2004 4.7 throwing P0778...help

[Panda96]

2004 with 4.7 throwing rarely seen (apparently) P0778. I did knowingly buy it like this. Only has 200K on it and is in great shape other than this. So I rolled the dice based on as much research as I could find. I'm scheduled to have my Master Certified Toyota mechanic dig into it on Jan 18th. Hoping the tranny doesn't fall out before then of course

It drives perfectly fine until you hit 10mph speeding up or slowing down. Then you get a hard hiccup. Only does it around 10mph. No grinding or weird noises. Just a hiccup.

Does anyone have any experience with this at all? Was told it could be a solenoid.

Thanks

 

[AuSeeker]

2004 with 4.7 throwing rarely seen (apparently) P0778. I did knowingly buy it like this. Only has 200K on it and is in great shape other than this. So I rolled the dice based on as much research as I could find. I'm scheduled to have my Master Certified Toyota mechanic dig into it on Jan 18th. Hoping the tranny doesn't fall out before then of course

It drives perfectly fine until you hit 10mph speeding up or slowing down. Then you get a hard hiccup. Only does it around 10mph. No grinding or weird noises. Just a hiccup.

Does anyone have any experience with this at all? Was told it could be a solenoid.

Thanks

If I'm not mistaken that code relates to the B solenoid.

One thing that I would suggest you get your mechanic to check is the wiring connector where it plugs into the side of the transmission, the connector/terminals have been known on a few 4Runners especially on some from the rust belt/snow belt to corrode and causing a bad connection which can cause shifting issues.

 

[Panda96]

Thank you!

 

[03blkrunner]

Hey Panda96,

I know this is an old thread but I've got the same code now with same symptoms on my 03. Did you ever figure this out? Seems like by doing diagnostics it's likely the solenoid on mine but seeing how faired.

Thanks

 

[AuSeeker]

Hey Panda96,

I know this is an old thread but I've got the same code now with same symptoms on my 03. Did you ever figure this out? Seems like by doing diagnostics it's likely the solenoid on mine but seeing how faired.

Thanks

Panda96 hasn't been back on the forum since his last reply in this topic over 2 1/2 years ago, so he most likely will not be replying.

Have the electrical connector check as I suggested above, it is a far more common failure point than the solenoid, especially in the snow/rust belt.

 

[03blkrunner]

Yeah, I noticed that. Wasn't sure if meant hadn't visited or hadn't posted. I tend to search/lurk far more than I post.

I pulled connector at ECU to check ohm readings. I'm getting correct readings above 1MΩ for SL2- / + to body but SL2+/- I'm getting .8MΩ; target is 5Ω. I can try to check on the transmission side to confirm if it's the wire but that's some gymnastics to get a probe into that connector (that I also broke the clip on!). Truth be told I'm hoping it's the solenoid as it's a far easier fix than replacing the wire!

Background if interested: Issue started when I was a few minutes from the house pulling the camper. I'm looking at dropping my truck lease as I really only "need" it for pulling our camper (Jayco X213: ~5,000 lb loaded) so 4Runner would have to pick that work up. As my 4Runner is old enough to drink now I took out on a quick 40 mile trip, back roads and some high way the night before heading out. No problem (other than I have dreaded 4th gear detent issue so have to hold over the whole time). Go to leave the next day and get the code about 10 miles out while going down 55 mph back road. Watching transmission and engine temps I didn't have any issues (Trans maxed out at 200). Other than no 5th gear and the rought 2->1 shift it acted completely normal. I have 150k on the truck, no other issues ever like this (I'm not naive that age isn't going to bring more break downs). Since it appeared right at same time as time as I started towing figured might be related. Or could be rodent got to wire shield and the extra heat caused it to melt, I'm not sure.