Need Help with my 97 LT1
Thread Starter
Teching In
Joined: Sep 2009
Posts: 6
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From: knoxville TN
Need Help with my 97 LT1 I have a 97 Z28 with an automatic tranny and every time i start the car the SES light comes on and the car goes into limp mode. It runs in 3rd I can down shift to second but not 1st. If i let it warm for a few minutes and then erase the code with my scanner the light goes away and the car runs and shifts fine rest of the day. I can start it and turn it off a hundred times the light will not come back while the car is still warm but if i let it sit overnight the next morning it comes back and goes back into limp mode. by the way its throwing the codes p0785 and twice it has thrown p0161. any help or advice will help Thank You.
P0785 is the 3-2 shift solenoid, so it makes sense that it goes into limp mode. Have you had it checked? Also, the presence of the O2 sensor code could indicate an issue with your wiring harness, I would look there as well.
Thread Starter
Teching In
Joined: Sep 2009
Posts: 6
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From: knoxville TN
ok Yea I suspected the harness as well but I have no idea on how to get the harness into a place where i can see it most of it is behing the engine and above the tranny i have no lift. No before I bought scanner i changed the 1-2 solenoid because it had the symptoms of that but I now see the code as the 3-2 solenoid. But if its a solenoid would it work after the computers codes are cleared i would think a bad solenoid would just always be bad, not just when the engine is started in the morning. Do you think it could be a bad PCM?
I think the biggest thing thats throwing me off is that it only throws the code when its first started for the day. But if i let it warm up for a few minutes then erase the code its good for the rest of the day.
I think the biggest thing thats throwing me off is that it only throws the code when its first started for the day. But if i let it warm up for a few minutes then erase the code its good for the rest of the day.
If you can get to the solenoid, I would change it out because they are not that expensive, and it would eliminate the sensor itself as a culprit.
AFA the cold vs. warm, I agree that doesn't make a whole lot of sense, even if it turns out to be the harness. And debugging it won't be a lot of fun, as you have noticed already.
The last thing I would suspect is the PCM, they just don't go bad that often.
AFA the cold vs. warm, I agree that doesn't make a whole lot of sense, even if it turns out to be the harness. And debugging it won't be a lot of fun, as you have noticed already.
The last thing I would suspect is the PCM, they just don't go bad that often.
The strap on the trans harness that holds it to the bellhousing comes off and frees up the harness with out having to unbolt it if I remember right. You can then disconect everything under the car and fish it back up to the engine bay where you can open it and inspect it. Main thing is to just check that you get main power to the trans. I foget which wire it is but if it has good power then everything else is just signal wires.
Thread Starter
Teching In
Joined: Sep 2009
Posts: 6
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From: knoxville TN
Thanks Ok i'll check it out thanks for the help its had me stumped for a couple weeks weeks now and mechanics I've talked to don't have any clue about this car. They just tell me to start changing things because there is no diagnostic way of finding what's wrong with it. Which may be true but I would hate to waste a whole lot of money to find the problem.
Ok i'll check it out thanks for the help its had me stumped for a couple weeks weeks now and mechanics I've talked to don't have any clue about this car. They just tell me to start changing things because there is no diagnostic way of finding what's wrong with it. Which may be true but I would hate to waste a whole lot of money to find the problem.
