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Resolved 2g GS-T AUTO won't shift out of 1st gear...

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J Fresh

Proven Member
47
10
Feb 23, 2017
Vista, California
Vehicle: 1997 Spyder GS-T AUTO transmission. I Bought car in 2014 with 44k miles, it now has 106k. Never had any issues in the last 7 years!

Problem:
I went to go to work today and when going from Park into Reverse, it shifted or "slammed" into gear, much harder than usual. It "sounded like" someone hit a hammer on metal or something to be honest... I exited my driveway in reverse slowly and it seemed fine. I put it in Drive from Reverse (shifted normally/easily as usual unlike that weird sound I heard going from Park into reverse 30 seconds prior) and hit the accelerator only to find out that my GST WONT shift out of 1st gear! It easy goes back into Park, Reverse and Drive but just wont shift out of first gear. When I let off the gas, it coasted like it was in neutral. I had to put it back into Park then back into Drive to get it to go back into 1st gear... I drove around the block slow af and parked it in my driveway...

I’ve never had any transmission issues, slips or anything. I have not changed the trans fluid but I know all fluids were freshly swapped when I bought the car, now 7 years ago & 60k miles later… I recently swapped out the water pump/TB due to weep holes leaking. Afterwards, I got a CEL for a upstream O2 sensor. I swapped out the old sensor and reset the OBD and drove around town. I drove it for 75 miles over 3 days running errands around town, zero issues whatso ever.

Considering Ive NEVER had any transmission issues, Due to the loud/harsh shift I felt when I put it into Reverse, do you think I have a trans solenoid issue for gear 1-2? I read online that Auto trans' have solenoids for each gear and if one goes bad, due to old age, dirty trans fluid etc, it prevents the car from shifting...

I thought about changing the trans fluid and trans filter but didn’t want to drain it fully as I read that draining it 100% can lead to more slips... Plus I wanted advice from the community before I go any further as I dont have much transmission work experience under my belt. I checked the trans fluid level and its perfect. The fluid does not smell burnt and is a slight reddish color.... Thoughts?

Again, the engine runs fine, no CEL's after 76 miles of errand running & I’ve never had ANY transmissions issues, slips or anything until the other day. The issue came out of nowhere with no warning signs of wear at all. Its like a light switch to change gears went missing all of a sudden LOL …. Any advice to help is greatly appreciated! Thanks DSM fam in advance!
 
Last edited:
Solution
thank you for this. I read it when you wrote it but I never replied. I swapped the solenoids for gears 1 & 2 but the non shifting issue was still present. I was going to sell the car but a friend told me the TCU's are sometimes the culprit of shifting issues in DSM's... Got one off Ebay and to my surprise, were back to normal shifting! Still testing it out for reliability but I feel like the problem is resolved!!
The TCU is bolted flat to the floor, next to the firewall, behind the radio. It is mounted on a metal bracket. Normally you won’t need to unbolt it to unplug it, but sometimes it’s just too tight back there and unbolting it will allow you to rotate it a little which can help you unplug it.
 
You are correct that there are 4 solenoids, but they are better called:
Shift Solenoid A
Shift Solenoid B
Torque converter Lockup
Line Pressure

The shift solenoids work in tandem to control what forward gear is engaged.
A___B
on_on -- 1st
on_off -- 2nd
off_off -- 3rd
off_on -- 4th

They are controlled by the TCU supplying +12v to the solenoids.

The torque converter lockup solenoid only engages while the car is in 4th gear and at a cruising speed, typically about 5-15 seconds after hitting a steady highway speed.

The line pressure solenoid pulses to control the line pressure. The more it pulses, the lower the pressure in the transmission, and the softer it then shifts. It only drops the pressure to shift.

If the TCU detects a problem, it will go into a limp mode, where you will only have 3rd gear and full line pressure. This basically means all the solenoids are turned off.

Reverse is controlled through a manual valve, as is neutral. Park is just neutral but it engages a parking pawl.

To test the shift solenoids, you can check the resistance between the orange wire and ground and the yellow wire and ground. The line pressure solenoid can be check by checking the resistance between the blue and ground. These should have approximately 3 ohms resistance.

The torque converter lockup can be checked by checking the resistance between the red wire with the blue stripe and ground. This should have about 13 ohms resistance. Early 1g's had a lockup solenoid with 3 ohm resistance. If these are installed, it will burn a transistor right off the circuit board of the TCU. I know. My car has this issue.

None of these being bad should cause the car to want to stay in neutral. There is the possibility that they managed to break the manual valve when installing the valve body. This is easily done by not having the one piece inline before bolting the valve body in. I'm not sure if you can get that part on it's own.


If the TCU has a code stored, it can be read with a multimeter or test light.
http://www.plymouthlaser.com/tcucodes.htm
I went to go to work today and when going from Park into Reverse, it shifted or "slammed" into gear, much harder than usual. It "sounded like" someone hit a hammer on metal or something to be honest... I exited my driveway in reverse slowly and it seemed fine. I put it in Drive from Reverse (shifted normally/easily as usual unlike that weird sound I heard going from Park into reverse 30 seconds prior) and hit the accelerator only to find out that my GST WONT shift out of 1st gear! It easy goes back into Park, Reverse and Drive but just wont shift out of first gear. When I let off the gas, it coasted like it was in neutral. I had to put it back into Park then back into Drive to get it to go back into 1st gear... I drove around the block slow af and parked it in my driveway...

I’ve never had any transmission issues, slips or anything. I have not changed the trans fluid but I know all fluids were freshly swapped when I bought the car, now 7 years ago & 60k miles later… I recently swapped out the water pump/TB due to weep holes leaking. Afterwards, I got a CEL for a upstream O2 sensor. I swapped out the old sensor and reset the OBD and drove around town. I drove it for 75 miles over 3 days running errands around town, zero issues whatso ever.

Considering Ive NEVER had any transmission issues, Due to the loud/harsh shift I felt when I put it into Reverse, do you think I have a trans solenoid issue for gear 1-2?

Again, the engine runs fine, no CEL's after 76 miles of errand running & I’ve never had ANY transmissions issues, slips or anything until the other day. The issue came out of nowhere with no warning signs of wear at all. Its like a light switch to change gears went missing all of a sudden LOL …. Any advice to help is greatly appreciated! Thanks DSM fam in advance!

sounds like I need to replace the 1-2 solenoid.... correct??
 
1997 GS-T Spyder 4g63 Automatic...

Transmission Issue: Car will NOT shift out of 1st gear. Here’s what happened out of no where…

I was backing out of my driveway. when I put the car into reverse from Park, the car made a fairly loud (unusual) noise but the car shifted into “R” like normal. I backed out of the driveway and put it into Drive. When I hit the accelerator, the car drives forward but just wont shift out of 1st gear no matter how high the RPM’s go…. It acts like the shifter is in the “1” position when it is in “D”. When I let off the gas, the RPM’s drop to idle as if the car is in “N”, and the car just coasts... If I touch the gas at all after letting go, the transmission shifts back into 1st gear until I let off the gas, then it acts like it is in “N” again… Obviously, I have not done this to the vehicle many times, just enough to get enough info to describe to auto shops what the problem and symptoms are.

I also noticed that my Speedometer & RPM needles just started to fickle out on me. This happened around the time of my Trans not shifting out of 1st gear… Both gauges work 90% of the time but sometimes the Speedo & RPM gauges act like they’re possessed by ghosts and go haywire or stop working all together for a few seconds then pop back “on” – I guessing this COULD be a reason my car wont shift out of 1st gear…

I brought it to a few transmission places here in San Diego and was told they cannot service this transmission due to “Lack of parts availability” – perhaps shops just don’t want to mess with my GS-T… This issue of not shifting out of 1st gear literally came out of no where like a light switch. I’ve never had any issues with the engine OR transmission after 7 years of ownership and 50 k miles


Does anyone have any insight on what the issue "MAY" be? Does anyone live In LA/SD who can fix this issue?

Does anyone want to buy my GS-T and fix the trans yourself? This was my weekend coast cruiser with the top down.. I'd like to fix it but I'm also open to offers if anyone works on these auto transmissions themselves....


PM. for videos and pictures. Engine runs just fine and car overall is in good condition for its age but the bi*** just won't shift out of 1st gear! :(
 
Your TCU should be commanding the 12v to the solenoids for shifting. For 1st gear, it applies voltage to BOTH shift solenoids, A and B. I can't tell you why it is not turning off the B solenoid for 2nd though.
The sequence for the 2 shift solenoids in our automatics are as follows, as they are computer controlled for the shifts (except LIMP mode, in case all power to the trans fails)
1st - A on, B on
2nd - A on, B off
3rd - Both off (limp mode also)
4th - A off, B on
 
See your other post.
Both solenoids are ON in 1st gear.
Here is the shift setup from another thread.
Marty
thanks Marty > I wound up swapping the solenoids but sadly nothing changed... I was going to sell it but then heard from a friend that the TCU in these are semi known to produce shifting issues... I found one on Ebay, just swapped the TCU and we're back to normal operation. I wasn't putting too much hope into it working but it seems to be my issue! I literally just got around to this project tonight, Whoops!
 
thank you for this. I read it when you wrote it but I never replied. I swapped the solenoids for gears 1 & 2 but the non shifting issue was still present. I was going to sell the car but a friend told me the TCU's are sometimes the culprit of shifting issues in DSM's... Got one off Ebay and to my surprise, were back to normal shifting! Still testing it out for reliability but I feel like the problem is resolved!!
 
Solution
Was your TCU a MD 750092?
I have 2 spares....I went to an aftermarket transmission computer for my car because of factory TCU issues.
Glad you got it fixed! I saw that TCU on Ebay, LOL.
 
I see now it is a 2g. IDT I have any 2g TCU's but if that one ever gives you issues, you can check out ForcedFour.com for a stand alone transmission computer. :thumb:
It is what I run.
 
thank you for this. I read it when you wrote it but I never replied. I swapped the solenoids for gears 1 & 2 but the non shifting issue was still present. I was going to sell the car but a friend told me the TCU's are sometimes the culprit of shifting issues in DSM's... Got one off Ebay and to my surprise, were back to normal shifting! Still testing it out for reliability but I feel like the problem is resolved!!
I am about to purchase a super clean 98 Eclipse GS Spyder Automatic. Owner says it is stuck in first gear. Did this TCU swap continue to fix the issue?
 
He was last seen on here in October but when he changed his TCU (they are just like our ECU's, the capacitors get old and leak and no longer function). When he just put a different one in, it fixed his issue.
Read thru the thread and do any tests that were suggested to see if yours acts the same as his did.
 
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