Just bought this '97 Catera with 57,000 miles and it was a challenge to get it the 30 miles home. Seemed to delay 1-2 upshift and couldn't get 3rd for a while. Also seemed to be slipping sometimes. Went into limp mode after a while into 3rd so I dreaded every stop light but at least could go 50-55 now. Anyway, when I got home and scanned it, only has code P1870 for TCC stuck off. I'll check the fluid first, but no dipstick on these. Then I guess I check the TCC solenoid? Is there a resistance spec? And if it's supposed to be either on or off, can I put 12V and ground to the pins and see if it works?
4L30E transmission with only P1870 code
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JTK
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I wish I could help with the P1870 code, but I do have some maintenance experience with the 4L30E. This same transmission was used in 1998-2004 Isuzu Rodeos and Troopers. You have to check fluid level from the main pan on the trans. You'll see what looks like two drain plugs. The one that's stamped up high into the pan is the level check, refill plug. There is a small adapter pan further forward w/ no plugs on it. Ignore that one. With the vehicle idling at normal ops temps, fluid should just dribble out the level check. You pretty much need a lift or a pit to drive over for a low to the ground Catera unfortunately.
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TCC wouldn't cause the symptoms you describe. Low fluid might. How long did it sit? Maybe internal seals dried out.
Don't know how long it sat but a timing belt sticker shows 4 years ago it had 4,000 miles less.
Don't take the P1870 code description (TCC Stuck Off) literally as this code can set ANYTIME the commanded ratio & actual ratio are different.
Until you get it to shift through all 3 gears without drama......Ignore the P1870 & clear it out after any repair attempt as it will freeze shift adapts. (Yes....I know it's a 4 speed. I don't count 1st gear as a shift)
Check the fluid level as was already advised! If it's really low, Add fluid then test drive. If it now shifts better......
Drop the pan & change the filter, Add fresh Dexron III or VI along with some Lubegard Red additive per the instructions.
With a car that has sat awhile.....I use my OTC 3398 Injector Pulse Tester set to 100 pulses/5 milliseconds to clean each solenoid after the dose of Lubegard Red. Fixes sticky solenoids @ 95% of the time. Some transmission shops have dedicated equipment that does the same thing but generally only use it when they have an warranty issue with a rebuild, Rarely do they care enough to fix a "Customer Pay/Non-warranty" issue with it!!
Until you get it to shift through all 3 gears without drama......Ignore the P1870 & clear it out after any repair attempt as it will freeze shift adapts. (Yes....I know it's a 4 speed. I don't count 1st gear as a shift)
Check the fluid level as was already advised! If it's really low, Add fluid then test drive. If it now shifts better......
Drop the pan & change the filter, Add fresh Dexron III or VI along with some Lubegard Red additive per the instructions.
With a car that has sat awhile.....I use my OTC 3398 Injector Pulse Tester set to 100 pulses/5 milliseconds to clean each solenoid after the dose of Lubegard Red. Fixes sticky solenoids @ 95% of the time. Some transmission shops have dedicated equipment that does the same thing but generally only use it when they have an warranty issue with a rebuild, Rarely do they care enough to fix a "Customer Pay/Non-warranty" issue with it!!
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