Apr 13, 2017 · The 4l80e has an input and output speed sensor. Gear can be easily calculated from these. The 4l80e also has actual gear outputs. There are switchs that indicate gear. Donnie needs to use the switch on the brake as his "clutch switch"
Automatic transmission speed sensor issues mimic some of the nastiest transmission problems. The difference is that sensors are pretty cheap to replace when compared to the hundreds of dollars you spend on other breakdowns in the system. If you're lucky, all you have to do is replace your speed...
Common problems in vehicles with a 4L80-E transmission are uncontrollable line rise (upward of 500-600 psi), high line pressure in reverse, buzzing noise, broken direct clutch drums and/or broken cases. These problems are usually caused by reverse boost oil that enters the torque signal circuit due to a wear-created cross leak at the sleeve.
HOW-TO bypass the auto transmission controls in electronic auto transmission-compatible PCMs. I have gotten a couple of questions on how I was able to bypass the auto trans controls on a stock 3800 PCM in order to prevent early rev limiters and other drivability issues it had when I was not using an electronic automatic transmission.
If you are using the 4L80E transmission, you must use the vehicle speed sensor (VSS), and the correct brake switch. These are necessary to make the transmission work correctly. The vehicle speed sensor lets the computer know how fast the wheels are turning.
The following is a list of problems and possible solutions, should your 4L80E suddenly start to give you trouble. P-R-N-D work, upshifts are erratic and occur at random engine speeds, will not upshift from first gear (no upshifts at all): This problem seems very serious in nature but in fact this is something very simple to fix.
An engine speed sensor, also known as vehicle speed sensor, retrieves and sends data to your car's computer system. A car speed sensor shows the car's The symptoms of a bad transmission speed sensor are same to some other engine problems, like bad throttle position sensor or faulty coil pack.
Got a new truck, 2005 Silverado. The "service air bag system" light is on and I had it read on the tech 2 by a friend of mine. It came up that both front sensors are bad. I did the reading online, tried the typical cleaning of the connector in the kick panels but that did not fix it. While I...