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Infiniti G35 Solenoid/Valve Body

Hi,
I had a check engine light come on on my 2004 G35 and I took it to the dealership to have it checked out. They came back with a code of P1760 and said I would have to replace the automatic transmission valve body and gave me a cost estimate of $1550.
My understanding is that the solenoid valve controls transmission fluid and should be pretty cheap to replace. But I don’t know why I would have to replace the whole valve body? My car is not giving me any issues with sluggish shifting when I drive or going into a fail-safe mode where it wont shift into higher gears etc.
My question is, should I do what the dealer is saying or do I have better options that will also save me money like buying after market from Stillen etc.
Any help or suggestions would be greatly appreciated.

nope Nissian haas had issue with valve bodys in different cars you can try taking it to a local transmission shop not one of the chain shops for a second opion

Go for a second opinion, as is always prudent when quoted a large bill. The problem is that these valves are all contained in a single assembly. I’ve attached a document for my own car as an example. Unfortunately, I don;t have access to Nissan drawing.

http://tijil.org/Scion_Docs/05_tC_Shop_Manuals/Repair%20Info/Repair%20Manual/Automatic%20Transmission-Trans/Transmission%20Valve%20Body%20Assy/x040001.pdf

Mo, there are several fixes for this valve body. What exactly is the transmission doing?? A valve body for this transmission LISTS at $1600 and some change. Is it doing anything at all or is there just a code there??

transman

There was just a code. I haven’t noticed any delays or skips while driving as the engine shifts through gears but I am told that is what will eventually happen if I don’t replace the valve body.

A local trans shop told me that Nissans (Infinitis) have an issue with the radiator leaking into the transmission? I am going to drive it for a few more days and see if the check engine light comes back on as the computer runs its checks since the dealer reset the CPU memory so they couldn’t run any diagnostics on it.
Transman, at what point do you think it is a safe bet to just replace the valve body instead of trying to find someone to replace the solenoid that might have gone bad? I am not sure how much work would be involved.

Thats the best thing to do when you have no symptoms. Note the code/s, clear the codes, reset all shift adapts (Where applicable) and drive it to see if the code comes back. If a valve body itself needs to be replaced, the problem is mechanical, inside the valve body. (Worn valves/bores) Like I said there are several fixes for this valve body such as valve bores which require reaming and installing sleeves. The solenoids themselves are easily replacable

transman

So I was able to get a more accurate explanation of what is wrong. Basically I have a faulty Turbine Revolution Sensor. It is supposed to read the RPM and shift gears accordingly. He said it is possible that there is an oil leak over that is shorting the sensor and hence the engine light and the AT check light is coming on. He showed me the code of P1716 which seems to be accurate and then pulled a valve body from the back and showed me the motherboard and the two sensors on top of it. Apparently one can not order the sensors from the manufacturer (Bosch) and I actually could not find the item using its product number ( 0 260 550 002). And since they are sitting on top inside the valve body, there is no easy way to access them.

Here is the picture of what it looks like below.

http://softelectronic.com/media/k2/galleries/49/Picture%20031.jpg

My final question is, should I just bite the $1500 bullet to have the valve body replaced or is there a less costlier alternative or explanation of what might be going on?