5EAT in 2wd problem...........

[Primotenente]

Great work plain OM!

Unfortunately I don't have a windows based notebook at hand anymore, so I can't record some data to verify his data, as I would have a 5EAT.

[cardoc]

Rom Raider does have the ability to read each wheel speed sensor independently and also the ABS/VDC front and rear. Maybe AWD should try it again with these parameters being recorded. Would save him a headache in jacking up the car, having someone hold the driveshaft still while turning the wheel(s). Then the wheel speed sensor readings could be compared to the front and rear output speeds.

It would also help in locating which side is being effected most.

[plain OM]

Originally Posted by cardoc

Rom Raider does have the ability to read each wheel speed sensor independently and also the ABS/VDC front and rear. . . .

I would really like to have that for my car, but doesn't it depend on the TCM (year, model etc)?

In my case, when I open Romraider Logger without connecting to the car, a long list of potential PIDs appears, including the four wheel speeds you mention, but when actually communicating with the TCM (or ECM), they do not appear, along with a lot of other potential but, unfortunately, absent readouts.

Back in the FreeSSM thread, (post #131 and 139), I compared the list of TCM readings on the Logger with the list of PIDs available according to the FSM for my car, and found that, with the then "experimental" definitions, I had all but one. The four wheel speed series do not appear in the list.

I don't see the four wheel speed signals listed in the FSM for the 5EAT either. Are they accessed through the TCM, or is the Logger capable of accessing the ABS control module as well?

Happy Holidays

[AWDPete]

Just to clarify, at 5950 to 6150 I did the following: applied parking brake, pushed accelerator pedal, released parking brake, launch!

My daughter took her laptop with her to Colorado for the week however I might be able to borrow one before then.

[plain OM]

Just to clarify, at 5950 to 6150 I did the following: applied parking brake, pushed accelerator pedal, released parking brake, launch!

Yes, that all seems to show at around point 81 in the last graph ("Expanded view . . .") I added. I say "seems" because I presume the pedal advance, brake release and launch were almost at the same time, at least that's what the data seems to show. There's no sign of the accelerator being held down for any length of time with the parking brake on and the transmission in gear. That would be evident from the Delta increasing well above the roughly 700 rpm base level along with an increase in solenoid pressure but zero wheel speed.

In the last graph, at around point 81, the accelerator is advanced, the solenoid target pressure starts to go up as does the Delta, and within a fraction of the same second the wheel speed starts to rise. As noted, that last graph covers only 7.5 seconds, so we're looking at a lot of change in a very short time.

The range 5960 to 6150 goes beyond that "launch" -- it includes the full cycle from "launch" through peaking out and then the decline to zero of wheel speed, and both the Delta and solenoid pressure returning to their base (idle) levels.

[cardoc]

I don't have a 5EAT available to connect to for verification. When I connect to the Outback or another Gen 2, I have a lot of options for data logging including the ABS signals. I used it to check for torque signals from the TCM and make sure the ABS/VDC wasn't causing the "kill" at 5500 rpm prior to finding the collapsing intake tube.

It seems to be a mechanical issue. If a long period of front wheel slip can be recorded and the data shows rear speed, its a gimme that something beyond the rear shaft is disconnected. And apparently its intermittent, (all wheels spin on the lift without load). Which goes back to checking pressures or dropping the pan for a check for clutch materials/metals.

[plain OM]

And apparently its intermittent, (all wheels spin on the lift without load).

That's right -- "load" can be the key factor. If a rear axle CV joint is broken internally, but the boot is intact or if there's stiff grease in the CV joint, the wheel could turn when not on the ground, but doesn't when down. In the latter case, neither the boot clamps on the axle shaft nor the grease will transfer enough torque to cause the wheel to spin.

Rom Raider does have the ability to read each wheel speed sensor independently and also the ABS/VDC front and rear.

When I connect to the Outback or another Gen 2, I have a lot of options for data logging including the ABS signals.

Is that with Romraider Logger or is it with the Romraider ECU-mod program running?
Can you post some screen shots with the ABS signals showing? I'd really like to see what's different in your setup and if perhaps I'm misusing the program somehow and therefore not seeing the 4 ABS wheel speed readouts.

[Petersubaru]

is there a reason why the rear cv axles haven't been tested/checked..

[AWDPete]

Originally Posted by Petersubaru

is there a reason why the rear cv axles haven't been tested/checked..

nothing other then available time - 32 hours of overtime last week

OK, not sure what to make of this, I jacked up the driver side and with the trans in park I could turn the rear wheel by hand. There was some drag but it's a viscous diff right? so I lower it down to the ground and lift the passenger side, when I go to spin the wheel I hear a clunk and I can't budge it? so I drop it down and lift the drivers side again - won't budge now either?

My assumption is in park the driveshaft won't spin, the floorjack was on a board on top of a foot of snow so I didn't crawl under it to see if the shaft was turning. Don't know what to think of this?

Merry Christmas everyone

[plain OM]

Originally Posted by rasterman

I might have to take another swing at getting my vagcom cable to work, just so I can try the same thing on my 5EAT and see how it compares.

Cable works great in FreeSSM but romraider has yet to recognize it.

Very informative thread!

That would be very(!) helpful here as well. We have no data from a 5-speed to compare to. For example, the turbine 1 and turbine 2 series (are both available, how do they compare, and what is the relationship the Turbine Rotation Speed figures?).

While the rear drive mechanical integrity question remains paramount, I have a feeling that the absence of the turbine 1 signal, and perhaps the absence of a rear vehicle speed signal (the stored trouble code), are affecting the way the AWD clutch is actually working. The "AWD Solenoid Target Pressure" might be what the TCM "would" command if there were no prior problems, but in fact, that target isn't being implemented in terms of the actual control of the clutch. We've seen something like this her before -- in the 4-speed, if the TCM detects a problem in the AWD Solenoid circuit, it will trigger a corresponding code. Inserting the AWD disabling fuse to put the car into FWD mode apparently doesn't work -- that part of the TCM function is disabled as long as there's a prior trouble code related to the AWD system.

If the cable works with FreeSSM it's very strange that it doesn't work with the Logger. Wasn't there a case earlier where the COM port had to be changed from 2 to 4 (or vice-versa)?