Main IndexAuto Repair Home Search Posts SEARCH
POSTS
Who's Online WHO'S
ONLINE
Log in LOG
IN







Search Auto Parts

97 Mercury Mystique overdrive problem


  Email This Post



blt
User

Feb 7, 2017, 10:08 PM

Post #1 of 13 (327 views)
97 Mercury Mystique overdrive problem Sign In

My Mercury has 68,000 miles. The transmission was serviced recently. It shifts smoothly into all gears around town and you wouldn't know there is a problem.
At highway speeds of 60+ in overdrive, it slips as the tach revs and seems to search for a gear to downshift. This happened intermittently, about 4 times on an 80 mile trip.
Could this be the transmission range sensor or some other sensor issue? No codes appear.


Discretesignals
Ultimate Carjunky / Moderator
Discretesignals profile image

Feb 8, 2017, 5:37 AM

Post #2 of 13 (305 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Was an OBD2 generic scanner used to see if there were codes? There are two parts to the engine computer, the OBD side and the manufacture side. The manufacture side is more concise, but it requires a high end scan tool to access. There may be manufacture codes stored. Someone needs to monitor TCC slip speed, PRDNL status, and other PIDs and hopefully catch what is going on.





Since we volunteer our time and knowledge, we ask for you to please follow up when a problem is resolved.


gsferraro
Enthusiast

Feb 8, 2017, 2:52 PM

Post #3 of 13 (289 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Hello,
Would you say this may be dropping from 4th to 3rd? Gary


blt
User

Feb 26, 2017, 12:02 AM

Post #4 of 13 (240 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Sorry for the slow response. Was traveling and am back.
I took it to a transmission guy and he said he couldn't diagnose properly because the engine was not running properly. Codes are triggered when this car has one little stutter at idle, but does not effect running above 1000 RPM. However he said replace the plugs wires and fuel filter before any trans work, so I said no thanks. I did change the plugs and no codes are present after several weeks. Aside from a transmission service and $100 for a non-diagnosis, I'm back to square one. It still intermittently floats back and forth between overdrive and the next gear.


blt
User

Feb 26, 2017, 12:04 AM

Post #5 of 13 (238 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Fluctuates intermittently from overdrive to the next gear and back up to overdrive.


(This post was edited by blt on Feb 26, 2017, 12:05 AM)


gsferraro
Enthusiast

Feb 26, 2017, 7:34 AM

Post #6 of 13 (228 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Hello,
This trans is a CD4E, there is no pan but there is a side cover(close to radiator) just above the side cover on the top of the trans is a switch that is attached to the linkage called the M.L.P.S (manual lever postion sensor) If this is faulty it can cause the trans to drop from 4th to 3rd, it may produce codes or it may not, you may want to look into that. Gary


blt
User

Feb 26, 2017, 8:07 PM

Post #7 of 13 (213 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Thank you Gary,
I will check your line of thought out.


gsferraro
Enthusiast

Feb 27, 2017, 3:28 AM

Post #8 of 13 (202 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Ok, sounds good, the switch has been updated, so if you do change it you will get the updated switch. If the early switch is on your car, the updated looks different


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Feb 27, 2017, 3:39 AM

Post #9 of 13 (202 views)
Re: 97 Mercury Mystique overdrive problem Sign In

BLT - Quote from post #4">I took it to a transmission guy and he said he couldn't diagnose properly because the engine was not running properly.<"


Take note of that. If the engine isn't running properly know that is has to first or trans wouldn't know "Jack" about how to shift properly. You had it at a shop so what was the problem found on why is doesn't run well?


T



blt
User

Feb 27, 2017, 11:07 AM

Post #10 of 13 (191 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Tom,
From DAY ONE this car shook (some vibration in steering wheel) at idle due to poor harmonic balancing. Ford had no answer, so I lived with it. The mechanic either misunderstood this as the "engine" was running poorly, or was just looking for more work.
I was not going to pay an additional bill to replace plugs, wires, and fuel filter as this was unnecessary. I replaced the plugs solely on the mileage, even though the gap and plug condition did not require it, and it was not missing.
My original question about the transmission range sensor (neutral safety switch) had some confirmation so I will spend the $40 and give this a shot first.


Tom Greenleaf
Ultimate Carjunky / Moderator
Tom Greenleaf profile image

Feb 27, 2017, 11:27 AM

Post #11 of 13 (187 views)
Re: 97 Mercury Mystique overdrive problem Sign In

OK - How are you sure that's it? You can frequently see those wobble and they can fall off! Game over if it does. I can't understand how you said Ford couldn't find that and strongly suggest to take care of that. OMG - so bad you feel it in steering wheel? This could be causing a host of problems up to real damage so until smooth as it should be if it can at all this is critical!


Tom



blt
User

Feb 27, 2017, 12:13 PM

Post #12 of 13 (183 views)
Re: 97 Mercury Mystique overdrive problem Sign In

Above 750 rpm the engine is absolutely smooth/no vibration transmitted thru steering wheel.
Transmission has always shifted properly without any issues until now.
Not sure TRS is it but it's in inexpensive fix and worth the gamble as I've read and seen on youtube.


blt
User

Mar 9, 2017, 1:24 AM

Post #13 of 13 (144 views)
Re: 97 Mercury Mystique overdrive problem Sign In

BINGO!!! The manual lever position sensor (neutral safety switch) was the problem.

Finally had a warm day to work outside!
It took some effort breaking the 5/16 bolts loose in a very awkward/tight space but was finished in 1 hour.

Thanks to all who responded, especially Gary who nailed it!

Brad


(This post was edited by blt on Mar 9, 2017, 1:37 AM)






  Email This Post
 
 


Feed Button




Search for (options) Privacy Sitemap

shopify
site analytics