plova

I need an opinion on what I should do with my A6 with the ZF5HP19A transmission. To make a long story short the transmission went, got a used one with 80K on it, had a garage pull the old one and when going to put the used one in noticed the same problem starting to occur in the used one (bushing pulling off between the converter & Pump) so took it to a specialist who took the used one apart, went through to check all clutch packs, etc.( everything good) and then added a new TC and pump housing as the pump was good. Took it back to the shop and had it put back in and it would not engage in any gears. Mechanic thought no pressure. The rest of the story between tranny specialist & mechanic too long to get into.

I have had it home for a few years but finally thought about seeing what could be done. I have run a VAG-COM for diagnostics and found no error codes. At first the car was in neutral but now it seems to be in 1st ( in all selections according the VCDS). I brought the transmission up to about 30C to see if any pressure would build up but nothing. At the same time I took readings from the measuring blocks and it seems that all Solenoids have voltage ( between 0.14 and 0.65-0.74) approximately. I have also run an output test and found when running this that the pressure valve solenoids (216, 217 & 218) do not emit the clicking sound that the others ( Shift Solenoid & Pressure Solenoid 115) do emit a clicking sound. Also the transmission power relay emits no sound but I don't know if it does normally ?

I drained the fluid today and removed the pan to inspect. The new fluid was a bit discolored and there was some particles on the magnets but nothing like when you do a regular service. The fluid almost has a bit of a brown tint but I don't know if that was because it had been sitting so long ? The drain was just over 2 liters which surprised me as I thought there should have been more. There were 9 liters used to fill since the transmission/TC was completely drained since it was disassembled..

I am now trying to determine if it is worth while getting a functioning valve body to see if that will solve the problem (due to no response from the 3 pressure solenoids) or to just scrap the car because the problem is mechanical (ie. fluid pump, incorrect installation or TC). I understand that a functioning, used Valve Body is less expensive than the solenoids.

Any opinion, suggestions or recommendations greatly appreciated.

Thanks,


Jeff

Airbag

stupid question .... are absolutely sure it was filled properly .. ? its amazing how much more it will take as it starts to warm up and you fill it while steping through the gears..

plova

Hi Airbag,

Actually a good question that I am beginning to wonder about as well since I did not do the service and only two liters drained out. At least they had it noted on the invoice that it was filled with 9 liters. I know when I did the service recently on my Tiguan the sites I researched said to expect between 4-5 to be drained and just over 4 drained and I did the normal fill procedure and drained off the excess and everything was fine. The Audi sites mentioned around the same should drain, even a bit more.

I was going to clean and then try to refill by go through the standard procedure like you mentioned except for the fact that the solenoids didn't seeming to be responding (216,217 & 218) when I did the output test. I guess the easiest thing to do is to clean and then refill to make sure there is enough in the transmission. I guess it is a toss up as to try this or try a functioning valve body with a refill. The main question would be that if it is a malfunction with the valve body (pressure solenoids not working) then would that prevent the transmission from even working in limp mode when the unit is disconnected from the TCU ? As I understand the transmission is suppose to go into limp mode but it doesn't (display lights up in all gears but no wheel movement).

I will probably try the refill to correct level as 5-6 liters of fluid is less expensive than a used but functioning valve body !

Thanks,


Jeff

Airbag

yeah I think try with the easy stuff, not necessarily cheap tho . But maybe the valves cant build pressure because there is no fluid ) .. just a thought.


would be a real kick in the nads to find out it was just low all this time .. ouch !!!

plova

Yeah, I hear you ! Just thinking About $85 for the fluid (Pento) v.s. $200 or there about for a used but functioning valve body. If it was just due to the fluid being low then very frustrated but relieved !

Trying to get this on the road as I have a daughter getting her permit in about 4 months, another 14 months behind her and my son has had his license for 4 months now. Thinking it would be a good car to learn on and if something happens not a big issue.

Will update when I get it figured out.

Airbag

yup that's what I did with my A6 .. they seem to have all been demoted to learner cars ( big heavy and safe ) . My son just finished his first year with mine .. and off to the wreckers she goes next week.

Prospeeder

So with the engine off, add fluid, when it comes out, start the engine. If it doesnt take any more fluid, you know the pump is not working and they screwed up. It should take about 3.5-4 quarts off, and then another 1.5-2 quarts while running. Dont worry much about what fluid you use, most synthetic multi vehicle ATFs like Valvoline maxlife ATF work great and are like 5$ a quart. For all you know its junk anyway.