Electrical/Transmission Troubleshooting - Good shop in the Bay?
#1
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Join Date: Jul 2016
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Car Info: '06 Subaru Forester STI
Electrical/Transmission Troubleshooting - Good shop in the Bay?
Hey guys,
My Forester has been throwing a P0741 (torque converter) error lately when I'm on the highway and I'm looking for a shop that can accurately diagnose the problem. It could be the transmission harness, connector, a bad ground, bad TCM/ECM, bad torque converter solenoid, etc. Who knows.
I've taken it to a couple shops around home and they don't seem to know how to diagnose it - even though the service manuals lists out step by step a number of things to check, with many of them being electrical and requiring some knowledge of the components, connectors, and a multimeter. The two shops I went to, after seemingly fumbling around, told me I need a new transmission - which might be true, but they couldn't clearly tell me how they came to this determination (and they didn't remove the oil pan - how did you check the lock-up solenoid?).
Thus far, I have not been able to find anyone who can do this - besides myself but I can't get under my car as I park in a shared garage! I was thinking of going to Walnut Creek Subaru, as they seem to have good ratings, but I'd prefer to not go to a dealer.
Any guidance would be appreciated. I live in South San Francisco - don't mind traveling a bit if needed.
My Forester has been throwing a P0741 (torque converter) error lately when I'm on the highway and I'm looking for a shop that can accurately diagnose the problem. It could be the transmission harness, connector, a bad ground, bad TCM/ECM, bad torque converter solenoid, etc. Who knows.
I've taken it to a couple shops around home and they don't seem to know how to diagnose it - even though the service manuals lists out step by step a number of things to check, with many of them being electrical and requiring some knowledge of the components, connectors, and a multimeter. The two shops I went to, after seemingly fumbling around, told me I need a new transmission - which might be true, but they couldn't clearly tell me how they came to this determination (and they didn't remove the oil pan - how did you check the lock-up solenoid?).
Thus far, I have not been able to find anyone who can do this - besides myself but I can't get under my car as I park in a shared garage! I was thinking of going to Walnut Creek Subaru, as they seem to have good ratings, but I'd prefer to not go to a dealer.
Any guidance would be appreciated. I live in South San Francisco - don't mind traveling a bit if needed.
#3
If in doubt, FLAT OUT
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+1 for RBMS. There are a bunch of solenoids (9 or 10) on there and they do go bad with age and I'd say that's the most likely culprit. A good shop like RBMS will be able to find out if that's it and which one.
#5
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Thanks guys - much appreciated. Will give them a call - anybody know what I should expect for $$$ for troubleshooting like this? For a knowledgeable mechanic, shouldn't take more than an hour.
#6
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I called RBMS....they said they could take it for a "test drive" but didn't really have the equipment to test for problems like this. ???
#7
If in doubt, FLAT OUT
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4EAT? I've never taken an auto to him, but I would have expected them to be able to handle it. I took my former GF 4EAT to Garage 1 in SJ and they fixed it. Adam @ AA maybe then?
#8
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#9
If in doubt, FLAT OUT
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My GF had 250K before it started. Sorry to hear it. It is actually a good auto, but the solenoids go. That does seem early though. Give Adam a call and see what he says. I know a transmission guy, but again, he's in Santa Clara.
#10
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I'm really hoping it's not a solenoid as I don't believe they sell the individual solenoids - you have to buy the whole valve body which can cost as much as a used transmission! If I have to do that, I might either buy a used transmission or think about a 6MT swap...
#12
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But my RPMs seem to be fine??? At 65 mph, I'm right around 3,000 RPMs (a little below), which seem to be where it's supposed to be. When I hit the gas hard at that speed, the RPMs do jump a little bit, so that might indicate the torque converter is not locked? I've checked the trans fluid - it doesn't smell like it's burned - still looks new (I just flushed it last month).
#14
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Yeah, me too. I really have doubts it's the transmission.
#15
If in doubt, FLAT OUT
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With mine, it would whine or clunk when you put it in reverse and throw a light. Mann couldn't find it but Garage One in Almaden was able to figure out which solenoid and fix it, but it took them 2 days. Probably not the fluid IMO. PM'ed about another shop in Santa Clara.
Last edited by 04GG; 07-19-2016 at 09:41 AM.