,146 over in the "What Came In The Mail Today?" Thread I had started to delve into the Hardware and Software of SDR (Software Defined Radio) in part; to get a better understanding of my Wife's 2013 Nissan Altima TPMS system and in short order, I discovered just how Dangerous the HACKRF SDR Radio Sets can become in the hands of the uninformed ...or in those of Professional Spooks and Spies..

This Hand Held Device makes it possible to perform everything from being able to Hack into the TPMS Systems of Parked Cards and Flatten ALLThe Tires and Disable such Vehicles, to Hacking into the GPS System in adjacent moving cars in order to re-direct Suspect Vehicles to False Rendezvous Points in the End Games of Law Enforcement Anti-Criminal Operations.

But for the present On Topic use... the more mundane ability of using these Things can be to decipher the SDR TPMS Codes and then re-program the Radio Device Sensors for other purposes.



THIS One ...is mine:

158464-f941fbc8772f394ee79126c163c2f163.jpg
158469-94767967a75e9e93b0bb8bd0abba8e27.jpg

hackrfnportapack2-jpg.102018


To Learn More...Straight from The Horse's Mouth. All of THIS Technology evolved out of the complex mind of Michael Ossmann. THIS is his First Lesson of MANY on How To Use HACKRF or similar SDR Gear:


..and another, less expensive approach:

 
Last edited:

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
I am thinking "bus congestion" maybe


I think not, mainly because I know how the data comes through. The TPMS module sends ONE message that contains all 5 sensor pressures (there is one space available for the spare). Also in that ONE message is a single byte that I have seen display "10" when a tire is below the threshold for setting the warning.

Here is such a message below. The highlighted portion is the header section and particulars of the message. The next 5 bytes after the highlighted portion are the tire pressures in psi represented in hexadecimal. Thus the first value, left front tire, "29" is 2*16+9 for a decimal value of 41 psi. The next two bytes for the right front and right rear tires are zero. And the next byte for the left rear is again hexadecimal 29 which we know is 41 psi. The "FF" is where the spare tire would be if I had such and I suppose there might be some programming required for that? Or did all TPMS equipped vehicles come "spare ready" for TPMS? The "00" after the "FF" was "10" when I actually had a tire in alarm condition, the pressure being too low. Why it is not "in alarm" while 'reporting' two wheels at zero psi is another mystery.

I suspect that the programming in the TPMS module may be 'sectioned off' such that a diagnostic PID may have access to the data but the routine that handles the transmission of such data to the cluster comes up slower??



Screenshot_20230317-192229_aGrep.jpg
 

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
One takeaway of my experience today I would think is this:

If you do NOT get the flashing TPMS warning in the cluster while attempting to initiate a relearn I would suspect there may be some communications issue with the TPMS module.

In the TrailBlazer/Envoy platform this is the LGM. I would try out at least one serial data based function of the LGM to confirm reliable communications. Like do the key fobs work every time?

Or maybe another function that does not rely on the keyfob radio signal, like maybe the lock/unlock from DDM.
 
  • Like
Reactions: budwich

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
Any way to use your Tech 2 in combination to *Ping* under any Special Tests?
 

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
Any way to use your Tech 2 in combination to *Ping* under any Special Tests?
A tech 2 can ping all modules or a selected module. The exact same ping can be done with an OBD2 adapter and a free serial terminal app.

"Pinging" ALL modules is as simple as sending the message "6C FE F1 20". The bluetooth OBD2 adapters require the three byte header to be set first, then send the message.

ATSH6CFEF1 sets the header.

ATH1 turns on display of the 3 byte header so when a module responds you can see the address of the sender.

20 sends the "ping".

Every module that is operational will respond "60".

Screenshot_20211122-140842_Serial Bluetooth Terminal~2_20230317205328858.jpg
 
Last edited:
  • Like
Reactions: mrrsm

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
Another possibility for owners of an OBD2 adapter is this: these adapter can be told to filter incoming messages and print only those from or to a given module.

Every module active on the bus sends a "node awake" message no less than every two seconds.

You can set the adapter to just show you traffic from the module in question.

So for the LGM, in a serial terminal app type in ATMT20. All traffic from that module will show onscreen.

AT denotes and instruction for the OBD2 adapter, much like the days of old working with the Hayes AT command set.

MT here means Monitor Transmit.
 
  • Like
Reactions: mrrsm and budwich

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
Thomas.... WHOA! You Scared The BeJesus Out of Me!
 
Last edited:

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
In another thread....



When diagnosing battery draws on trucks equipped with the automatic dual zone HVAC controls (RPO CJ2), technicians should keep in mind that the control head does not completely “go to sleep” until after 150-250 minutes, or up to 4-1/4 hours, from when the ignition key is turned OFF. This is a normal condition. In these cases, DO NOT replace the control head.

This makes me wonder....

Why would such a module be programmed to remain active for up to 4.5 hours when there is absolutely nothing it can do during this time? It's not like it could perform any duty like turning on the A/C or heat.

Just seems bizarre that the device would be programmed in this way.
 

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area

Attachments

  • hoganmuller_02a_0712.pdf
    465.6 KB · Views: 0
  • Like
Reactions: Redbeard

TJBaker57

Original poster
Member
Aug 16, 2015
2,897
Colorado
The overwhelming majority of modules in our GMT360/370 platform are powered at all times and are activated by bus wake-up messages. To further refine what modules are in what state the BCM broadcasts power moding messages. I have read that there are even fallback states to deal with certain faults within the wiring systems.

An example, the unlocked drivers door is opened and the DDM sees this via the door jamb switch or door handle switch and immediately awakens and broadcasts "88 FF A0 02" which is defined in SAE J2178-4 Table 51 as "Bus Wake-up".

This is immediately followed by "8A C7 A0 A1 22" also defined in SAE J2178-4 Table 34 as "Door Handle Switch Active" for the drivers door.

Within milliseconds the BCM, having received the DDM messages broadcasts a Power Moding Message. In my TrailBlazer this is "28 FF 40 06 03 00 0F".

There are a handful of variations of this Power Moding message the BCM will broadcast as the conditions of the vehicles operational status changes.

But none of this tells us anything about what could an HVAC module be doing for 4.5 hours after the vehicle has otherwise completley shut down.
 
  • Love
Reactions: mrrsm

mrrsm

Lifetime VIP Donor
Supporting Donor
Member
Oct 22, 2015
7,639
Tampa Bay Area
Perhaps this a "Ghost In The Machine" sort of moment in which the unintended consequences happen when "The Rubber" of the Total System's Physical Modular Hardware... "Meets The"... ethereal and esoteric "Road" of the Code ...Written so that these SUVs can sort of be 'sensibly aware' of the Human Beings that approach them...Key them Awake ...Get IN...and Finally... Drive these Amazing and Magnificent GMT360 Vehicles off into the Sunset.

Without US.... They would all end up just being Piles of Metal, Plastic, Leather, Glass and Fabric, Fuel and Oil ...resting quietly around here and there upon their Wheels. And perhaps for around Four and a *smidge* Hours or so... Wondering at a steady pace, "When we will come back to Drive them again?"
 
Last edited:

Forum Statistics

Threads
23,273
Posts
637,483
Members
18,472
Latest member
MissCrutcher

Members Online