91 Coupe Auto Trans Problem
Thread Starter
Cruising
Joined: Jul 2015
Posts: 12
Likes: 0
From: Englewood Florida
91 Coupe Auto Trans Problem
Hey Everyone, I have searched the web and this forum but can't find qthe answer. First, how can I tell what auto tranny I have? I have checked the door labels, nothing about the tranny there.
Anyway here is the main problem. I just bought this car, which had sat in a garage stored for at least a couple of years neglected,and just got it back from the shop doing some other work. I did have the trans fluid flushed at the shop. I drove it all day Sat and put about 100 miles driving all kind of conditions. Ran great no issues. Drove it around Sun for about 50 miles or so and again ran great. I woke up this morning, went out to go drive it to work and it is stuck in second gear. Now she will go from park to reverse, all good. shift to nuetral all good. Sift to drive and wont come out of second. If i manually down shift all the way to first, it will drop into first gear. when I shift to second it shifts to second. Shift to third stays in second.
Anybody got any ideas?
Thanks
Anyway here is the main problem. I just bought this car, which had sat in a garage stored for at least a couple of years neglected,and just got it back from the shop doing some other work. I did have the trans fluid flushed at the shop. I drove it all day Sat and put about 100 miles driving all kind of conditions. Ran great no issues. Drove it around Sun for about 50 miles or so and again ran great. I woke up this morning, went out to go drive it to work and it is stuck in second gear. Now she will go from park to reverse, all good. shift to nuetral all good. Sift to drive and wont come out of second. If i manually down shift all the way to first, it will drop into first gear. when I shift to second it shifts to second. Shift to third stays in second.
Anybody got any ideas?
Thanks
Safety Car
Joined: Aug 2009
Posts: 3,751
Likes: 275
From: Melbourne, Victoria, Australia
Hey Everyone, I have searched the web and this forum but can't find qthe answer. First, how can I tell what auto tranny I have? I have checked the door labels, nothing about the tranny there.
Anyway here is the main problem. I just bought this car, which had sat in a garage stored for at least a couple of years neglected,and just got it back from the shop doing some other work. I did have the trans fluid flushed at the shop. I drove it all day Sat and put about 100 miles driving all kind of conditions. Ran great no issues. Drove it around Sun for about 50 miles or so and again ran great. I woke up this morning, went out to go drive it to work and it is stuck in second gear. Now she will go from park to reverse, all good. shift to nuetral all good. Sift to drive and wont come out of second. If i manually down shift all the way to first, it will drop into first gear. when I shift to second it shifts to second. Shift to third stays in second.
Anybody got any ideas?
Thanks
Anyway here is the main problem. I just bought this car, which had sat in a garage stored for at least a couple of years neglected,and just got it back from the shop doing some other work. I did have the trans fluid flushed at the shop. I drove it all day Sat and put about 100 miles driving all kind of conditions. Ran great no issues. Drove it around Sun for about 50 miles or so and again ran great. I woke up this morning, went out to go drive it to work and it is stuck in second gear. Now she will go from park to reverse, all good. shift to nuetral all good. Sift to drive and wont come out of second. If i manually down shift all the way to first, it will drop into first gear. when I shift to second it shifts to second. Shift to third stays in second.
Anybody got any ideas?
Thanks
You have a Turbo 700 R4 transmission, i would check the fluid level and TV cable. (the cable from trans to throttle body, it should have no play when fully open) The TV cable will adjust the trans pressure, smooth shifts with part throttle and firm shifts at full throttle.
Check the trans fluid level hot idling in park, my transmission had that symptom of only second gear and no overdrive when she died. That is the same for a couple of the 4 or 5 transmissions, i have been through over the 20 years i have had my C4.
The governor usually locks out all gears except first when its faulty, so unlikely it is the governor.
Take her to a auto trans shop for their oppinion, they are best equiped to daignose the transmission.
Good luck
Thread Starter
Cruising
Joined: Jul 2015
Posts: 12
Likes: 0
From: Englewood Florida
Thanks ghoastrider1 and gerardvg for your help. I checked the TV cable and it "seems" adjusted properly. Checked the fluid and it was low by abut 1 1/2 qts. Put new fluid in it and for about 2 blocks seemed ok then started the same BS. Because of how long she probably sat am thinking about changing the modulator valve and filter, and seeing where that gets me. She is not leaking on the driveway at all and think she may be blowing out the engine due to a bad modulator valve. Possibly the filter is so clogged from sitting.... ???? The 2 days I drove it I just didn't "feel" like a mechanical tranny issue. Maybe I am naive, (I've been wrenchin on cars since I was 9 years old, am 52 now)but it seems like an aux component (hopefully) as opposed to a pooched tranny. Any thoughts and comments are welcome.
Thanks again
GGattorr
Thanks again
GGattorr
Advanced
Joined: Oct 2014
Posts: 94
Likes: 10
From: Tampa
Your problem most likely is dirt in the valve body.
Byproduct of flushing is that new fluid scrubs out the trans, and deposits debris where it isn't useful.
Disassemble the valve body(s) spitshine completely clean with carb cleaner, and reassemble, verifying smooth movement (and return) of each valve. Other than time, you are only looking at about $15 worth of gaskets, and 5 qts of fluid.
Byproduct of flushing is that new fluid scrubs out the trans, and deposits debris where it isn't useful.
Disassemble the valve body(s) spitshine completely clean with carb cleaner, and reassemble, verifying smooth movement (and return) of each valve. Other than time, you are only looking at about $15 worth of gaskets, and 5 qts of fluid.
Race Director
Joined: Oct 2011
Posts: 16,087
Likes: 819
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
Hi
You have a Turbo 700 R4 transmission, i would check the fluid level and TV cable. (the cable from trans to throttle body, it should have no play when fully open) The TV cable will adjust the trans pressure, smooth shifts with part throttle and firm shifts at full throttle.
Check the trans fluid level hot idling in park, my transmission had that symptom of only second gear and no overdrive when she died. That is the same for a couple of the 4 or 5 transmissions, i have been through over the 20 years i have had my C4.
The governor usually locks out all gears except first when its faulty, so unlikely it is the governor.
Take her to a auto trans shop for their oppinion, they are best equiped to daignose the transmission.
Good luck
You have a Turbo 700 R4 transmission, i would check the fluid level and TV cable. (the cable from trans to throttle body, it should have no play when fully open) The TV cable will adjust the trans pressure, smooth shifts with part throttle and firm shifts at full throttle.
Check the trans fluid level hot idling in park, my transmission had that symptom of only second gear and no overdrive when she died. That is the same for a couple of the 4 or 5 transmissions, i have been through over the 20 years i have had my C4.
The governor usually locks out all gears except first when its faulty, so unlikely it is the governor.
Take her to a auto trans shop for their oppinion, they are best equiped to daignose the transmission.
Good luck
Thread Starter
Cruising
Joined: Jul 2015
Posts: 12
Likes: 0
From: Englewood Florida
Thanks again everyone. Saturday I am going to pull the pan and check the valve body and the TV valve. etc. Also gonna check the governor gear etc. If that ain't it off to the tranny shop she goes to get a total rebuild. Gotta quote from a tranny guy I now locally with a great rep for doing right the first tine. $1500 smackaroos. Not what I was wanting but what the hell, you only live once, and I so want to get this baby on the road.
I'l keep ya all posted.
I'l keep ya all posted.
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