My car has the issue where it goes into limp mode due to code 1776 (L/R solenoid switch valve latched in closed/open position)…but only after warming up, driving for 20 mins or so. I’m very curious why it doesn’t stick when its cold…never? Is it the valve/bore that has deteriorated OR the fluid (temp, cleanliness, chemical breakdown) that has occurred?
It would really be helpful if you told us what car you’re talking about.
I used to have a 2002 Saturn w/ automatic transmission. Was stuck in first gear. I replaced the valve body and it fixed the problem. Was about a 3 hour job.
Thx for such quick responses. Actually I intentionally didn’t mention the car brand because my goal is to figure out why a solenoid switch valve would stick only when warm and never when cold. A general question for any car transmission. Not really looking for labour cost or time to repair, or solution. Just very curious if it’s a worn or deteriorated valve for body or if it’s the fluid that is contaminated or chemically broke down or what that would cause it to stick only when warm.
then you can sit there and wait.
automatic transmission designs and control systems have diverged so greatly that we can’t tell you why your car is exhibiting certain symptoms unless you tell us what vehicle you’re asking about. If you think intentionally withholding that information is going to help you, then I wish you good luck.
Yes, I am waiting. I have patience, so I’ll be all right.
Maybe you can’t answer a theoretical question, but it doesn’t mean others can’t.
Yes.
Some transmission solenoids/valves are replaceable without tearing into the transmission very much and I would do some internet research and try replacing the solenoid if that’s indicated. You could try a fluid flush and some Lucas transmission fixer as a low risk first step.
Both conditions you described do happen. The fluid’s lubricity can deteriorate with age but many cars go 100K+ without any attention. Metal and the fluid expands when hot so their interaction can change. A valve could get sticky with old fluid or general crud.
It is helpful to give basic information like the car year, brand, model and MILEAGE.
If you have high mileage like 200,000 miles. Then I would recommend getting the transmission rebuilt.
He is not asking a question about his car, he has a theoretical question about valve bodies in general. This happens all the time here. I have had similar problems with solenoids on machinery, when they got hot they might either slow down or stop working. Sometimes it wasnt even hot, they simply had to be discharged and then start working again. Try shutting off the car and restarting t see if it has a reset affect. That might give you a clue.
I will wait for the OP to speak for himself.
He did speak and that was what he said, go back and read it.
the reason why I asked for the make and model of car is because it could be neither of those things. Since you wouldn’t do it, I’ll state that you have a Chrysler vehicle with an “Ultradrive” transmission/transaxle design, because the P1776 code is manufacturer specific to Chrysler. All that code means is that the low/reverse solenoid isn’t in the position it’s supposed to be in. Since solenoids are electrically actuated, you could have a circuit fault somewhere in the solenoid pack, relay center, or wiring harness which doesn’t happen until temperatures rise. The solenoid itself could be bad, but doesn’t trigger until it warms up (thermal expansion.)
http://en.allexperts.com/q/Chrysler-Repair-807/2009/5/P1776-Code.htm
The filter screens in the solenoid pack could be getting clogged, but it takes a bit of driving to recirculate enough “gunk” in the fluid to block the screen. Heck, P1776 is sometimes even a “false” DTC caused by the transmission running too hot:
Just an FYI, you do not ever put anything except ATF+4 in a Chrysler Ultradrive transmission.
I would suspect a change in fluid pressure from cold to hot.
I think what I asked is clear after the first two posts, and Honey badger’s explained it pretty good as well.
Thanks for the last few posts, some good thoughts. I did take a look at the links, and the one regarding the temp being incorrect causing the false 1776 code is interesting, and scary.
So, do you think replacing the atf+4 fluid with a fluid that is viscous enough under the required temperature change would prevent the sticky valve? Assuming such a fluid exists, and assuming the valve is actually sticking.
I’ve already explained to you that your problem may very well be something other than a valve that is physically sticking. Your evasiveness is not doing you any favors here. You have a problem, you’re looking for solutions, and you’re doing your damnedest to make it as hard as possible to help you.
I’m done here.
I don’t think it would be wise to try that. (Gentle-speak for DON’T EVEN THINK OF IT.)
While I generally agree with the advice to not use anything besides ATF+4 in transmissions that call for it, there is one brand of transmission fluid additive I would trust, and that is LUBEGARD. Their Platinum additive might help with your problem. Call them and speak with one of their consultants to get a more informed opinion.
I’m not a transmission expert but my perspective is from over 40 years of professional experience in auto repair.
Gary,
the reason I implore people to never put anything but ATF+4 in Chrysler transmissions has to do with the friction modifier properties. The UltraDrive architecture was one of the first to move to direct electronic/solenoid control, and the control strategies assume the properties of ATF+4. The Ultradrive architecture directly controls clutch and band brake engagements, and assumes the friction modifying properties of ATF+4. when you alter that by dumping in random additives, you change the amount of “slip” in the clutches and brakes, and when things don’t appear to be working right the TCM freaks out and puts the car into “limp home” mode. Then you (not you personally, but the general you) experiences this freak-out, and assumes the problem is the piece of junk transmission and not the dodgy “miracle fluid” you just dumped into it.
Hi, jz. Understood and agreed. I wouldn’t consider using any additive other than a LUBEGARD product, and wouldn’t even use that unless I was assured by LUBEGARD that it was appropriate and would not cause the problems you mention. The reason I trust this brand is that it’s the only one I know of to be recommended by a car manufacturer in a technical service bulletin.
I generally avoid additives for the normal reasons (if it would really help the manufacturer would use it, some of them can do harm, etc.). The only other one I have confidence in is Techron fuel additive, which is sold by some auto manufacturers packaged as a house brand.