transmission shifts hard
5.3 L engine (from 2002 Silverado) with a 4l80e transmission shifting hard from 1st to 2nd
gear. All other gears shift normal
Could be the solenoids. When was the trans serviced last? You might want to take it by a parts store that can check the codes, look for any transmission codes in the memory, hopefully there will be some there and that would give you some place to start.
Did the parts store thing and no codes. Filter and fluid changed 2+ years ago. It looks clean on the dipstick. Read somewhere it might be the TPS (Throttle Position Sensor) so I'm going to try to check that out tomorrow. Ever hear of that?
It is possible that the throttle plate could be dirty and throwing off the initial setting, have you cleaned the throttle body lately? Usually if the TPS is bad it will throw a code, but I have seen TPS sensors have a brief open in them that the ECM will not pickup on.
I plan on cleaning the throttle body before changing the TPS. I'll let you know what happens. Thanks
Cleaning TPS/body didn't work. Still not getting any codes except Mass Air Flow sensor voltage high. Could that be it?
Clean the air flow sensor also, check the minimum air rate, reset if needed, then reset the ECM and roadtest if the check engine returns with the same code, check the ECM's sensor voltage to that sensor, if the ECM's voltage is at 5 volts or just slightly below at the sensor then check the sensor ground if it checks good then replace the sensor.
Thanks shoes. I tried cleaning the sensor and didn't help. I'll try resetting PCM and see what happens
Found problem. Broken wire from PCM to transmission shifter (connector on top of shifter) ground wire broken and power wire barely hanging on. Ops check good.
Soo much for "experts" at AAMCO and McCarthy's transmissions in Newport News Virginia. Told me it needed rebuild and or replacement. CROOKS!
Glad you found the problem, that seems to be the problem with a lot of the major repair places, just jumping to conclusions with out doing a full diagnostic first. I have found through the years that poor grounds and power supplies cause more problems than actual component failures. But that still don't explain the air flow code unless it's ground was at the same location.
Mass Air Flow sensor is "disconnected" by my son-in-law. He has some kind of "electronic tuner program" (hooks to his laptop). He has that and 2 O2 sensors disconnected (no catalytic converter installed). I have him sending me the program and cable now so I can figure out hopw to tune up the truck. New fangled gadgets drive me crazy.....lol. Thanks for your help
I have a 2000 that shifts hard 1-2 only sometimes idk what it is
acborden that sounds like the same most everyone is having with the sticking shift solenoids.
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