200-4r issues

[jkey]

I have a bone stock 1986 Monte Carlo SS 305/2004-r. I've had it sitting since January and drove it yesterday for the first time since. The car runs and shifts beautifully but it has trouble even getting up to 55mph. Almost like its stuck in overdrive all the time or somthing (as dumb as that sounds its the best way i can describe it), and when i decel it jerks and bucks. I have checked the trans fluid and its fine. After drive for awhile and stopping it kindof smells like trans fluid is burning and the trans is getting really hot, though the fluid isn't brown. Is it possible that my Convertor is Locked 100% of the time? i literally no NOTHING about automatic transmissions.

Thanks in advance

 

[King_V]

Have you tried putting the car in D instead of OD? Or possibly manually upshifting and downshifting to see if the trans is shifting from one gear to another?

 

[jkey]

Have you tried putting the car in D instead of OD? Or possibly manually upshifting and downshifting to see if the trans is shifting from one gear to another?

yes and it does shift perfectly no matter which gear i'm in. I knew the whole feels like i'm stuck in overdrive thing would be confusing but that's the only way i know to describe how it feels.

I had an issue with it shifting to soon and properly adjusted the TV cable and now it shifts perfectly and kicks down perfectly. I guess the filter could be clogged? lockup not working properly? Sorry about my little knowledge about these transmission autos aren't usually what i mess with. I talked with a couple of mechanics here locally and they said it could be the lock up converting getting stuck or something but im not sure how good that info is.

 

[King_V]

Not being able to be there, I'm sort of guessing a little bit...

If the car is in Park or Neutral, and you nail the gas, does it rev readily? If not, I'd suspect a clogged fuel filter perhaps.

Another potential thing . . is it possible the rear brakes are holding? Either the parking brake release doesn't work, or wheel cylinders are seized and dragging on the rear wheels?

Eh, even though I'm sort of mystified by transmissions myself, I wish I were local and could see/hear/feel what's going on...

 

[horners85regal]

it actually sounds like what my 200 was doing when i first bought my Regal, Does it do it right away ? or after its driven for a bit ? My rad core was plugged to sh*t with calcium internally, the transmission fluid was getting too hot and it would lock the torque converter. It would bog it down, try and just unplug the vacuum switch under the hood for the torque converter lock up, or if you just rest your foot on the brake pedal enough to turn on the brake lights it should also unlock it. Maybe that will help you narrow it down. What you are describing though id say thats your issue. Transmission is overheating, locks up the converter in an effort to cool itself down. maybe time for a new rad and or external transmission cooler. hope this helps Dave

 

[jkey]

it actually sounds like what my 200 was doing when i first bought my Regal, Does it do it right away ? or after its driven for a bit ? My rad core was plugged to sh*t with calcium internally, the transmission fluid was getting too hot and it would lock the torque converter. It would bog it down, try and just unplug the vacuum switch under the hood for the torque converter lock up, or if you just rest your foot on the brake pedal enough to turn on the brake lights it should also unlock it. Maybe that will help you narrow it down. What you are describing though id say thats your issue. Transmission is overheating, locks up the converter in an effort to cool itself down. maybe time for a new rad and or external transmission cooler. hope this helps Dave

sounds VERY similar to my problem. When coasting i can tap the brake and it will stop bucking. However mine does it all the time. Where is the vacuum switch under the hood for the lock up?

Not being able to be there, I'm sort of guessing a little bit...

If the car is in Park or Neutral, and you nail the gas, does it rev readily? If not, I'd suspect a clogged fuel filter perhaps.

Another potential thing . . is it possible the rear brakes are holding? Either the parking brake release doesn't work, or wheel cylinders are seized and dragging on the rear wheels?

Eh, even though I'm sort of mystified by transmissions myself, I wish I were local and could see/hear/feel what's going on...

if its in park or neutral is revs freely and runs perfectly. i thought that too at first.

 

[MeanBuicks]

The most likely cause is that the TCC (converter clutch) solenoid is stuck which is a very common failure mode for these. Replacement is easy just requiring pan removal and then a couple of 10 mm bolts.

 

[jkey]

The most likely cause is that the TCC (converter clutch) solenoid is stuck which is a very common failure mode for these. Replacement is easy just requiring pan removal and then a couple of 10 mm bolts.

Is there a way to unplug it and see if it is stuck before replacing it? I imagine if its in the pan it wouldn't be worth the time to do that. Wasn't sure if there was an external connector somewhere outside the transmission for it.

 

[horners85regal]

on my buick its under the hood , drivers side close to the fender. i think its green wires going to it on one end and a small vacuum line on the other end. you just unplug the electrical connector on it. You can test it with vacuum pump and volt meter, but if it is working correctly and possibly tryn to prevent your transmission from cooking itself then make sure you find out why the transmission is over heating dont just run it unplugged unless like i said it is the vacuum switch itself that is faulty. I have mine on a toggle switch tied in at the brake pedal to cut the power side of it. I hate it locking up at times when i dont want it too

 

[MeanBuicks]

The most likely cause is that the TCC (converter clutch) solenoid is stuck which is a very common failure mode for these. Replacement is easy just requiring pan removal and then a couple of 10 mm bolts.

Is there a way to unplug it and see if it is stuck before replacing it? I imagine if its in the pan it wouldn't be worth the time to do that. Wasn't sure if there was an external connector somewhere outside the transmission for it.

Unplugging it electrically will not help when the solenoid fails in this manner. There is an internal check valve in the solenoid that normally bleeds a hydraulic signal off until it is commanded on electrically. What happens is that this valve sticks closed, a mechanical failure, that will exist whether it's plugged in or not. This causes the TCC to apply at all times as the transmission shifts to second gear and beyond. The internal hydraulic signal drops off on the 2-1 shift so that's why the car doesn't stall when stopped even with the solenoid stuck.