Dreades P0770 code has reared its head.

I reset the code and we will see how long it takes to return. My guess is about three to four weeks as I'm sure the seller cleared the code before he sold it to me. I should have run readiness on it but he had a recent smog test to go with the sale so I thought it's gotta be a green light on the reader.

So I've read and read this last hour and am thinking of just going right for the throat and changing out the torque converter. I've read, fluid change, valve body cleaning, lockup solenoid, etc.... but all those posts still had the code returning. The guy who changed out his TC on Yotatech got rid of his light.

If any members have any insight, please feel free to chime in. In the meantime, I'll make sure to do a DIY Video for the members.

 

New read and I'm going to work on the valve body first and serif that, sure the issue.

So fluid change and valve body, then TC is all else fails.

 

come on members, someone chime in.

 

Bump for any insight. Light has not returned but have yet to run a readiness test.

 

Rather than full send on the torque converter, seems like a good idea to just replace the solenoids, and see where that gets you, especially since you didn't mention other issues.

P0770 Code UPDATED 11/18/16 | Tacoma World
code P0770 | Tacoma World

 

Thanks for chiming in. Yea, I'm backing out of the full send. Now I'm just doing a valve body clean and adding the zip kit, full transmission flush and I guess adjusting some cable, which if I can recall is the kick down cable. That will be last as it might not need any adjusting.

Also learned something today is that the 1st gen tacoma does not use a transmission pan gasket, it's just silicone, from what my parts rep told me. Now I guess I'll get that Fel Pro gasket from my local parts store.

 

Be careful with the transmission flush. If your transmission is high mileage that can potentially cause more harm than good by dislodging gunk into your transmission.

Just curious - is the transmission behaving differently? Any symptoms?

 

@otis24 Good point.

@Raudi Driver before you dive into all this work, I'd actually suggest starting with a few drain and fills of the transmission fluid. Get some fresh fluid in there and see if that helps before going further.

Just drain what's in the pan, and add back until the dipstick is right. Most folks measure what they catch and add exactly that amount back, but I suggest you add closely that amount, but use the dipstick at the source of truth. It currently could be over or under filled (even from the factory). Do a few (three ish) drain and fills over the course of a 1000 miles. "mixing" fluid is ok in terms of replacement fluid vs whatever is in there. Most folks (myself included) run MaxLife synthetic ATF.

 

Ok, great, that's what I have and I was planning on running some fresh fluid through the transmission. I wanted to drop the pan and do it all but since the fluid is so cheap, I'll start with 2 flushes first then move in for the kill if needed.

The only reason I'm doing this is because of the light, which has yet to return. I'll check for a readiness green light today but I'm assuming it's still yellow and will pop back on.

The only issue I'm seeing is the idle on cold start is high and doesn't go down for a few minutes.

 

Can you give an update on your situation?

I "won" an auction for a 2001 Tacoma on BaT a few weeks back, picked it up yesterday. 3 hours into my 7 hour drive the CEL came on and was code P0770. I made it the rest of the journey home no problem. Never felt any weird shifts. It was owned by the same guy for 21 years and is in great shape, seems like he took care of it so probably bad luck. Anyway, I am just diving into the reading on this and just curious if your minor fix worked long term.