DieselAdict
If I Had The $ I Would...
- Joined
- Apr 8, 2015
- Messages
- 31
This all began about a month ago. A very minor hesitation, or so I thought, of the transmission going into gear. Progressively getting worse I realized that it was starting in 3rd gear. It began to lock up and try to shift into overdrive at about 5-10mph. The was then parked to save transmission components. The only way to drive it was manually starting in 1st and shifting though the gears. Once in OD and locked up I was able to drive it home. I started with tracing all the possible culprits. Tapped into the harness and tested the overdrive and lockup solenoid. Came out to be bad and so it was. No Fix.
I then Pulled the whole wiring harness on top of the motor and went through it. Checking for shorts and bad connections. Found a few questionable things but had no apparent problems. Fixed them properly anyways. In the end no fix.
Continued down the line checking the codes after I replaced the Solenoid. The only code that was not normal was the P0720 Output Speed Sensor Intermittent. Replaced it. No Fix
I followed through testing all the sensors and solenoids one at a time in the transmission. In which all ended up reading like the where bad. Replaced the Governor transducer and solenoid. No Fix
So now up the chain the pcm. Started testing other things such as the throttle position sensor. Readings came out correct on the sensor when I checked the resistance. Checked the input voltage and found that it was only seeing .7 volts. I traced it to the pcm and found no shorts. So now just one more thing pointing at the pcm.
I broke down and purchased one from a local guy in Bloomington Indiana that rebuilds them. This pcm was originally off of a manual and then converted to auto by the guy I bought it off of. It Fixed A LOT But!
At first I thought it was a done deal. I was able to drive the truck again. Checked a lot of voltages and the where correct such as at the supply voltage for the tps. Now at a solid 5 Volts. The only thing I noticed was when I tap on the brakes it should kick out of overdrive, it didn't. I don't know for certain if this was a problem before as the computer farther went down hill, but did work before all of this started. To add to it, it is hunting at the slightest throttle movement in and out of lock up. I have no idea if any of these to problems are related. I have checked the tps and its good brake light switch good. Even traced the wiring and checked it to the pcm all fine. I'm to the point where I am assuming that it is related.
After a solid day of driving around town and out to the farm it happened again after sitting for a couple of hours. Tried to start in 3rd gear again. No trying and shift into OD and lock up at all though.
I have been able to drive the truck despite the problem. Here is the kicker it only happens maybe 1 in 4 times the truck drove. If the problem arises I can shut the truck off and It starts fine.
Today I rechecked the codes as I should have done a week ago. Still getting the P0720 for the Output speed sensor. Ok so I completely replace the wiring not including the connectors. It Did nothing. I am going to check the codes again tomorrow see if i got rid of the p0720.
So what I really need is some insight on where to look next. Could this still be a pcm problem? I have spent countless hours and hundreds of dollars trying to figure this one out. I consider myself well versed when it comes to most automotive and electrical problems, but I am need of a guru that has been here before. Please Help
I then Pulled the whole wiring harness on top of the motor and went through it. Checking for shorts and bad connections. Found a few questionable things but had no apparent problems. Fixed them properly anyways. In the end no fix.
Continued down the line checking the codes after I replaced the Solenoid. The only code that was not normal was the P0720 Output Speed Sensor Intermittent. Replaced it. No Fix
I followed through testing all the sensors and solenoids one at a time in the transmission. In which all ended up reading like the where bad. Replaced the Governor transducer and solenoid. No Fix
So now up the chain the pcm. Started testing other things such as the throttle position sensor. Readings came out correct on the sensor when I checked the resistance. Checked the input voltage and found that it was only seeing .7 volts. I traced it to the pcm and found no shorts. So now just one more thing pointing at the pcm.
I broke down and purchased one from a local guy in Bloomington Indiana that rebuilds them. This pcm was originally off of a manual and then converted to auto by the guy I bought it off of. It Fixed A LOT But!
At first I thought it was a done deal. I was able to drive the truck again. Checked a lot of voltages and the where correct such as at the supply voltage for the tps. Now at a solid 5 Volts. The only thing I noticed was when I tap on the brakes it should kick out of overdrive, it didn't. I don't know for certain if this was a problem before as the computer farther went down hill, but did work before all of this started. To add to it, it is hunting at the slightest throttle movement in and out of lock up. I have no idea if any of these to problems are related. I have checked the tps and its good brake light switch good. Even traced the wiring and checked it to the pcm all fine. I'm to the point where I am assuming that it is related.
After a solid day of driving around town and out to the farm it happened again after sitting for a couple of hours. Tried to start in 3rd gear again. No trying and shift into OD and lock up at all though.
I have been able to drive the truck despite the problem. Here is the kicker it only happens maybe 1 in 4 times the truck drove. If the problem arises I can shut the truck off and It starts fine.
Today I rechecked the codes as I should have done a week ago. Still getting the P0720 for the Output speed sensor. Ok so I completely replace the wiring not including the connectors. It Did nothing. I am going to check the codes again tomorrow see if i got rid of the p0720.
So what I really need is some insight on where to look next. Could this still be a pcm problem? I have spent countless hours and hundreds of dollars trying to figure this one out. I consider myself well versed when it comes to most automotive and electrical problems, but I am need of a guru that has been here before. Please Help