99 Outback. AT oil temp flashing. Please Help!

[Nick6]

Please help!  I just bought a 99 Subaru Legacy Outback with the 2.5l H4 motor and automatic trans.  Car has 46k miles.  I used Seafoam through a vacuum line to clean the engine because I was told the car had been sitting for a while.  I put 1/3 of the can in at idle and then shut the car off to let the product soak in for 30 min. Upon starting the vehicle back up I noticed the AT oil temp flashing steadily.  I performed a 10 mile drive to clear the seafoam out as directed... and the AT oil temp was still flashing.  I let the car sit overnight and started it cold... Light is still flashing.  Trans fluid is very clean, however, when making tight turns it feels like the car is grabbing hard.  When the wheel is straight the car moves freely with very minimal gas given.  Now my check engine light is on and I’m getting a P400 code for EGR.  Any ideas?   

 

Thanks!

[3Pin]

Just my 2 cents, I am not a fan of the seafoam thing. I know others have had positive results in some cases, but I will clean the intake with some spray and that is about it.  Others can comment with their own experiences. On the at oil flash,  It is flashing with a pattern or a steady flash?  Was it doing it before the seafoam treatment?  Check to make sure all of the tires are the same size, brand and air pressure.  Check the trans fluid level and do a couple of drain and fills before you look at whether it is the duty c solenoid.  Good luck with the really low mile find as well.

[Nick6]

6 hours ago, 3Pin said:

Just my 2 cents, I am not a fan of the seafoam thing. I know others have had positive results in some cases, but I will clean the intake with some spray and that is about it.  Others can comment with their own experiences. On the at oil flash,  It is flashing with a pattern or a steady flash?  Was it doing it before the seafoam treatment?  Check to make sure all of the tires are the same size, brand and air pressure.  Check the trans fluid level and do a couple of drain and fills before you look at whether it is the duty c solenoid.  Good luck with the really low mile find as well.

The AT Oil Temp light is a steady flash.  It’s starts as soon as I start the car (even if the engine is cold) till I shut the car off.  The car didn’t do this until I used the seafoam treatment. Tires are all the same.   Same size, brand, and air pressure.  Trans fluid looks great... pink and full.  What is the duty C solenoid?

[GeneralDisorder]

The duty-c solenoid has likely failed. Check the resistance through the solenoid coil. 

And seafoam is a waste of time. Especially since sooner or later you will end up replacing the head gaskets on that short-cycled 25D and then you can clean the combustion chamber and piston tops by hand anyway. 

GD

[wtdash]

Maybe I missed it and GD is (very) Likely correct, but the flashing AT light tells you there is a code stored in the TCU (trans computer), which is separate from the ECU. SEARCH on here/online to find out how to retrieve the actual code...also called a 'handshake'.

Use the FWD fuse under the hood  - you read the Owner's Manual, right ?? - to determine if it's mechanical (clutch pack(s)) or eletronic (Duty C). If the TB/torque bind goes away w/the FWD fuse IN it's the clutch packs.....you can guess the other option. :-)

GL,

TD

 

p.s. you ran an Autocheck or Carfax to confirm those extremely low 46K miles?

 

 

[Mike104]

I expect with a 99 and the known issue of the intermittent speedometer the speedo/odometer has likely been changed

[GeneralDisorder]

He mentions torque bind and 99% of the time that's going to be a duty-c code. 

GD

[carfreak85]

9 hours ago, Mike104 said:

I expect with a 99 and the known issue of the intermittent speedometer the speedo/odometer has likely been changed

Was this a thing?  Were the '99 speedo/odos failure prone?

[Nick6]

The mileage is absolutely accurate.  What is harder to replace, the duty C solenoid or the clutch packs?

[idosubaru]

On 11/25/2018 at 8:36 AM, Nick6 said:

 and the AT oil temp was still flashing.  I let the car sit overnight and started it cold... Light is still flashing.  Trans fluid is very clean, however, when making tight turns it feels like the car is grabbing hard.  When the wheel is straight the car moves freely with very minimal gas given.  Now my check engine light is on and I’m getting a P400 code for EGR.  A

1. Repair the EGR valve code first - that's easy.  Replace with OEM, used, or remove and clean it and verify associated lines or it's operation.  There's a small in line quarter sized filter on the passengers side of the engine bay - replace that as well. 

2. AT light blinking - replace the Duty C solenoid.  You could test it just to make sure it's not a broken wire from rodents chewing it if that's possible depending where/how it was sitting. 

 

 

 

[idosubaru]

1 hour ago, Nick6 said:

The mileage is absolutely accurate.  What is harder to replace, the duty C solenoid or the clutch packs?

same. both require removing the rear extension housing of the trans.  it doesn't require removing the transmission so it's not an awful job but does require working under the vehicle, looking up, and is sizable in scope for a new person. 

[mikec03]

I had the dealership replace the duty c solenoid for $600 in my 95.  This gives the Op some idea as to the cost.

[wtdash]

If you check the FWD fuse and it's mechanical, I'd spend the $$ on 2-3 gallons of ATF (and I noted your ATF looks good):

Quote

the recommended (on most sites I frequent) # of Drain/Refill/Drive (thru all gears) cycles is 3. This gets 90% of the old fluid out of the pan AND the torque converter..... the Dex III-compatible is correct, per the OM.

.....and then go drive it in figure 8's in a parking lot - and not the interstate :-).  Sometimes it'll free it up...yes, it worked for me. Your car has obviously sat a lot w/those low miles, so may just need some new ATF and some drive-time. 

Also, I DO NOT recommend it being power or chemically flushed by a shop as it can cause issues w/the seals in an older trans...I lost Reverse...yes, yes, I did...and had to have it rebuilt. :-(

 

 

Edited November 26, 2018 by wtdash

[GeneralDisorder]

There would be no code if it just needed a flush. 

GD

[wtdash]

15 minutes ago, GeneralDisorder said:

There would be no code if it just needed a flush. 

GD

Gotcha...Duty-C isn't 'smart'...it just varies its amount of engagement on input from TCU, and reports back...If it's not reporting back =AT Temp light flash

Edited November 26, 2018 by wtdash

[Nick6]

22 hours ago, wtdash said:

Maybe I missed it and GD is (very) Likely correct, but the flashing AT light tells you there is a code stored in the TCU (trans computer), which is separate from the ECU. SEARCH on here/online to find out how to retrieve the actual code...also called a 'handshake'.

Use the FWD fuse under the hood  - you read the Owner's Manual, right ?? - to determine if it's mechanical (clutch pack(s)) or eletronic (Duty C). If the TB/torque bind goes away w/the FWD fuse IN it's the clutch packs.....you can guess the other option. :-)

GL,

TD

 

p.s. you ran an Autocheck or Carfax to confirm those extremely low 46K miles?

 

 

I checked the fuse box for the fwd fuse and didn’t see a spot for the fuse.  Is it labeled as something different?  Possibly located outside the fuse box?  I don’t have an owners manual so no, I haven’t read the owners manual.  I’ve looked online to try and retrieve a manual with no success.  Any additional info would be greatly appreciated.  Also, would a mechanical failure cause the AT oil temp light to flash?

 

Thank you!

[Nick6]

1 hour ago, GeneralDisorder said:

There would be no code if it just needed a flush. 

GD

 

6 hours ago, idosubaru said:

1. Repair the EGR valve code first - that's easy.  Replace with OEM, used, or remove and clean it and verify associated lines or it's operation.  There's a small in line quarter sized filter on the passengers side of the engine bay - replace that as well. 

2. AT light blinking - replace the Duty C solenoid.  You could test it just to make sure it's not a broken wire from rodents chewing it if that's possible depending where/how it was sitting. 

 

 

 

Thank you for the advice!  I’ve looked for the filter you’re talking about on the passenger side of the engine bay... but have had no success finding it.  Can you give me a bit more detail as to it’s location?  My EGR valve, when pressed in by hand, has no impact on how the car is running.  I assume when pressing on it, it should cause the engine to want to stall... is that correct?  Is that an indication that the valve in fact needs replacement?

Also, is there a good place to test the wiring from the duty c solenoid (under hood or under car)?  Is there a specific wire color associated with the solenoid?  I want to ensure I’m testing the solenoid and not another component.  Still new to Subaru so any help is greatly appreciated!

Thank you?

[wtdash]

OM: http://jdmfsm.info/Auto/Japan/Subaru/Legacy_Outback/1998/Owners Manual/

It's a '98 but '99 is very similar.

FWD fuse is under the hood by the passenger side strut tower.

 

[GeneralDisorder]

Pull the EGR valve off and check for blockages - if you find none then you most likely need to replace the Back Pressure Transducer. It's the plastic UFO looking thing above the EGR valve on a bracket. They fail on the regular. Dorman makes replacements for like $25

GD

Edited November 27, 2018 by GeneralDisorder

[Nick6]

2 minutes ago, GeneralDisorder said:

Pull the EGR valve off and check for blockages - if you find none then you most likely need to replace the Back Pressure Transducer. It's the plastic UFO looking thing above the EGR valve on a bracket. They fail on the regular. 

GD

Ok, will do.  

Thank you!

[Nick6]

17 hours ago, GeneralDisorder said:

Pull the EGR valve off and check for blockages - if you find none then you most likely need to replace the Back Pressure Transducer. It's the plastic UFO looking thing above the EGR valve on a bracket. They fail on the regular. 

GD

Ok, will do.  

Thank you!

[Nick6]

What are the ramifications of driving the car with a faulty Duty C solenoid?  I’ve probably  driven the car 70 miles since the AT Oil Temp light began flashing.

[idosubaru]

4 minutes ago, Nick6 said:

What are the ramifications of driving the car with a faulty Duty C solenoid?  I’ve probably  driven the car 70 miles since the AT Oil Temp light began flashing.

The drum/hub inside the rear transmission housing can shear off, that's the only failure I've seen. The binding would be felt by the entire driveline - transmission 4WD components, driveshafts, differentials, axles.  

You can disconnect the rear half of the driveshaft and just run it in FWD.  Either indefinitely or until you can get it fixed. 

Edited November 27, 2018 by idosubaru

[Nick6]

I installed a 20 amp fuse in the FWD drive slot under the hood near the passenger strut.  The binding I was getting before I installed the fuse is now gone.  Is this an indication that the clutch packs are bad, or the Duty C Solenoid is faulty.  And which is the more costly repair?

Thanks!

[GeneralDisorder]

What codes are you getting from the TCU?

GD