<!-- from fixya rte -->How to free up sticking valve - 1999 Ford Mustang Cobra

Insure the throttle cable is free and not sticking, and that throttle valve is closing all the way.

Start your vehicle and keep your foot on the brake. Move the transmission lever through the entire range of gears including reverse, several times.

Then check the transmission fluid level.

It doesn't sound as though you have too much to worry about. Valves in a transmission unit can become 'glazed' and sticky. When this happens they don't open and close at the correct pressure/speeds.

If need be, repeat the same process with your foot on the brake and the vehicle in D. Give the engine a few revs, but keep your foot on the brake... you're trying to build up gearbox pressure and move a sticking valve.

If there's no improvement consider using a gearbox additive - there are many on the market which will free sticking valves - and take your vehicle for a test drive.

sticking valves will cause a bad miss in the engine. What it may have is a loose valve seat insert that is coming free as the head heats up. IT may be picked up by a compression test on a hot engine . The insert follows the valve in its movement hence the intermittent knock
I would have it checked out at an accredited shop that handles your make of car.

a lot of different things can cause brakes to stick. i need more info?? did you jack it up and check to see if tires free spin with normal pressure? is it front or back? is it one wheel or two??

It sounds like your valve body may be sticking. If it is, this is usually caused by debris getting into the valve body and causing the pistons to stick in their bores. This can cause an internal hydraulic leak and the symptoms you are describing. Unfortunately, this usually results in a transmission overhaul because the debris that makes the valve body stick usually originates from clutches and other parts that are damaged or badly worn.

This is a known fault with new shape A6's. The heater control valve (located within the bulkhead within the engine compartment) sticks thus causing hot air to vent out of one side whilst the other side stays cold. Audi have issued a Technical Service Bulletin (TSB) regarding this problem and if your car is within its warranty period they will repair free of charge - if not you are looking at a cost of £250 for a new valve. In true Audi honoured tradition they don't admit to the problem being a design fault despite new valves being modified to prevent it happening in future!! A temporary solution is to turn the climate control dial to max (Hi) then to min (Lo) which should free the valve off until it sticks again. Details and a picture of the valve can be found on the audiworld forum

FIRST CHECK TRANSMISSION FLUID LEVEL MAKE SURE ITS CORRECT.IF FLUID LEVEL OKAY SOUND LIKE STICKING SHIFT VALVES.CHANGE TRANSMISSION FLUID + FILTER.GET SOME TRANSMEDIC ADD 1/2 TO NEW TRANSMISSION FLUID THIS HELP FREE STUCK SHIFT VALVES IN VALVE BODY DONT OVER FILL ADD IT IN.BUT DONT OVER FILL TRANSMISSION.IF THIS DONT HELP.YOU COULD HAVE VALVE BODY PROBLEM.

This may work for you. They used to have a product in the 50s and 60s called top end lubrication (A.K.A. marvel mystery oil). You can use marvel mystery oil in your fuel and it will help free sticky valves.

Here is something else you can try and it may work better and it is cheaper. Go to walmart and buy some marine rated 2 stroke motor oil. (supratech 2.99 for like a quart). Mix 1 once per five gallons of gasolene into your tank. This will lubricate the entire top end of your engine which may free your sticking valves. This will also clean the entire fuel system and injectors as well as drying up any moisture in your fuel system, it will also help to remove carbon buildup from the top end of your valves which is probably why they are sticking. It will not blow blue smoke out the back of your exhuast as long as you adhere to the above ratio. If you put too much it in won't hurt it. You will see the results after you use it for a few tank fulls.

You should get an increase in fuel mileage and power using this because it will clean up your fuel system really good. Good luck to you.

most people say no to a high mileage transmission flush if it hasnt been done before on the vehicle, I say if it starts to slip then flush it but if it is just sticking whop the old lucas trans mission oil to her! they have it at advanced it should free up those sticky valves! but if you havnt flushed it before now i would'nt
it is believed that over time your transmission fluid gets "gritty" from the clutches wearing , and over time your transmission becomes reliant on that grit to run "smoothly" I've done it and it came out fine but that was due to slipping from thin or burnt transmission fluid,
I would really try an additive to free up the valves before i'd do a flush!

The trans in your vehicle is a 3 speed auto,A904 model,also designated the 30RH or32RH.The trans is totally hydraulic,no electronic controls with the exception of tcc apply,aka,lockup.The vehicle shifts from throttle pressure and a governor.The governor is inside the tailhousing of the trans and is responsible for the road speed signal in this trans.If the valves in the governor start sticking,the vehicle will take off in 2nd gear.The valves can be cleaned,and sometimes jarred loose,but the more pressing concern is why are the valves sticking?The valves will start sticking when other parts of the trans starts making metal.So the governor sticking can sometimes be the symptom of a larger problem.Pull the trans pan and look for metal,and if so, how bad?One way to clear the governor of debris is to find an abandoned road or parking lot.At a complete stop,engage Reverse gear,and back up as fast as you dare.I have backed cars up at 20-30 mph before,but wouldn't recommend you to.This can blow debris out of the governor hydraulic circuits,and free the governor valves as highest line pressure inside the trans is obtained in Reverse gear.Good luck.