|
|
Transmission switches to lower gear on it's own!
|
|
|
| |
|
joezapp
User
Jun 22, 2015, 9:03 PM
Post #26 of 38
(869 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
That's what I thought. You could imagine my mindset when he gives me a 7AM appointment and tells me that the check is free, and then I show up and he tells me that there is nothing more to check for free other than what I already know. So do you think I should give the guy in Cedar Grove a call? I'm thinking that unless he is going to identify a specific wiring/connection issue, there may be no point in going there, and maybe I should just change the crank position sensor. What do you think? Here are the 4 causes of code 725 from the Factory Service Transmission Diagnostic Procedures Manual for this car (aside from "low battery voltage" and "intermittent code") 1) Bad connections at various connectors 2) Crank position sensor signal open 3) Crankshaft position sensor ground circuit open 4) TCM crank position sensor monitoring defective Thanks, Joe
|
|
| |
|
gsferraro
Veteran
Jun 24, 2015, 3:49 AM
Post #27 of 38
(854 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Joe, If you wanted to change that sensor yourself, it has to be adjusted correctly or the car will not run right. I have spacers that i grease on to the end of the sensor so the air gap is correct. I guess if you wanted to call cedar grove it wouldnt hurt, i had lunch with the guy back in march he seemed like an alright guy. Sometimes those sensors get stuck in the bellhosing due to corrosion, but before you pull it out and replace, i would check connections. Gary
|
|
| |
|
joezapp
User
Jun 24, 2015, 3:39 PM
Post #28 of 38
(848 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Hi Gary. I spoke with Mike. Very nice guy. His free check is the same as yours. He said that since limp mode doesn't happen until the car is driven about a half hour, he recommended that I change the crank position sensor before going crazy trying to track wiring. So you and he are in agreement there. Unfortunately, even though I have the advantage of owning the Transmission Diagnostic Manual for this car, which explicitly states which pins/connections/wiring/terminals to examine, neither I nor my mechanic really know where to look. I say unfortunate because it's probably not very hard when you already know what to look for, but not where. It also doesn't help that a lot of things on this car are not easily accessible. So I'll have my mechanic put in the sensor using the care that you describe. Keeping fingers crossed! I'll let you know when it's in. Thanks. Joe
|
|
| |
|
gsferraro
Veteran
Jun 24, 2015, 6:21 PM
Post #29 of 38
(844 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Ok, sounds good. Gary
|
|
| |
|
joezapp
User
Jul 5, 2015, 10:02 PM
Post #30 of 38
(832 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Hi Gary. I was able to put it in myself. The crank position sensor wasn't the adjustable type...just the screw and harness...so I could handle that. And you were right. It DID get stuck due to corrosion. I got it out with a long screw and a prybar. Car starts and runs. I won't know until I take it on a long drive if the problem of limp-in mode is resolved. Some observations in the meantime: The connector, all the wires leading from it, and the connectors that they lead to, all are wet with a thin coating of motor oil. I see no other issues with the connectors or wires. No breaks or frays. Also, the inside of the crank sensor connector was moist from motor oil. Additionally, I had to use a touch of liquid wrench to slide the red clip on the connector. Some got inside the connector. I turned the connector upside down and dabbed it with towels a few times. Very thin brown liquid came out, undoubtedly some motor oil mixed with liquid wrench. Only after I was all done did I think that maybe I should have taken an extra step to clean the inside of the connector further with possibly paper towel wrapped around a toothpick. While there was certainly no sludge inside the connector, there was likely still some thin oil. Do you think that I ran the risk of compromising the integrity of this job by not thinking to do that? Thanks, Joe
|
|
| |
|
gsferraro
Veteran
Jul 6, 2015, 3:35 AM
Post #31 of 38
(824 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Joe, Nice job on doing this yourself, I have always liked a clean connection, alot of issues i had with transmissions were connection problems. I like clean connections, i use a non-conductive eletric parts cleaner which is also a degreaser made by CRC, then i put di-eletric grease on the connection. Where did you purchase the part from. If the connection is hard to get to you can even spray with the cleaner and let it dry. Gary
|
|
| |
|
joezapp
User
Jul 6, 2015, 10:38 PM
Post #32 of 38
(819 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Hi Gary. I got it online. I planned on getting the Standard brand, but there was a vast difference in price between Standard and Mitsubishi, and my mechanic friend said Mitsubishi may even be better, so I went with Mitsubishi. Thanks for confirming that degreasing is proper protocol. I was planning to use brake parts cleaner, but I'll look for CRC's degreaser. I like the idea of the di-electric grease, too. I also forgot to grease the o-ring, so basically I'll be going for round 2 with this job. It's not really difficult to get to, and the second time around is generally quicker. I'll report back after a long drive to see if this resolved limp-in mode. Thanks so much...Joe
|
|
| |
|
gsferraro
Veteran
Jul 7, 2015, 4:08 PM
Post #33 of 38
(806 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Joe, Sounds good , let me know how it goes. Gary
|
|
| |
|
joezapp
User
Jul 12, 2015, 12:25 AM
Post #34 of 38
(794 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Hi Gary. I just wanted to update you. That CRC is really good stuff! Thanks for that. I cleaned the connection nicely and put on the de-electric grease. I also sprayed a contact that the wire from the crank position sensor leads to. It had a lot of oil on it. I ran the car tonight for a while, but probably just shy of the point where it would go into limp-in mode. On Monday it will be driven further, so I will know for sure on Monday night if this resolved the issue. I'll let you know. Thanks, again! Joe
|
|
| |
|
gsferraro
Veteran
Jul 12, 2015, 3:49 PM
Post #35 of 38
(786 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Joe, Yes, let me know how it goes. Gary
|
|
| |
|
joezapp
User
Jul 13, 2015, 10:10 PM
Post #36 of 38
(777 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Hi Gary. You are THE MAN. I don't think I'm jumping the gun by saying that, after changing the crank position sensor and cleaning up everything in the vicinity of it, it sure appears that limp-in mode is now a thing of the past. I took the car on that long drive tonight, and for the first time since April, it did not go into limp-in mode! Thanks so much for a) your patience, b) your detailed and informative explanations, c) knowing that my car was going into limp-in mode (my mechanics were not aware of a transmission limp-in mode), d) knowing that code 0725 had something to do with the crank position sensor and/or circuit (most people go right for the input and output sensors, which as you said, are different codes), and e) knowing that, even though the engine may be happy with the crank position sensor, the TCM may not be happy with it (my mechanics and others felt that if the car is running, the crank position sensor is not the issue). Thanks also for letting me know about Mike...a real nice guy who has a good reputation around here. I'll certainly go to him before I go to a place like Lee Myles. People like you who share your vast expertise bring joy to what could be an otherwise miserable time. No one likes car problems, especially the kind that are not routine to diagnose. You got me through it. Very appreciative for that. I hope your customers realize that they are in good hands with you. Much success to you! Thanks for everything. Thanks also to Hammer Time and Discreetsignals for their much appreciated input. Joe
|
|
| |
|
Hammer Time
Ultimate Carjunky
/ Moderator
Jul 14, 2015, 2:19 AM
Post #37 of 38
(775 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Gold stars for Gary Good Job ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ We offer help in answering questions, clarifying things or giving advice but we are not a substitute for an on-site inspection by a professional.
|
|
| |
|
gsferraro
Veteran
Jul 14, 2015, 5:51 PM
Post #38 of 38
(761 views)
|
Re: Transmission switches to lower gear on it's own!
|
Sign In
|
|
Thanks for the kind words joe, and for the gold stars, im glad you it fixed. The good thing about this is there was a code present, with a code that gives some direction in your diagnosis. Gary
|
|
| |
|