01M with P0748 - need a TDI mechanic or will any AT shop do?

Hi all-

Pretty sure I know what's wrong with my 01M trans, but my usual mechanic is out of town and had a few weeks' wait when I last talked to them before they went on vacation. My local general mechanic (I refer to him as urgent care) referred me to a local AT shop. So my question is ... for something like the alleged solenoid issue I have, do I need a TDI shop, or will a reputable transmission shop do?

If you want to hear more about my troubles, read on: shifts from park to 3rd only. I can shift in and move the vehicle to 1st, 2nd, and 3rd manually. No 4th (it's probably there but the car won't shift into it). Initially no CEL but when I turned it on this morning after letting it sit overnight, it produced P0748 ("17132 Pressure Control Solenoid Electrical" according to Bentley VW DTC Table).

Hard to say, the 01M is bit of a special beast, and finding someone good to work on them is a little tricky. The last time I had one rebuilt, the guy I went to subbed it out but we had a LOT of trouble with bad input seal installations, so even if I knew the name I'd be leery about suggesting them. There is "Import Performance Transmissions", who is in NJ; I've never used them, but their name does pop up from time to time on the boards.

If you're in a time crunch, you could try the guy I PM'd you the information on last summer, he might be able to help you out...

The 01M's are notorious for self-destructing at about 60k miles. Yours may be at the end of it's life. Be prepared.

Sadly a lot of transmission shops just want to rebuild the whole thing no matter what... and with that transmission you'll be entering into a long lasting relationship with that shop, as you'll have it back there repeatedly.

No reason they cannot properly diagnose and repair the problem. This is not anything a transmission shop should even be needed for, and to be real truthful I am not sure why said shops even exist. A good general repair shop should be able to diagnose and repair the unit if necessary, or replace it altogether. We do transmission control side repairs here every day... I just replaced a lead plate (a bus bar with all the electrical circuits) on a Ford 6R80 transmission this morning. Doing a ChryCo 6sp rand-o-fail slushbox on the other side of the shop.

The 01M's control bits are fairly simple, and not any different really than any other electronic controlled autobox (which today is ALL of them). In fact it is probably a bit simpler than a lot of other ones. So long as its hard parts and internals are OK, the control bits like the solenoids and harness, and at worst the valve body, are simple parts change items. It isn't any different than diagnosing a failed electrical part on the engine controls, or HVAC controls, or suspension, etc.

Rob Mayercik said:

If you're in a time crunch, you could try the guy I PM'd you the information on last summer, he might be able to help you out...

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My general mechanic was recommending a trans shop which is why I was wondering if a general shop would do. I've been making the trek to see Mike at M&M in Montague and he's been spectacular but he is on vacation for another week and, when I checked in with him before going away, was backed up with work.

MarsBar said:

The 01M's are notorious for self-destructing at about 60k miles. Yours may be at the end of it's life. Be prepared.

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Well, I'm 900mi short of 300k. Guess I have a better-than-average one. And yeah, I've been preparing for this since I found out they were a weak point (which was AFTER I purchased the vehicle, sadly).

oilhammer said:

A good general repair shop should be able to diagnose and repair the unit if necessary, or replace it altogether.

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I was hoping to hear from you Your experience with 01M has given me hope ever since I found out I had one. Don't stop believin', right? Also, I agree, it should just be a parts swap. My general mechanic didn't see it that way, but it looks like I'm going to hold out for my TDI specialist to get some space in his schedule. He is over 80mi away, so that won't help me if I'm going to have ongoing issues, but I'm there every 90 days or so for a rotating combination of engine oil changes and fuel filter/trans flush anyway. Everything else in the trans is as fine as one can expect it to be for its age, and I can shift through all of the gears I can access "manually" - it just won't shift by itself and throws the solenoid code. edit: I was in St Louis two weeks ago and now I'm sad I flew instead of making the drive out. As long as I get through this in once piece, I might be heading your way at some point later this year.

If you got 300K out of one 01M, you doing pretty darn good. my first one died at 68K, the second one went about 180K with dealer fluid changes every 25-30K. I had Mike from M&M send that one out for rebuild (the saga I mentioned above, he was NOT happy about having to pull my trans 3-4 times because of that rebuilder). That one's about 120K or so in, is running great. Royal Purple ATF seems to be agreeing with it.

I wonder if maybe you just have a sensor issue - other than the code, what you have sure sounds similar to what I had when my G68 sensor died over the winter. I lost overdrive and it started being real reluctant to shift (having to get up around 3500-4000rpm to shift. Might be worth hunting down CoolAirVW's 01M threads (there's 5), and maybe reaching out to him via PM as well. Once the sensor was swapped out, back to normal.

Downside to the G68 is that it's under the trans mount bracket, so you have to half-uninstall the trans to get at the thing (really don't know what VW was thinking on that one).

Might be time to read through CoolAirVW's 01M threads, he knows these boxes extremely well.

I hate threads like this, because the OP clearly needs a better place to have the vehicle serviced. I have no idea what anyone would shy away from that car's transmission problem. That is just dumb. It is so simple. This is why so many "transmission shops" end up being general diagnostic shops, because they end up having to deal with all the often non-transmission related stuff that others that are too stupid or too lazy to deal with. Sad state for the industry as a whole if you ask me. I just do not comprehend how ANY competent shop could function without some level of being able to diagnose and repair electronic controlled automatic transmissions, since 95% of everything on the road is so equipped.

You needn't be a "rebuilder" to deal with this. Why so many people jump straight to that is beyond me. Yes, the 01M is a known turd, but still, you really would be doing a disservice to yank the thing out, rebuild its mechanicals, put it back in, only to find it is doing the exact same thing because the REAL problem was corrosion in the connector for all the shift solenoids.

From the limited info the OP has given, sounds to me like there is a fault with the ATF pressure control solenoid, and the TCM places the unit into limp mode, as it would with most faults (normal operation). Could be the solenoid, the harness to the solenoid, the connector, or in some cases the valve body but that would be an extreme case and not likely to happen suddenly.

This is no different from a basic functional layout than the method the ECU uses to control the turbocharger. If you had no boost, and the engine went into limp mode, you would not send the car to a "charge air specialist", would you? No. You would also not IMMEDIATELY remove the turbocharger and replace it either. (although from some posts here you'd think otherwise ). No, you would diagnose the problem. Check the N75 solenoid (no basic electrical difference than the N93 pressure control solenoid in the transmission).

Sorry, just pissed off at such a simple problem and nobody closer to the OP to take it on.

That's why I related my G68 incident and mentioned the idea of reading up on CoolAirVW's 01M threads - the symptoms she reports seemed similar to what I had when that sensor failed, except for that code (I got a G68 code, as opposed to the code she is getting). It did seem like this could one of those "little thing causes BIG problem" scenarios.

The OP said her regular shop (a well-known "guru" on this board) was on vacation/backlogged right now and was looking for alternatives. I did suggest that if she was in a time crunch that she could reach out to the general mechanic I use (and trust), someone I PM'ed her info on last summer who is very close to me (and, based on what I learned during the PM exchange, fairly close to her too) when she was looking for someone at that time.

Rob Mayercik said:

If you got 300K out of one 01M, you doing pretty darn good.

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I think I got a good one. I acknowledge I'm probably on borrowed time, but I'm going to claim every damn second of it.

Rob Mayercik said:

I wonder if maybe you just have a sensor issue

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The other possibility (besides the pressure control/shift solenoids) I considered could have been the speed sensor, which, according to a quick Google, is the G68. So yeah, you and I are thinking along the same lines. I thought that because I usually slide into fourth/OD at exactly 40mph, and, when that didn't happen, I knew something was wrong. Also, I was in third gear when I shifted out of park instead of the normal first. So, third only, unless I "manually" shift to first, second, and reverse. The thing that made me leaning toward the solenoids was the error code.

Rob Mayercik said:

Might be time to read through CoolAirVW's 01M threads, he knows these boxes extremely well.

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As soon as I first heard the legends of the 01M, I sought out every piece of information about them I could find here (which is why I recognized oilhammer right away ), including reading every post I could unearth with a combination of "coolairvw" and "01m" search string.

oilhammer said:

I hate threads like this, because the OP clearly needs a better place to have the vehicle serviced.

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In defense of the only mechanic (NOT m&m Mike) I've talked to so far, he doesn't like to mess with any auto trans, not just specifically mine. I'm sure m&m Mike will have no problem with it when I tell him about it! My timing is just terrible.

oilhammer said:

I hate threads like this, because the OP clearly needs a better place to have the vehicle serviced.Sorry, just pissed off at such a simple problem and nobody closer to the OP to take it on.

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I'm sorry. Yeah, it's frustrating. With the decline from my general mechanic (who I rang first only because I knew Mike was away), I'm going to get in touch with Mike on Monday and see what he thinks I should do. I will update...

Rob Mayercik said:

The last time I had one rebuilt, the guy I went to subbed it out but we had a LOT of trouble with bad input seal installations

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This is why I'm willing to wait for Mike

Rob Mayercik said:

If you're in a time crunch, you could try the guy I PM'd you the information on last summer, he might be able to help you out...

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IF Mike quotes me more than three weeks' wait, I'll be giving your guy a call. I hate to stray from someone who has taken such damn good care of me, but it's (courier) business, not personal.

suchshutterfly said:

This is why I'm willing to wait for Mike

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Funny story - it was Mike who had my car when my transmission last died - I'd dropped it off with him (for something entirely not transmission-related), and he went out to pull it into the shop one day and none of the gears engaged (yes, it went from driving to not driving that fast). He took the trans to the place who he usually used for such things, and it took something like 3 tries before he got it back with an input seal that wouldn't self-destruct within a day or two and dump all the ATF on the ground.

I don't really blame Mike for the trans rebuild problems, it was the "parts supplier". I'm fairly certain he found transmission rebuilder to use soon afterwards.

suchshutterfly said:

IF Mike quotes me more than three weeks' wait, I'll be giving your guy a call. I hate to stray from someone who has taken such damn good care of me, but it's (courier) business, not personal.

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Mike does great work, and I understand being loyal to a good mechanic - I used Mike myself briefly and liked him a lot, but once he moved to Montague it became very difficult to coordinate with family members to get the car up to him or retrieve it (as he's about an hour and a half drive from me, in a direction completely different from my commute or that of the people I'd have to rely on to get to/from him). If he were closer, I might still be using him myself - he's definitely top-notch.

Good luck.

MarsBar said:

The 01M's are notorious for self-destructing at about 60k miles. Yours may be at the end of it's life. Be prepared.

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Hogwash.

Ah, there you are, Rich - was wondering when this thread would catch your attention.

CoolAirVw said:

Hogwash.

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yup, mine did 633k before I swapped it with a 5 speed... quite a few sensors, fluid changes, filter changes, two solenoids... etc
final straw was no reverse.

The biggest problem with these is no one wants to do the transmission service... eventually quite a few get swapped.

Rob Mayercik said:

Funny story - it was Mike who had my car when my transmission last died

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I have actually heard this story before! From the man himself ugh, what a nightmare.

Rob Mayercik said:

I used Mike myself briefly and liked him a lot, but once he moved to Montague it became very difficult to coordinate with family members to get the car up to him or retrieve it

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He's two and change hours and 80mi from me (the back way, 611 to Columbia and then onto 94 or something like that). I know I can call AAA and have them deliver the car to him (due to the nature of my work, I have their Premiere package which includes 5 tows under 100mi and 2 tows under 200mi). ... Not quite sure how I'm going to get it back yet. Might have AAA bring it home, too.

CoolAirVw said:

Hogwash.

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My 01M post is now complete, CoolAirVw is here! But, for real, I've been 01M fan girling for the last six months and I've dedicated countless hours absorbing your (and oilhammer's) wisdom. I have faith - so much that, should my 01M ever give up on me, I might put another 01M back in out of spite

alphaseinor said:

yup, mine did 633k before I swapped it with a 5 speed...

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THAT'S WHAT I LIKE TO SEE. My overall mileage goal is 500,000, so, if I hit that with the original 01M I'll be pleased as punch. It appears that my current 01M was reasonably well cared for at least 2/3 of its life. I let it go a little long without a trans service (just over 80,000mi) just because I didn't know any better, but that won't happen again.

alphaseinor said:

The biggest problem with these is no one wants to do the transmission service

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Or they're like me and they don't know any better and/or have well-meaning-but-wrong people around them who swear a trans service will kill your AT.

Guys, it has a filter. Calm down.

This has all been an awesome journey and I'd be a liar if I said I didn't spend most nights this week looking for a second ALH to bring home. The obvious answer to my problems is to have two, so, when one isn't driveable, I have one to fall back on. Makes sense, right?

suchshutterfly said:

I have actually heard this story before! From the man himself ugh, what a nightmare.

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Yeah, it wasn't fun for me or him.

suchshutterfly said:

THAT'S WHAT I LIKE TO SEE. My overall mileage goal is 500,000, so, if I hit that with the original 01M I'll be pleased as punch. It appears that my current 01M was reasonably well cared for at least 2/3 of its life. I let it go a little long without a trans service (just over 80,000mi) just because I didn't know any better, but that won't happen again.
Or they're like me and they don't know any better and/or have well-meaning-but-wrong people around them who swear a trans service will kill your AT.
Guys, it has a filter. Calm down.

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Success rates do seem to vary - my original one only went 68K and pulverized its reverse gear. At the time, the car was 100% dealer-serviced, and since the maintenance schedule in the book doesn't mention transmission, they never did it. (and I didn't think to ask explicitly for it)
The replacement (reman) got fluid/filter services every 12months/25Kmiles at the dealer (I started specifically requesting it), got about 180K out of it.
When that one refused to engage any drive gear for Mike, it got rebuilt (the aforementioned nightmare). First fill with Amsoil, after that Royal Purple and so far it's holding up really good.

suchshutterfly said:

This has all been an awesome journey and I'd be a liar if I said I didn't spend most nights this week looking for a second ALH to bring home. The obvious answer to my problems is to have two, so, when one isn't driveable, I have one to fall back on. Makes sense, right?

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Hey, if you got the space for it and can afford the cost, why not? Get another one while there's good ones still around to get, it's always good to have a Plan B on standby. (or, keep one stock for work and mod one for fun!)

Rob Mayercik said:

Success rates do seem to vary - my original one only went 68K and pulverized its reverse gear. *snip* The replacement (reman) got fluid/filter services every 12months/25Kmiles at the dealer (I started specifically requesting it), got about 180K out of it.

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I have to admit - I'd be a little upset if mine gave up the ghost after only 68000mi. This also makes me realize how incredibly lucky I must be. Also, mine must have been remanufactured at some point, because it was dealer serviced for 7/8ths of its life. If the maintenance schedule doesn't mention the trans, mine wasn't touched either ... and the fluid wasn't even low when they drained it at M&M 80000mi into my ownership.

Rob Mayercik said:

Hey, if you got the space for it and can afford the cost, why not?

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I can make the space, it'll just require some creative parking and a little extra nagging to have a non-operable Neon removed from the property

Rob Mayercik said:

Get another one while there's good ones still around to get, it's always good to have a Plan B on standby. (or, keep one stock for work and mod one for fun!)

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This region is FLUSH with ALH TDIs right now. I use an aggregator to search every craigslist in the lower 48, and there aren't a ton of quality specimens outside of the northeast. ... not reasonably priced, ready-to-drive vehicles, anyway.

Rob Mayercik said:

or, keep one stock for work and mod one for fun!

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A gentleman in Washington NJ made me a hell of an offer on a TDI, but I'm hesitant because it has a crazy tune and performance mods and I A. really don't need that much car, and B. If something expensive broke, I might not be able to foot the full cost of the repair right away, and that's no way to live.

But I can justify a second ALH, in decent condition, mostly stock, under 230000mi. Totally reasonable

suchshutterfly said:

I have to admit - I'd be a little upset if mine gave up the ghost after only 68000mi. This also makes me realize how incredibly lucky I must be. Also, mine must have been remanufactured at some point, because it was dealer serviced for 7/8ths of its life. If the maintenance schedule doesn't mention the trans, mine wasn't touched either ... and the fluid wasn't even low when they drained it at M&M 80000mi into my ownership.

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I was rather annoyed when I found out I needed a transmission (in my experience, if you can't get at least 100K out of it, something's clearly wrong with either design or implementation). It got to angry when VW essentially told me that "you're beyond the 60K powertrain warranty, piss off".

Never mind that I was only a couple thousand outside warranty (mileage only, not even close on time), and that other than one set of tires they'd done all the maintenance on the car since I'd bought it. VWOA had no interest whatsoever in making even a token gesture for the sake of goodwill - heck, there was some sort of TSB on the brake light switch, and even though I missed the mileage cutoff by less than 50 miles, they wouldn't budge on that either - I had to pay for the switch.

Oh yeah, and this was after both the dealer salesman and VWOA lied to me for two months about where my car was - that it was in port waiting for "inspection", when it was really on the boat up from Mexico. When I found out and called them on it, they flatbedded down an equivalent car to the one I ordered from Boston, though because it had Monsoon and the one I "ordered" didn't, I had to pay for the Monsoon option (though in retrospect, I don't regret ending up with the Monsoon anyway).

When the service writer informed me that I could only get a remanufactured transmission (at $5K installed) to replace it because VW policy was that once a vehicle was titled, a new one was not allowed (and besides, a "new" one would have been $10K just for the part), I actually pitched a fit in the service department, asking whether the thing's internals were made of gold for that price.

A couple hours later the service manager called me at work and said he'd knock 10% off the total cost, and I decided it was the best offer I was likely to get. Probably figured if he didn't do something I'd come back and make another scene in the middle of the service department (which happened to be within earshot of the sales area).

To be fair, though, the service department was (IMHO) one of the better ones - they seemed to know how to work on the TDIs, and even recommended changing the water pump at the first timing belt before I could ask for that. Before I went to Mike, they'd done nearly all the maintenance on it except tires and wiper blades and he never mentioned seeing signs of them having "tooefed" anything.

Rob Mayercik said:

I was rather annoyed when I found out I needed a transmission (in my experience, if you can't get at least 100K out of it, something's clearly wrong with either design or implementation). It got to angry when VW essentially told me that "you're beyond the 60K powertrain warranty, piss off"......................................

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Pretty common in the car industry. Most manufacturers have make a stinker or 2.

Rob Mayercik said:

When the service writer informed me that I could only get a remanufactured transmission (at $5K installed) to replace it because VW policy was that once a vehicle was titled, a new one was not allowed

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WOW ... I probably would have cut my losses and left the title with them at that point. There, now it's their problem. But you still have it!

Rob Mayercik said:

Probably figured if he didn't do something I'd come back and make another scene in the middle of the service department (which happened to be within earshot of the sales area).

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With this description, you have confirmed my suspicions about which dealer it was

Rob Mayercik said:

To be fair, though, the service department was (IMHO) one of the better ones - they seemed to know how to work on the TDIs, and even recommended changing the water pump at the first timing belt before I could ask for that. Before I went to Mike, they'd done nearly all the maintenance on it except tires and wiper blades and he never mentioned seeing signs of them having "tooefed" anything.

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Well, thank heaven for small favors. If I am right about which dealer it is, they broke my rear wiper at my one and only oil change there. I was very upset, because I had been pleased that it was still functional. When I contacted them, they wanted me to come back in before they would make any promises about being able to fix it. That just wasn't good enough of an answer.

You can PM me if you want to know the dealer in question, I think we've derailed your thread long enough with this...

Rob Mayercik said:

You can PM me if you want to know the dealer in question, I think we've derailed your thread long enough with this...

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Haha, no, it's ok To update: I heard from Mike promptly after his return from vacation. My Golf rode a rollback all the way to Montague yesterday afternoon. Just waiting to see what the good word is...

Why oh why are folks afraid to post bad dealers by name????

BobnOH said:

Why oh why are folks afraid to post bad dealers by name????

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I don't think it's fear. Not talking $h!t is generally a sign of good manners, and most people here already know to STAY AWAY FROM DEALERS, so it's not like a disservice is being done by being vague. All dealers are suboptimal, avoid if possible.

suchshutterfly said:

I don't think it's fear. Not talking $h!t is generally a sign of good manners, and most people here already know to STAY AWAY FROM DEALERS, so it's not like a disservice is being done by being vague. All dealers are suboptimal, avoid if possible.

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^this.

Besides, since the events in question were something like 13 or more years ago, I saw no reason to name the dealer publicly (especially since, for all I know, the people involved could easily have been gone for several years by this point, I've not been back to them for anything in at least 5 years).


Hope Mike finds you an easy and (relatively) inexpensive fix.

I suppose I should post the link to 01m solenoid diagnosis here and to my youtube video on solenoid diagnosis and replacement (different solenoid trouble code though)

http://forums.tdiclub.com/showthread.php?t=334614

https://youtu.be/NJpWGIbdgzQ

So, was Mike able to fix this thing?

Rob Mayercik said:

So, was Mike able to fix this thing?

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He’s waiting on the solenoid to come in!

Quote:
Originally Posted by suchshutterfly
I don't think it's fear. Not talking $h!t is generally a sign of good manners, and most people here already know to STAY AWAY FROM DEALERS, so it's not like a disservice is being done by being vague. All dealers are suboptimal, avoid if possible.

Rob Mayercik said:

^this.

Besides, since the events in question were something like 13 or more years ago, I saw no reason to name the dealer publicly (especially since, for all I know, the people involved could easily have been gone for several years by this point, I've not been back to them for anything in at least 5 years).


Hope Mike finds you an easy and (relatively) inexpensive fix.

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It is a disservice, there are good dealers and there are bad dealers.

Bob, I've not been to the dealer I had issues with in over a decade, so I have no recent experience with them. I see no reason to name them publicly with only information that old.

SuchShutterfly, good to hear - hope replacing that solves all the problems.