legendary1

Hey guys, I have a 95 LS400 that I just bought and it is a dream. However, I am having some issues and I need your advice. It throwing a code of P0770 which means shift solenoid and my Lex Technician told me that it is a possibility that the solenoid could take care the problem or just ultimately be indicating a rebuild. The car shifts great however in the mornings when the car is still cold I presume, when I slow down it seems the the car vibrates greatly from the drivetrain and then when I take off after that vibration it seem the car stutters or hesitates . Yet, it will only do this in the morning usually and will not happen through out the day. My question is can a bad ecu cause a code like that? The reason why I suspect the ecu is because supposedly the former owner had a used transmission put in prior to me buying the car? Theoretically how long can a ride with this code and does it do any further damage to the car? Should I replace the solenoid or start saving up for another transmission or perhaps another car? Thanks guys for your input and advice I really need help.

RA40

iTrader: (6)

Welcome to Club Lexus.

Additional info needed: how many miles on car?
The P0770 is obvious. What condition is the tranny fluid? I hope it has Toyota Type IV or compatible. The wrong fluid or improper fill levels is a big cause of transmission issues.

Bushing wear can also attributable to vibrations. Carrier bushings, tranny mount and engine mounts.

legendary1

Thanks RA40 for the reply, the fluid is beautiful red and shows no sign of being burned and no slipping whatsoever, is it theoretically possible for my ecu to cause these codes because i have an 02 sensor code also?

LScowboyLS

YES!!

on my '96, my ECU got so bad the car would not even automatically shift AT ALL - but it had the misleading symptom of solenoids, because I could still shift it just fine manually!

The ECU caps were bad, now it shifts perfectly and no codes!

legendary1

Thats what I was thinking Cowboy and thats what im going to try first i know alot of people say a tell tale sign of a bad computer is the a/c does not engage but mine works fine, what were some of your signs leading to a bad computer and did you just replace the computer or did you have the capacitors rebuilt? Thanks alot for your input because i am really stressing

LScowboyLS

I replaced the capacitors myself, my thread on this tells the values you need and what type of capacitors to order (low ESR type, 105C temp rating, and brand should be Rubycon or Nippon Chemicon, or Panasonic, or Nichicon) and even gives step by step instructions on the repair in post #11

Attachment 501425Attachment 501695Attachment 501426Attachment 501695Attachment 501428Attachment 501695Attachment 501429

a junkyard ECU would have the same problem

the cost of all the capacitors to my door was less than $16

you can do this yourself if you are good at soldering!

the thing is, even if this is not the problem, it *will* be a problem soon, all Lexus's from the 90's have this issue, it is a ticking time bomb, so fix it regardless!

vermont

iTrader: (1)

Hi,
I'm having the same code p0770, and leaning towards replacing the capacitor. Question, do I need to have the ECU reprogram after replacing the capacitor?

steve2006

No reprogramming is required after the capacitor replacement,just make sure whoever does the job is competent at soldering and handling printed circuit boards.