i got these codes and cant really find a definitive answer. anyone get these codes before?

 

P1755 = Intermediate Speed Sensor (ISS) Malfunction
P1765 = Linear Shift Solenoid Circuit Fault

what year car? and what mileage are you on?

 

Are you sure on this?
I'd rather check the "Lock Up Linear Solenoid" when at P1755 or the ECU.

 

Its 97 ls400. And about 180k. I followed your ecu rebuild guide because i had 32 codes. Not sure if these two codes were there before i did the ecu but are they only codes that are coming up after the i did the ecu

 

P1755 is referring to the "Lock up Linear Solenoid".
P1765 is referring to the "Clutch Control Solenoid".
I wonder why Timmy wrote about an ISS.

Anyway those codes indicate that solenoids above are open or short circuited. Sometimes connection issues or an failed ECU also generates random codes. So you need to distinguish which is causing the problem.

Do you have any AT problem now?
If not, simply erase those codes using a scanner. Judging from your situation reporting P codes, you are in use of a scanner. Codes stored in the non volatile memory can't be erased by a battery disconnection.

If the codes are coming back, you need to check solenoids, connections or the ECU. Did you replace all ECU capacitors properly?

Inform me the result and I'll give you a next step to do.

 

sounds like dead trans solenoid or solenoid wiring harness.

 

I'm getting these codes and P0770 Shift Solenoid E. 1997 with 138,000 miles.

When I clear these codes with a scanner they come right back, even before starting the engine or shifting out of park which suggests the solenoid is stuck ON. Transmission shifts more firmly than it should, into reverse as well as thru the gears and down shifting, especially when slowing to a stop, 2nd to 1st..

I recently replaced all 6 of the capacitors in my ECU. I also replaced the Traction Control module due to another issue which is now cleared.

Can I check to see if this is a wiring issue or something other than the actual solenoid?
Are there any other ECU upgrades/repairs/mods I need to do for this issue or in general?

 

Sounds like you've answered your own questions. If you have access to a toyota dealership scanner you can have them run some advanced diagnostics that are otherwise inaccessible through normal OBDII scanners. It could be either a dead solenoid or an issue with the harness. on that generation transmission I would lean towards solenoid.

 

Thanks for the info.

Are there any good aftermarket solenoids or should I just go with genuine Toyota?
I think the best price I've found is $225. Any suggestions?

 

For trans internals I prefer OEM

 

Where do you like to shop for OEM parts?