New here but got a lot of help from you all reading through the site. Having an issue with my 2002 expedition 4r70w trans.

Has a problem blowing fuse 23 putting the trans in limp mode. Long story short the 02 sensor was grounding out on the heat shield by the cat on passenger side. I got this part straight now.

Since fixing this now when I got to drive I have to give it a little gas to get it to engage in gear. After that everything is fine. When I go around a turn it drops to neutral and I can rev it all day but stays in neutral. I have to come to a stop and it goes back in gear. Almost like it has no idea what gear to be in as slow I around a turn. I did a stupid thing because I was stuck 2 miles in the woods. When the fuse blew. So I put a piece of foil over fuse 23 to keep it live and get me out of the woods. I think I fried something doing that because prior to this the truck ran fine so my thought is electrical. Has 170,000 miles well taken care truck it's my wife's so it does local driving and that's it. Fluid is good new neutral safety switch. Any ideas? My thought was maybe I shorted out the TCM since slowing around turns it drops to neutral and has no idea what gear to be in until I come to a stop. All help is greatly appreciated. shows 3 codes but nothing related to this issue

 

There is nothing electrical that can do this. It has to be either low trans fluid, a loose/missing internal filter, or a mechanical failure inside the transmission.

 

Transmission codes or engine codes?

 

Thanks for the repliesOk my only reasoning on it being electrical is because it was perfectly fine until the fuse blew several times and then to get out of where I was I bypassed the fuse. Immediately after this is when the issue started so thought maybe something got fried. What would cause me to have to tap the gas to get it to engage and for it to drop to neutral around turns and me to have to stop completely for it to rein Gage?

Only codes I get are egr and o2 sensor but nothing trans related.

 

This didn't answer that question for you?

 

Seriously, check the easy stuff first

 

No that did answer my question to an extent I was just explaining why I thought it was probably electrical. What I was asking was in reference to mechanic failure. What would typically be the type of failure a clutch? If the simple things don't fix it I'll replace with a junk yard trans I just wanted make sure it wasn't a bad TCM or solenoid first that's all. Fluid is fine was changed not long ago. I'll drop pan and check filter. Thanks for the help

 

Took it out for a ride today was going to do filter n fluids but didnt get to it. Anyway with over drive off I dont have the issue going around turns. It shifts as it should. With overdrive on it goes to neutral and I need to stop to get it to engage in hear. What would cause it to work fine with overdrive off?