Kirk55 Posted October 22, 2018 Share Posted October 22, 2018 Hi, i have a 2014 MKZ AWD 3.7l V6. Issue--after driving 30km the car starts to surge similar to a misfire but is consistent. Not random. Message says "AWD disabled" then after 5km it turns back on. But while it is disabled there is a slight sound like wrrrrr, wrrrr, wrrrr. Could this be AWD over heating? Or just a sensor faulty. No check engine light. 0 Quote Link to comment Share on other sites More sharing options...
bangster Posted October 22, 2018 Share Posted October 22, 2018 Is the "wrench" powertrain fault light also illuminated when it does this? The message "AWD Temporarily Disabled" is to protect it from overheating, yes. Do you have a matched set of tires on all four corners? I don't think slight wear differences matter, but I guess it could. Usually if it is disabled for significant tire size difference (using the temporary spare, for example) it would say "AWD Off". If it was the AWD light and the ETC light and message was "AWD Malfunction Service Required" then it would be more likely a bigger issue. 0 Quote Link to comment Share on other sites More sharing options...
bangster Posted October 22, 2018 Share Posted October 22, 2018 Besides a 2012 Fusion Sport/MKZ I also entertained the 2013+ MKZ with the 3.7, but never found any in my price range that were not beat up. I looked at and drove a 2013 with a new long block from Ford and it showed AWD issues, I felt it might be the tires, but it had so many other things wrong I did a little investigating but eventually passed on it as unreliable. 0 Quote Link to comment Share on other sites More sharing options...
Kirk55 Posted October 22, 2018 Author Share Posted October 22, 2018 No wrench, no check engine, 4 tires in excellent condition and same make model tires, only happens on highway, not city. And after 30 or 40km driving at highway speeds. No codes either. Its definatley annoying as the car surges or stumbles while driving. Very noticeable. 0 Quote Link to comment Share on other sites More sharing options...
bangster Posted October 22, 2018 Share Posted October 22, 2018 The MKZ doesn't show a visualization of the power transfer like some Escapes do, but I am assuming that something is causing it to always be engaged at high speeds and causing it to overheat. Sounds tedious but checking the pressure in all tires and the circumference of all the tires to see if that is what is causing it. Other things that might would be ABS sensor, but that would also throw an ABS/brake fault. I don't know of a PID or parameter you could log or watch to see the split or if power is being directed all the time to rear. 0 Quote Link to comment Share on other sites More sharing options...
drolds1 Posted October 22, 2018 Share Posted October 22, 2018 See my reply on the MKZ forum. 0 Quote Link to comment Share on other sites More sharing options...
bangster Posted October 22, 2018 Share Posted October 22, 2018 Even with the 2014 3.7 MKZ, isn't the "Transfer Case"/"PTU" just a splitter that always sends the same speed to the back as it does to the front wheels, and all the magic is in the rear end? I assume that no amount of disabling the rear clutch setup to disable AWD would help the PTU and it always spins, and other than a little more drag it still spins. I tried logging on the car I test drove (I found some PIDs to custom add) and it didn't work, I will try them and some others I added with my 2012, but there is one that shows on/off and one that shows duty (0-100%), but my hopes are not high, seem to be los of variations with them. 0 Quote Link to comment Share on other sites More sharing options...
Kirk55 Posted October 22, 2018 Author Share Posted October 22, 2018 Going to check if the PTU is leaking. That might possibly cause an overheat? 0 Quote Link to comment Share on other sites More sharing options...
bangster Posted October 22, 2018 Share Posted October 22, 2018 Does it really have a temperature sensor in the PTU and/or rear diff/clutch pack, or does it just assume that with it doing that duration of high percentage of AWD to the rear that it could overheat and it protects that way? Yes, I have more questions than answers...I only have a little experience with AWD FF/MKZ but want to know more, for when I have issues 0 Quote Link to comment Share on other sites More sharing options...
Kirk55 Posted October 22, 2018 Author Share Posted October 22, 2018 I am not sure if it does or not have a temp. Most likely yes as it has displayed a message of over heating the awd it appeared once but not since. 0 Quote Link to comment Share on other sites More sharing options...
bbf2530 Posted October 23, 2018 Share Posted October 23, 2018 Hi Kirk. In addition to the assistance you are receiving above, are you aware that your Lincoln has a 6 year/70,000 mile Powertrain Warranty? If you are still within those limits, I would recommend setting up an appointment with your Dealer's Service Department to let them diagnose the issue and repair it under warranty. Keep us updated and good luck. 0 Quote Link to comment Share on other sites More sharing options...
drolds1 Posted October 23, 2018 Share Posted October 23, 2018 11 hours ago, bangster said: Does it really have a temperature sensor in the PTU and/or rear diff/clutch pack, or does it just assume that with it doing that duration of high percentage of AWD to the rear that it could overheat and it protects that way? Yes, I have more questions than answers...I only have a little experience with AWD FF/MKZ but want to know more, for when I have issues Yes, there's a temp sensor in the PTU. Quote The serviceability of the Power Transfer Unit (PTU) is limited to the input shaft seal LH (left-hand) , input shaft seal RH (right-hand) , intermediate shaft seal, transfer case rear seal, cover seal, face seal, vent hose, temperature sensor and the output flange deflector. If any internal damage is present the Power Transfer Unit (PTU) must be replaced as a sealed unit. 0 Quote Link to comment Share on other sites More sharing options...
bangster Posted October 29, 2018 Share Posted October 29, 2018 Except for the cooled ones in some Mazdas and Fords, I don't think the PTU has any sort or sensors or controllers, even the ones used by some cars with the 6F50 (which I am sure the 3.7 powered car gets instead of the 6F35). I don't think it knows it is overheating, it just knows that whatever conditions it just had to face could cause it to overheat, so it disables it, doesn't actually have any sort of sensor that measured temperature. Something is making it think it is always at a high percentage on engaged until it figures it will overheat if it continues. That is why I logged ABS speed sensors below to see how much variance I could see. I was able to add some custom PIDs to Torque and get a couple of AWD data points for my 2012, I don't know what works for the 2014. I even data logged all 4 ABS sensors to get speeds to compare amongst the other ones and the PCM speed and GPS speed. Pretty interesting. AWD on or off really worked, only when stopped or decelerating does it go to zero along with the PWM signal. You can see when I am slowing down, AWD is off, otherwise, you can tell when I really get on it (no rain, snow, gravel, or turning off of TC) and you can see some of the abs speed sensors have different speeds that the others and the PCM speed, likely turning corners. 0 Quote Link to comment Share on other sites More sharing options...
Kirk55 Posted October 29, 2018 Author Share Posted October 29, 2018 So update: Tech noticed current PTU is from a wrecker. Also, while it was up i saw there was fluid around the casing. Might have been leaking. Tech filled PTU with 75 140 oil. Went the next day and went for 100km drive and no message or issue. Have to wait to go for another drive, but so far no issue. May have been a low oil in PTU. 0 Quote Link to comment Share on other sites More sharing options...
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