How to flush valve body???

Hi, I did my 09A auto solenoids (all 9 Japanese Cobra ones) a few months ago for the notorious solenoid failure this 09A has. Short story, I had about 3K miles of trouble free service. It was great. A few months ago, I started having to wait for the car to warm up, before it would shift from 1 to 2 (or 2-3 if this car starts in 2nd?).

I trouble shooter these symptom with a few members on here and think some gunk must have broke loose and stopped up the N92 or N89 solenoid. The price of three individual solenoids from Cobra is close to another whole 9 pack, so I just bought the 9 pack again (with plans to only change the N92 and N89, since all other shifting is perfect).

I plan on doing the solenoid change on the car again, it's tight, but doable. How can I flush the passages where the N92 and N89 plug into?

1. Is there a way to do it in the car?

2. Would it be better to remove the valve body and flush it for a more thorough job?

3. While I'm in there, I know my trans temp sensor is bad. CoolAirVW is the guy for the replacement info from what I hear. I instead of buying the expensive VW one, would splicing in a cheaper OEM sensor, say from a KIA, work too? It's only $18.00 as opposed to $260 is it is JUST the sensor and NOT the wiring...

I don't want to mess with this again until I have the $ and time to do a manual swap. Thank you for your advice!!!

In your discussions with other members how was the fact that it shifts after it warms up reconciled. If your going to manual swap it anyway just return the solenoids (300) and get a swap kit (1000) or buy a wreck for less than 1000. That 300 is never coming back.

Lubeguard makes a transmission flush. Don't have much info but decent reviews on Amazon.


As for the temp sensor, get the original. I doubt anything made for other transmissions will fit.

drucifer- After it warms up, shifts perfect. The manual swap is a long ways away. Around me, a decent enough swap candidate is going to be $1200. That's a big difference from $300 in solenoids. Plus I'm in an apartment not and don't have access to a facility to do that level of work. I'd want to get a parts car, and keep it for other parts I'd need in the future. So I'm saving that project for 1-2 years when we are in a house again.


alex_tdi- "As for the temp sensor, get the original. I doubt anything made for other transmissions will fit." Can you elaborate why you feel this way? Both sensors have two wires (even CoolAir VW's short cut requires splicing it in-two wires for the VW one too), both are for car that run temperature ranges not far off from each other. See where I'm going?

I'm waiting to hear back from CoolAirVW for his advice. Since mine is already broken, and if CoolAIrVW confirms the sensor is what goes bad (not the wire), I'd happily be the experimental test car. Heck for $17, why not. I might save forum members $200 if this works.

I'll keep you posted on what he says about the sensor and what I decide to do. I'll looked at that brand flush you mentioned. It seems its for the cooler (you disconnect the trans cooler lines, in and out) and just flush the transcooler by it self? I'm not sure I want to a whole flush. Heard bad things happen there. I just want to flush the valve body (or the affected solenoid passages).

I'm thinking is that since the temperature sensor is inside the transmission, you need to make sure that 1) it fits in the exact space designed for it, 2) it mounts securely, 3) it doesn't impede fluid flow, 4) it provides the appropriate resistance/voltage based on the temperature, 5) the material is compatible with the ATF's chemistry.

I'm not sure if the temperature sensor is resistance based or voltage based or inductance based or something else. If you can figure that out and also find another that performs just like it (i.e. put out the exact voltage, exact resistance/inductance, etc.), then theoretically it could work.

Maybe others have already figured this out, but just a lot of unknowns to me.

Hi Alex!

I think these are the only things that matter from your lis: 4) it provides the appropriate resistance/voltage based on the temperature, 5) the material is compatible with the ATF's chemistry.

More 4 than 5,

This could also be a important matter "I'm not sure if the temperature sensor is resistance based or voltage based or inductance based or something else. "

I'm not sure there. Waiting on CoolAitVW's response. His regular shortcut has you mounting the sensor just off a solenoid or valve body bolt (make shift mount). So 1,2, or 3 aren't an issue.

Great thoughts and input!

Fair enough. Good luck.



I can understand your motivation. I'm of the opinion that VW/Audi parts are really overpriced as well.

After reading more about CoolAirVW's threads, I don't think it is even worth fixing (noticeable drivability). I'm going to to do without it for now.

I would just drain and refill with fresh ATF. Match the volume of the new to the old for starters.

I've been reading up on ross-tech's code 00652 symptoms.

1. I've checked my ATF (having to work around the failed trans fluid temp sensor with a new laser temperature gun checking the outgoing fluid). The fluid it good, only about 2-3K miles old, and the correct VW fluid=not the problem

2. I checked my transmission range switch. The index marks were not aligned perfect (my fault from when I did the solenoids). I corrected the switch and the marks all align. However, that still did NOT fix any drivability problems.

Does "basic adaptation" need to be done or some other sort of reset once adjusting this switch (Keep in mind, the battery was already disconnected during this procedure).

Next items to test according to the ross-tech page:

-G68 sensor (sensor or wire)

-G38 sensor (sensor or wire)

-Valvebody faulty (possible, but most expensive so last item to check)

-ATF pump faulty (not likely, shifts fine when warmed up)

I have the Bentley's with my VCDS, but I'm having a heck of a time trying to find the pin out diagram for the TCM? The Italian made Bosio TCM, doesn't have a diagram. Only section numbers, like 50/55/60/65 etc.

I saw a video somewhere about the importance of torquing the bolts "just right" on the valve body. 1 ft/lb over and the valves got stuck.

If you're using a click-type torque wrench, perhaps you should recalibrate it and re-torque all the bolts (in the factory-specified sequence and torque). Some others have actually said they use a beam type torque wrench, although I don't know if that's more accurate than a calibrated torque wrench or not.

alex_tdi said:

I saw a video somewhere about the importance of torquing the bolts "just right" on the valve body. 1 ft/lb over and the valves got stuck.

If you're using a click-type torque wrench, perhaps you should recalibrate it and re-torque all the bolts (in the factory-specified sequence and torque). Some others have actually said they use a beam type torque wrench, although I don't know if that's more accurate than a calibrated torque wrench or not.

Click to expand...

That's on Kansas City TDi's website, and I think it's more for the 01M gearbox.



It could be your solenoids you received are faulty, does Cobra offer a warranty on them?