deeswalker Posted March 23, 2014 Share Posted March 23, 2014 This is happening on my 1990 Comanche. I recently changed the fluid and filter about a month or so ago. I checked the two connectors by the Trans dip stick and the connectors on the TCU and fuse all looked good. This started happening at highway speeds of 65-75 MPH and then started happening at lower speeds of 25-30 MPH. I can shift out of D into 3 and back and everything seems fine. Has anybody ever had this problem? HELP! Link to comment Share on other sites More sharing options...
MuddFoot Posted March 23, 2014 Share Posted March 23, 2014 check tps first Link to comment Share on other sites More sharing options...
Dillithium Posted March 23, 2014 Share Posted March 23, 2014 How old was the fluid that came out? Link to comment Share on other sites More sharing options...
deeswalker Posted March 23, 2014 Author Share Posted March 23, 2014 I havent checked the tps, should i check it for adjustment and remove it and clean it? I do not know when the fluid was changed prior to me changing it. Okay found the information on how to adjust it from here http://comancheclub.com/topic/36382-cruisers-renix-tips/ or search for Cruisers renix tips. Got to go and check this out soon. And, Thank you both, will post my results later. Link to comment Share on other sites More sharing options...
Dillithium Posted March 23, 2014 Share Posted March 23, 2014 I've read that when replacing transmission fluid, if it's been in there for a long time the sudden pressure difference due to the new fluid can cause it to act up. I hope that's not the case, but you mentioned changing the fluid recently which triggered that connection for me. Link to comment Share on other sites More sharing options...
deeswalker Posted March 23, 2014 Author Share Posted March 23, 2014 Okay, I checked the voltages on the TPS and between "A" and "D" I got 4.71 volts (Reference Voltage) and between "B" and "D" I got 4.04 volts (Output Voltage). Using the formula 4.71 volts X 83% or .83 = 3.9093 volts a difference of 0.1307 volts. That would be 4.04 volts minus 3.9093 volts = 0.1307 volts. Should the output voltage be closer to the calculated voltage of 3.9093? Is this enough of a difference to cause the transmission to act up like it is? And should I replace the TPS? The problem seems to be getting worse lost D and 3 limped home half a block, good thing i was close. Link to comment Share on other sites More sharing options...
deeswalker Posted March 25, 2014 Author Share Posted March 25, 2014 Bump I really need help. Link to comment Share on other sites More sharing options...
88whitemanche Posted March 25, 2014 Share Posted March 25, 2014 Have you tried readjusting the tps to spec to have the correct reading? If not buy a tps (they are fair priced) and install it to see what happens Link to comment Share on other sites More sharing options...
ParadiseMJ Posted March 25, 2014 Share Posted March 25, 2014 I've read that when replacing transmission fluid, if it's been in there for a long time the sudden pressure difference due to the new fluid can cause it to act up. I hope that's not the case, but you mentioned changing the fluid recently which triggered that connection for me. No, what you read has to do with pressure flushing the transmission. The AW4 is NOT that sensitive. Check your fluid level and condition again, you might want to do a drain and fill again, especially if the fluid was brown-ish. There are ~8 qts. total in the AW4, most of which are captive in the torque converter. Drain and fill a series of 3 to get the majority of the old fluid out and new fluid in. 3.75 qts out, 3.75 qts. back in. Link to comment Share on other sites More sharing options...
gogmorgo Posted March 25, 2014 Share Posted March 25, 2014 Did you put the same amount of fluid in as you took out, or did you just go by the dipstick? If you did, sometimes it takes a bit for the atf to work itself into around, so it may not be as full as it once was. Check to make sure it's full with the engine running, after driving. Make sure you're looking at the right side of the dipstick, one's for cld, the other for hot. Also, Jeep die-hards say to use Dexron-III, despite Chrysler currently recommending ATF+4, but I don't know what you're running. That's not a debate I really want to get into, but I can say that the two probably shouldn't be mixed. Something else that's quick, easy, free, and can't hurt anything if it's not the issue: http://www.allpar.com/SUVs/jeep/cherokee-transmission.html I've been dealing with similar symptoms with my aw4, but my issues are caused by low fluid. Just changed out my cooler line connectors which stopped the total-loss atf lubrication of the cat. Have you tried unplugging your tranny computer and shifting manually? Link to comment Share on other sites More sharing options...
Dillithium Posted March 25, 2014 Share Posted March 25, 2014 I've read that when replacing transmission fluid, if it's been in there for a long time the sudden pressure difference due to the new fluid can cause it to act up. I hope that's not the case, but you mentioned changing the fluid recently which triggered that connection for me. No, what you read has to do with pressure flushing the transmission. The AW4 is NOT that sensitive. Check your fluid level and condition again, you might want to do a drain and fill again, especially if the fluid was brown-ish. There are ~8 qts. total in the AW4, most of which are captive in the torque converter. Drain and fill a series of 3 to get the majority of the old fluid out and new fluid in. 3.75 qts out, 3.75 qts. back in. My mistake, I remembered it incorrectly. Link to comment Share on other sites More sharing options...
deeswalker Posted March 25, 2014 Author Share Posted March 25, 2014 Did you put the same amount of fluid in as you took out, or did you just go by the dipstick? If you did, sometimes it takes a bit for the atf to work itself into around, so it may not be as full as it once was. Check to make sure it's full with the engine running, after driving. Make sure you're looking at the right side of the dipstick, one's for cld, the other for hot. Also, Jeep die-hards say to use Dexron-III, despite Chrysler currently recommending ATF+4, but I don't know what you're running. That's not a debate I really want to get into, but I can say that the two probably shouldn't be mixed. Something else that's quick, easy, free, and can't hurt anything if it's not the issue: http://www.allpar.com/SUVs/jeep/cherokee-transmission.html I've been dealing with similar symptoms with my aw4, but my issues are caused by low fluid. Just changed out my cooler line connectors which stopped the total-loss atf lubrication of the cat. Have you tried unplugging your tranny computer and shifting manually? I am using Dextron lll mercon ATF and i filled it using the dip stick. To me the fluid level seems fine. I will try draining 3 and adding three to see if it changes anything. I just purchased a new TPS and set it up with my reference voltage of 4.72 and using the formula 4.72 X 83% or 0.83 set the output voltage to 3.91 volts took it for a drive and it did it a little at first and that was it. I took it out and opened it up and the drove slowly back into the neighborhood didn't seem to act up. Will let you all know if it does when i take it out on the freeway. Link to comment Share on other sites More sharing options...
deeswalker Posted March 25, 2014 Author Share Posted March 25, 2014 Thank you all that are trying to help me with this, you have been a tremendous help. Link to comment Share on other sites More sharing options...
deeswalker Posted March 28, 2014 Author Share Posted March 28, 2014 I've read that when replacing transmission fluid, if it's been in there for a long time the sudden pressure difference due to the new fluid can cause it to act up. I hope that's not the case, but you mentioned changing the fluid recently which triggered that connection for me. No, what you read has to do with pressure flushing the transmission. The AW4 is NOT that sensitive. Check your fluid level and condition again, you might want to do a drain and fill again, especially if the fluid was brown-ish. There are ~8 qts. total in the AW4, most of which are captive in the torque converter. Drain and fill a series of 3 to get the majority of the old fluid out and new fluid in. 3.75 qts out, 3.75 qts. back in. I have started to add a little more fluid to the transmission, like a half a quart so far. I will monitor the level to see what happens. What I am hoping to see is the fluid level drop after the system burps a little air out. So far after driving it on short runs the problem hasn't returned. Link to comment Share on other sites More sharing options...
deeswalker Posted March 31, 2014 Author Share Posted March 31, 2014 Now the transmission is shifting at the wrong time, sometimes to soon, sometimes to late, but not all the time. Sometimes it will not give me any problems at all. Link to comment Share on other sites More sharing options...
gogmorgo Posted March 31, 2014 Share Posted March 31, 2014 Did you adjust the kick-down cable following the instructions in the link I posted? It only takes a few seconds and requires zero tools. Link to comment Share on other sites More sharing options...
deeswalker Posted March 31, 2014 Author Share Posted March 31, 2014 Did you adjust the kick-down cable following the instructions in the link I posted? It only takes a few seconds and requires zero tools. To be honest, I completely forgot about this, thinking I will do this when I get back under the hood. This just might be the fix. Thanks Pete Will let you know what happens. Link to comment Share on other sites More sharing options...
deeswalker Posted April 2, 2014 Author Share Posted April 2, 2014 Kick down adjusted as per your recommendation. It did change shifting points or when it shifts, and it seems to shift sooner than it did. It now seems to shift back and fourth between gears at different speeds. It will downshift and then upshift at odd intervals. Link to comment Share on other sites More sharing options...
gogmorgo Posted April 2, 2014 Share Posted April 2, 2014 Not sure what you mean by that. If it changed anything, it would have been because it was out of adjustment before, and your shift points will change to what they should be as a result of the proper adjustment. You may also be noticing differences in where the torque converter locks/unlocks. Did it do anything other than change the shift points? What exactly is your issue, now? Does it shift normally when accelerating or decelerating? Is it downshifting normally under brisk acceleration? Does it stay in the same gear at constant speeds? Does it stay in gear at all? If it's just popping back and forth between gears at ~30mph in traffic, I think that's just because it's bouncing off the bottom end of what 4th gear can do. Mine does that too. A little slower and it stays in 3rd, a little faster it stays in 4th. Link to comment Share on other sites More sharing options...
cruiser54 Posted April 2, 2014 Share Posted April 2, 2014 Trans switch in Power or comfort mode? Does it light up in Power mode? Also, there is a switch up near the top of the brake pedal. White with a pin sticking out the middle and resting on the pedal. You should not be able to see the pin unless the brake pedal is depressed. The switch is easily adjusted. The switch unlocks the torque converter whenever the brake pedal is depressed. Could a maladjusted switch, along with a wiggly pedal be an issue? Takes 2 minutes to check and adjust. Link to comment Share on other sites More sharing options...
deeswalker Posted April 2, 2014 Author Share Posted April 2, 2014 Trans switch in Power or comfort mode? Does it light up in Power mode? Also, there is a switch up near the top of the brake pedal. White with a pin sticking out the middle and resting on the pedal. You should not be able to see the pin unless the brake pedal is depressed. The switch is easily adjusted. The switch unlocks the torque converter whenever the brake pedal is depressed. Could a maladjusted switch, along with a wiggly pedal be an issue? Takes 2 minutes to check and adjust. I will take a look at that switch as soon as I can. It does it in power and comfort. And the light functions. Link to comment Share on other sites More sharing options...
deeswalker Posted April 2, 2014 Author Share Posted April 2, 2014 Trans switch in Power or comfort mode? Does it light up in Power mode? Also, there is a switch up near the top of the brake pedal. White with a pin sticking out the middle and resting on the pedal. You should not be able to see the pin unless the brake pedal is depressed. The switch is easily adjusted. The switch unlocks the torque converter whenever the brake pedal is depressed. Could a maladjusted switch, along with a wiggly pedal be an issue? Takes 2 minutes to check and adjust. It does this in both power and comfort modes. The light works in power mode. I will check the switch in the morning. Thank you for the suggestion. Link to comment Share on other sites More sharing options...
deeswalker Posted April 2, 2014 Author Share Posted April 2, 2014 Not sure what you mean by that. If it changed anything, it would have been because it was out of adjustment before, and your shift points will change to what they should be as a result of the proper adjustment. You may also be noticing differences in where the torque converter locks/unlocks. Did it do anything other than change the shift points? What exactly is your issue, now? Does it shift normally when accelerating or decelerating? Is it downshifting normally under brisk acceleration? Does it stay in the same gear at constant speeds? Does it stay in gear at all? If it's just popping back and forth between gears at ~30mph in traffic, I think that's just because it's bouncing off the bottom end of what 4th gear can do. Mine does that too. A little slower and it stays in 3rd, a little faster it stays in 4th. If it changed anything, it would have been because it was out of adjustment before, and your shift points will change to what they should be as a result of the proper adjustment. You may also be noticing differences in where the torque converter locks/unlocks. Did it do anything other than change the shift points? It just seems to shift more frequently durning acceleration. What exactly is your issue, now? Does it shift normally when accelerating or decelerating? Is it downshifting normally under brisk acceleration? Does it stay in the same gear at constant speeds? Does it stay in gear at all? It is staying in gear now but it is nothing like it was prior to the dropping out of gear problem. Not the same truck. If it's just popping back and forth between gears at ~30mph in traffic, I think that's just because it's bouncing off the bottom end of what 4th gear can do. Mine does that too. A little slower and it stays in 3rd, a little faster it stays in 4th. Can the kickdown be fine tunened until the function improves? Link to comment Share on other sites More sharing options...
gogmorgo Posted April 3, 2014 Share Posted April 3, 2014 By more frequently, do you mean it's shifting all the way up into 4th as quickly as it can, or shifting back and forth between gears? If your torque converter is locking/unlocking repeatedly at random, it could seem like your truck is shifting up and down, as well. We don't know what the truck was like before, and we don't know what the truck is like now... It should kick down almost immediately when you go to around 3/4 throttle, maybe twice if you push it down most of the way to the floor. Cruiser has far more experience than I do. He may be onto something. I didn't even know that brake pedal switch existed. Also, the power light is only controlled by the switch position. You can unplug the shift computer and the light will still come on. In power mode, however, it should be shifting at a noticeably higher rpm and kicking down sooner, around 2500rpm and 1/2 throttle, iirc. Link to comment Share on other sites More sharing options...
deeswalker Posted April 3, 2014 Author Share Posted April 3, 2014 By more frequently, do you mean it's shifting all the way up into 4th as quickly as it can, or shifting back and forth between gears? If your torque converter is locking/unlocking repeatedly at random, it could seem like your truck is shifting up and down, as well. We don't know what the truck was like before, and we don't know what the truck is like now... It should kick down almost immediately when you go to around 3/4 throttle, maybe twice if you push it down most of the way to the floor. Cruiser has far more experience than I do. He may be onto something. I didn't even know that brake pedal switch existed. Also, the power light is only controlled by the switch position. You can unplug the shift computer and the light will still come on. In power mode, however, it should be shifting at a noticeably higher rpm and kicking down sooner, around 2500rpm and 1/2 throttle, IIRC. I mean it shifts all the way up into 4th normally, and drops into 3rd and back into 4th and drops into 3rd and back into 4th. I does not do this all the time, it is an intermittent problem. As far as the break pedal switch is concerned, I will look into that in the morning. Again thank you all for your suggestions. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now