My '96 A4 coupe's transmission is misbehaving. I've got two leads based on my code reader and searching the forums - but wanted to see if anybody had any further wisdom or predictions while I wait to take her to the shop.

A couple of weeks ago she started dropping out of 3rd or 4th and into 2nd towards the end of my drive to work. (It's not a daily, just the occasional trip on a nice day). Doofus that I am, and still in the honeymoon phase after having it for less than a month, it took me a few trips to realize that it was doing it consistently. The SES light wasn't lit, and at low speed (< 30mph or so) it's fine. It'll frequently go higher at the start of a trip but after a few miles it drops to 2nd and stubbornly stays there. It's definitely starting in 1st and shifting up to 2nd (I can hear/feel the shift). Based on that symptom and searching the forums, the likely culprit seems like a worn 3/4 clutch or clutch pack, whatever it's called. Which apparently means a rebuild. Frowny face.

Last week I got myself a code reader because my CT emissions test was due today and I wanted to see if she stood any chance of passing. To my surprise, it claimed all the I/M monitors were ready - which I interpreted to mean that it would pass muster - and there were no codes set. But to my further (and less pleasant) surprise, the car didn't pass and the shop's reader came up with code P1810, "Transmission Fluid Pressure valve position switch circuit". The SES is now on and P1810 comes up on my reader too. (I'm wondering if I didn't pick up the code because I only checked it with the engine off - we have a 1 year old whose room is adjacent to the garage, and my Corvette time comes when she's asleep...and I'm not taking chances on waking her up). Googling around seems to indicate that the TFP is comparatively cheap and that a transmission shop could fix it (or reset a loose connector, whatever) pretty easily. But would that explain the lack of 3&4? Maybe I've got two faults on my hands. And why didn't I have an SES light until the emissions test was done, and why didn't I get the code in the first place?

What's most annoying is that I was planning to shut her down for the winter (garage/cover/overinflated tires/battery tender) in a couple weeks anyway and would have waited until spring to fix it when I've got a slightly fatter bank account again. But because of the crummy timing of the #@$*(@#%!! emissions test, I've got to get it done in 60 days. We have a reputable transmission shop nearby but it'll be a couple days before I can get her over there to see what they say. I'm wide open to any thoughts or advice in the meantime...

 

PM member Confab and ask him to look at this post. He will know. Dan

 

Thanks Dan, just sent him a message. I'll update the thread if I hear anything back and after she goes into the shop later this week.
John

 

Did you check your fluid level?

 

a transmission code will cause a fail on an emissions test?

Must be a CT thing because only thing in TX that will cause an emissions test fail is an actual emissions code or monitors not ready.

 

4l60e is electric shift. Transmission defauts to second only. The dtc p1810 needs to be looked at first. Excessive material in pan would indicate clutch failure. The electronic part is diagnosed mostly without any disassembly a bidirectional scanner or test box and a pressure gauge. Pan is removed to access most electronic parts..

 

I believe the fluid level is fine but I haven't verified that yet. I wanted to right away last weekend but got struck by the stuck-hood gremlin and couldn't get the driver's side to release (there's an "emergency release" made from a clothes hanger from the PO, but I hadn't had to use it previously and it doesn't seem like it's routed correctly to actually, you know, do anything). I bought some steel rod last night to make myself a helper, so I'll finally be able to get that done tonight. The garage that sold me the car claimed that they'd checked the fluid and that it was fine, and there have been no fluid drips from the car at all. If it was in there ~150 miles ago, I can't imagine how it got out. It's always possible that the mechanic conned me, but he was upfront with me about other issues (...including the balky hood) so I don't know why he'd bother. Either way, I'll know tonight.

@Kevova , if I understand you right the shop will (or should) be able to check out the TFP valve that's causing the DTC P1810 code remotely before taking anything apart, and then drop the pan if a) it needs to be replaced or b) the result is inconclusive and they need to check the pan for evidence of clutch failure? It'll be nice to compare that to what they tell me the plan is...

@rjacobs Best I can tell, they'll fail you here for any code regardless of how it may or may not impact your emissions (although to be fair, I imagine being stuck in 2nd all the time would indeed impact my emissions). The "thanks for trying" failure report doesn't even give you the specific code, just "manufacturer transmission code". So helpful. I've only lived in CT for about 6 months but so far I'm not a fan of anything vehicle-related...

 

I'm not familiar with this code, but IF it's one that takes a while to set after resetting, there may be a workaround in order to get it put away for the winter and deal with it in the spring.

Most states allow some number of "not ready" codes. Generally they allow more of them for the early OBD2 cars. In the places I've lived your 96 would be allowed two.

So you use your scanner to clear codes, then drive until you have all but two codes "ready". If one of the two unready codes is the bad one, then you just have to do a reset and drive that many miles/minutes to the inspection shop.

In your case since it already failed you have to worry whether the failed code went into a state database in which case they might not accept "not ready" for that retest. Most states don't have that capability but CT might.

 

Just to close the loop in case somebody has the same symptoms in the future: the transmission fluid pressure switch WAS the culprit. More specifically, the seals around where it mounts to the transmission were leaking, so the switches weren't getting activated properly and it was defaulting to 2nd. I had them replace the whole part just to be safe (since it was only ~$40), and she's all back to normal with a fresh shot of transmission fluid to boot. Relieved that it was the TFP and not something worse...