auto problem/ intermittent power light

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lucas
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Location: tacoma washington

auto problem/ intermittent power light

Post by lucas »

My wifes car has developed a strange problem that is beyond my skill

her car is a 1993 sport sedan automatic with 289,XXX miles on it.

Earlier this week she had notices the "Power" light would randomly come one while driving with a notice able rise in RPM and she says the car will drive differently. She said it only happened a few times while cruising on the Freeway.

I had her take it to a shop locally and they old subaru wizard said he couldn't find anything mechanically wrong with the tranny all the fluids checked fine.

When I got home from work I drove it around till it was warmed up and checked the trans for codes, all the power light did was blink repeatedly. I interpreted it as there were no stored faults.

Has anyone else experienced this problem or can maybe point me in a direction to work towards?

Thanks, Lucas
1993 legacy ss "Shela"
wtdash
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Re: auto problem/ intermittent power light

Post by wtdash »

Hi
Did you do both code 'handshakes' to check for Active and Stored codes?
https://www.surrealmirage.com/subaru/trans.html
Does it ever flash 16 times when first started up?

When was the trans last serviced? 289K is a lot of miles, so I'd be thinking the trans could be getting tired. An actual trans shop may be able to diagnose it better....but that's not (usually) free so you're asking here first obviously.

Based on the symptoms I'd lean toward a torque converter issue, but don't know how to diagnose that. :-(
GL,
Td
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lucas
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Location: tacoma washington

Re: auto problem/ intermittent power light

Post by lucas »

I only did the current check. I last serviced it about 20k ago but it may be time again given the age. Also the mechanic was leaning towards and electrical or solenoid issue. Ill do the other check today and report back my findings
1993 legacy ss "Shela"
Legacy777
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Re: auto problem/ intermittent power light

Post by Legacy777 »

Yeah, I'd check for stored codes and would agree it's likely electrical or solenoid based because the power light came on.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
lucas
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Joined: Tue Nov 27, 2007 2:43 am
Location: tacoma washington

Re: auto problem/ intermittent power light

Post by lucas »

well no good news because both checks now have yielded the same result, a continuous quick flashing light....
Maybe the TCU is going bad or I have a loose connector?
1993 legacy ss "Shela"
Legacy777
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Re: auto problem/ intermittent power light

Post by Legacy777 »

Check for loose connectors at the TCU and the two big squarish trans connectors in the engine bay.

The other thing I'd suggest trying is checking the resistance of the solenoids in the transmission.

https://main.experiencetherave.com/suba ... _diag1.jpg
https://main.experiencetherave.com/suba ... _diag2.jpg
https://main.experiencetherave.com/suba ... _diag1.jpg
https://main.experiencetherave.com/suba ... _diag2.jpg
https://main.experiencetherave.com/suba ... _diag1.jpg
https://main.experiencetherave.com/suba ... _diag2.jpg


https://main.experiencetherave.com/suba ... _diag1.jpg
https://main.experiencetherave.com/suba ... _diag2.jpg
https://main.experiencetherave.com/suba ... _diag1.jpg
https://main.experiencetherave.com/suba ... _diag2.jpg
https://main.experiencetherave.com/suba ... _diag1.jpg
https://main.experiencetherave.com/suba ... _diag2.jpg

Lastly, check that there is a ground wire from the transmission to the chassis. I ran across this on a friend's Legacy here in Houston. It was throwing a code for one of the solenoids. The resistance and everything checked out. However the small wire between transmission and chassis (firewall area) had broken. The caused a difference in reference ground at the TCU that put the sensors out of "spec". I wired in a new ground wire and the light didn't come back on.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
lucas
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Location: tacoma washington

Re: auto problem/ intermittent power light

Post by lucas »

christ thats a lot to check ill start with the ground and work back from there.
1993 legacy ss "Shela"
Legacy777
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Re: auto problem/ intermittent power light

Post by Legacy777 »

Ok, let us know what you find out.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
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