Is is possible that my transmission governor is going bad?
06-14-2007, 01:29 PM
#1
Team Owner
Thread Starter
Is is possible that my transmission governor is going bad?
I do have a few issues with the tranny in my '92..
The first issue was a while ago when the tranny refused to shift into 3rd gear (it eventually shifted after 2 seconds on the rev limiter).
After that run, everything seemed normal again..
Went racing again last weekend and the car ran good for 4 runs and then it started acting weird again.. The transmission now shifted way too early (like at 3000 RPM)..
On the way back home from the track, the transmission was acting normal again.
Yesterday, I just drove 2 miles to the supermarket and the transmission would only shift at about 4000 rpm at PART throttle (with my foot barely on the gas).
I wouldn't even get into overdrive on the way to the super market..
When I left the supermarket to drive home, the transmission acted normal again... It's very weird.. The problem doesn't persist but it always comes back in one way or another.. I suspect a problem with the governor.. Could there be another problem?
I also have another problem with the tranny that really doesn't bother me too much but I'm sure that something isn't right.. The transmission locks up normally but sometimes, when I accelerate (with less than 30% throttle), the car vibrates a lot (sometimes for a few seconds) when the converter is unlocking..
Any input on those problems is appreciated!
The first issue was a while ago when the tranny refused to shift into 3rd gear (it eventually shifted after 2 seconds on the rev limiter).
After that run, everything seemed normal again..
Went racing again last weekend and the car ran good for 4 runs and then it started acting weird again.. The transmission now shifted way too early (like at 3000 RPM)..
On the way back home from the track, the transmission was acting normal again.
Yesterday, I just drove 2 miles to the supermarket and the transmission would only shift at about 4000 rpm at PART throttle (with my foot barely on the gas).
I wouldn't even get into overdrive on the way to the super market..
When I left the supermarket to drive home, the transmission acted normal again... It's very weird.. The problem doesn't persist but it always comes back in one way or another.. I suspect a problem with the governor.. Could there be another problem?
I also have another problem with the tranny that really doesn't bother me too much but I'm sure that something isn't right.. The transmission locks up normally but sometimes, when I accelerate (with less than 30% throttle), the car vibrates a lot (sometimes for a few seconds) when the converter is unlocking..
Any input on those problems is appreciated!
Last edited by GrandSportC3; 06-14-2007 at 01:33 PM.
06-14-2007, 01:39 PM
#2
Race Director
I had some shifting problems and it was a bad TV cable plus debris in the valve body. Have you tried to readjust the TV cable? I dropped the pan to have a look for metal in case the trans was bad when I had problems. There wasn't any problems that I could see so I installed a shift kit. I found debris in the valve body. After cleaning it and putting the new cable on, mine has been OK. Maybe Pete K will chime in with his experience.
06-14-2007, 01:51 PM
#3
Team Owner
Thread Starter
I had some shifting problems and it was a bad TV cable plus debris in the valve body. Have you tried to readjust the TV cable? I dropped the pan to have a look for metal in case the trans was bad when I had problems. There wasn't any problems that I could see so I installed a shift kit. I found debris in the valve body. After cleaning it and putting the new cable on, mine has been OK. Maybe Pete K will chime in with his experience.
06-14-2007, 01:56 PM
#4
Race Director
With the cable problem on mine, it would move it's adjustment. It was worn out. When I tried to readjust it I found that it would not adjust properly and I asked Pete K to be sure it was worn out.
Good idea with the pan. The debris I found in the valve body was hard clear plastic looking, almost like popcorn husks.
Good idea with the pan. The debris I found in the valve body was hard clear plastic looking, almost like popcorn husks.
06-14-2007, 02:15 PM
#5
Team Owner
Thread Starter
With the cable problem on mine, it would move it's adjustment. It was worn out. When I tried to readjust it I found that it would not adjust properly and I asked Pete K to be sure it was worn out.
Good idea with the pan. The debris I found in the valve body was hard clear plastic looking, almost like popcorn husks.
Good idea with the pan. The debris I found in the valve body was hard clear plastic looking, almost like popcorn husks.
so I really don't know what to expect...
06-14-2007, 02:51 PM
#6
Race Director
I hope mine had the filter changed but who knows! Have you taken one down before? On mine I had to becareful of letting the weight of the pan rest on one or two bolts, thus bending the pan. I checked the pan for level when I had it off. I put a drain plug kit in it. There is a notch in the gasket for the tiny hole in the passenger side of the trans, servo vent I think this is. Pete K always says to be very careful not to plug it. I rocked the pan to slosh more fluid out of it and did not end up spilling any. I have made a pretty big mess before. 
There was only a small amount of silver sediment on the magnet in mine and adhered to the bottem of the pan. It needed to be scrubbed off. If you let the valve body down, it's pretty heavy!
There was only a small amount of silver sediment on the magnet in mine and adhered to the bottem of the pan. It needed to be scrubbed off. If you let the valve body down, it's pretty heavy!
06-14-2007, 02:55 PM
#7
Team Owner
Thread Starter
I hope mine had the filter changed but who knows! Have you taken one down before? On mine I had to becareful of letting the weight of the pan rest on one or two bolts, thus bending the pan. I checked the pan for level when I had it off. I put a drain plug kit in it. There is a notch in the gasket for the tiny hole in the passenger side of the trans, servo vent I think this is. Pete K always says to be very careful not to plug it. I rocked the pan to slosh more fluid out of it and did not end up spilling any. I have made a pretty big mess before.
There was only a small amount of silver sediment on the magnet in mine and adhered to the bottem of the pan. It needed to be scrubbed off. If you let the valve body down, it's pretty heavy!
There was only a small amount of silver sediment on the magnet in mine and adhered to the bottem of the pan. It needed to be scrubbed off. If you let the valve body down, it's pretty heavy!
I'm not planning on dropping the valve body down.. Only if I have to.. I might pull out the governer and look at it also.. Where does the governor sit on a 700R4? On the 200R4, it was in the back of the tranny, near where the speedo cable mounted..
06-14-2007, 03:21 PM
#8
Race Director
If I remember right it is on the drivers side toward the back. If I don't remember right, you can't miss it. It is a large round cover that is about as big around as a beer can. It is pressed in so may take some prying to remove.
06-14-2007, 03:35 PM
#9
Team Owner
Thread Starter
Thanks! Sounds like the same location as the 200R4...
06-14-2007, 04:15 PM
#10
The governor cover is on the drivers side, rear of the trans case. No need to drop the pan. It is likely sticking intermittently.
If you prefer, you can simply pop the cover and install a new gm governor in there. They are approx $50. Buy a new o-ring for the governor cap at the same time. I have the part number somewhere, if you need it. If rebuilding or swapping the governor does not fix it, you may have a plugged governor screen. It is accessable by dropping the valve body.
If you prefer, you can simply pop the cover and install a new gm governor in there. They are approx $50. Buy a new o-ring for the governor cap at the same time. I have the part number somewhere, if you need it. If rebuilding or swapping the governor does not fix it, you may have a plugged governor screen. It is accessable by dropping the valve body.
06-14-2007, 05:34 PM
#11
Instructor
Try changeing fuild and filter first-- its not that costly and may fix the problem. On my 88 the first time I changed the fuild and filter the filter fell out as I was dropping the pan. I was amazed that I wasnt having more trouble, but it was just street miles and no raceing.
Good Luck
Good Luck
06-14-2007, 08:50 PM
#12
Team Owner
Thread Starter
The governor cover is on the drivers side, rear of the trans case. No need to drop the pan. It is likely sticking intermittently.
If you prefer, you can simply pop the cover and install a new gm governor in there. They are approx $50. Buy a new o-ring for the governor cap at the same time. I have the part number somewhere, if you need it. If rebuilding or swapping the governor does not fix it, you may have a plugged governor screen. It is accessable by dropping the valve body.
If you prefer, you can simply pop the cover and install a new gm governor in there. They are approx $50. Buy a new o-ring for the governor cap at the same time. I have the part number somewhere, if you need it. If rebuilding or swapping the governor does not fix it, you may have a plugged governor screen. It is accessable by dropping the valve body.
06-14-2007, 08:51 PM
#13
Team Owner
Thread Starter
Try changeing fuild and filter first-- its not that costly and may fix the problem. On my 88 the first time I changed the fuild and filter the filter fell out as I was dropping the pan. I was amazed that I wasnt having more trouble, but it was just street miles and no raceing.
Good Luck
Good Luck
I'm actually racing the car a lot.. I only have the car since about 1.5 months and already raced 5 bracket races with it... (20 passes total)
Ran a 14.22 @96 mph in 93 degrees with a DA above 3500.. Not bad for a stock C4. It even has the original paper air filter
I bet that I'll hit 13.80's in winter or even better.
Last edited by GrandSportC3; 06-14-2007 at 08:53 PM.
06-15-2007, 05:59 AM
#14
Race Director
I've been through this twice, Olivier...with me it seems to have been the TV Cable...mine would not shift at part throttle until over 5000 rpm...the last time it happened was against you at BMP....it "fixed" itself on the way home..it "unfixed" itself the next week at Orlando...
I seem to have corrected it by adjusting the TV Cable to the stock setting amd draining the fluid, refilling and putting in a new filter....I raced it last weekend at OSW and it shifted fine...
The TV Cable attaches to the throttle valve so a goofed up TV Cable can impair your shift points...as you press on the gas pedal the cable moves the throttle valve against a spring...this raises the fluid pressure through a hole to a level that lets the tranny shift...if that valve is not moving correctly, either due to a bad cable setting or a tiny piece of debris, it will take until high rpm to build enough fluid pressure for the tranny to shift....
I believe this is what was happening to mine...good luck with yours...
I seem to have corrected it by adjusting the TV Cable to the stock setting amd draining the fluid, refilling and putting in a new filter....I raced it last weekend at OSW and it shifted fine...
The TV Cable attaches to the throttle valve so a goofed up TV Cable can impair your shift points...as you press on the gas pedal the cable moves the throttle valve against a spring...this raises the fluid pressure through a hole to a level that lets the tranny shift...if that valve is not moving correctly, either due to a bad cable setting or a tiny piece of debris, it will take until high rpm to build enough fluid pressure for the tranny to shift....
I believe this is what was happening to mine...good luck with yours...
06-15-2007, 08:03 AM
#15
Team Owner
Thread Starter
I've been through this twice, Olivier...with me it seems to have been the TV Cable...mine would not shift at part throttle until over 5000 rpm...the last time it happened was against you at BMP....it "fixed" itself on the way home..it "unfixed" itself the next week at Orlando...
I seem to have corrected it by adjusting the TV Cable to the stock setting amd draining the fluid, refilling and putting in a new filter....I raced it last weekend at OSW and it shifted fine...
The TV Cable attaches to the throttle valve so a goofed up TV Cable can impair your shift points...as you press on the gas pedal the cable moves the throttle valve against a spring...this raises the fluid pressure through a hole to a level that lets the tranny shift...if that valve is not moving correctly, either due to a bad cable setting or a tiny piece of debris, it will take until high rpm to build enough fluid pressure for the tranny to shift....
I believe this is what was happening to mine...good luck with yours...
I seem to have corrected it by adjusting the TV Cable to the stock setting amd draining the fluid, refilling and putting in a new filter....I raced it last weekend at OSW and it shifted fine...
The TV Cable attaches to the throttle valve so a goofed up TV Cable can impair your shift points...as you press on the gas pedal the cable moves the throttle valve against a spring...this raises the fluid pressure through a hole to a level that lets the tranny shift...if that valve is not moving correctly, either due to a bad cable setting or a tiny piece of debris, it will take until high rpm to build enough fluid pressure for the tranny to shift....
I believe this is what was happening to mine...good luck with yours...
I hope to get to it this weekend..How do I determine factory setting on the TV cable??
06-15-2007, 09:19 AM
#16
Race Director
Adjust the cable? Press in the D shape butten on the cable, it's up by the TB. Then slide the pintle toward the back of the car. After that just mash the gas pedal. You can rotate the throttle at the TB to, my new cable is pretty tight and can take a lot of force to adjust there so I use the gas pedal.
06-15-2007, 01:25 PM
#17
Race Director
Adjust the cable? Press in the D shape butten on the cable, it's up by the TB. Then slide the pintle toward the back of the car. After that just mash the gas pedal. You can rotate the throttle at the TB to, my new cable is pretty tight and can take a lot of force to adjust there so I use the gas pedal.
LT-1's are different...I could never find directions for the LT-1, only for the l98 motor...I got a guy at the drag strip to help me out and I am still hoping we did it right...lol...I am going to make a separate post on this issue so keep an eye on that for your answer, Olivier...
06-15-2007, 01:34 PM
#18
Race Director
Ahh good catch, I didn't note the LT1. Here is a huge thread about the LT1 cable.
http://forums.corvetteforum.com/show...t=lt1+tv+cable
http://forums.corvetteforum.com/show...t=lt1+tv+cable
06-15-2007, 03:16 PM
#20
Instructor
I'll definetely change the fluid..
I'm actually racing the car a lot.. I only have the car since about 1.5 months and already raced 5 bracket races with it... (20 passes total)
Ran a 14.22 @96 mph in 93 degrees with a DA above 3500.. Not bad for a stock C4. It even has the original paper air filter
I bet that I'll hit 13.80's in winter or even better.
I'm actually racing the car a lot.. I only have the car since about 1.5 months and already raced 5 bracket races with it... (20 passes total)
Ran a 14.22 @96 mph in 93 degrees with a DA above 3500.. Not bad for a stock C4. It even has the original paper air filter
I bet that I'll hit 13.80's in winter or even better.
Good Luck