Transmission and Engine Woes on my '91 98 RegElite
91olds98
05-27-2005, 11:38 PM
Four things: Engine Shudder, Transmission OD lock, Horn, and Cruise Control.
First, my 1991 Olds 98 Regency Elite has some wierd thing with the engine. When going up a slight hill at about 50mph the engine will pulse at low rpms when in overdrive. If you shift out of OD then the shudder goes away. I was reading a prev. forum where someone had the same problem, but never posted a solution. Anyone have any ideas?
Second, my transmission is acting up. I believe that there is a device that, when the trans is not under heavy load (ie cruising speed) it locks the torque converter to the engine output shaft to keep the engine and the trans moving at the same speed (or something to that effect). However, mine does not always lock and becomes unlocked VERY easily (about 5% throttle). Also, if I pass someone, and the trans drops down a gear, the locker will not engage once I reach cruising speed again. To fix this solution I will probably design an over-riding circuit, but to know the cause of the problem would probably be a much better idea. Any help on the issue would be great. Thanks
Also, my horn doesn't work - checked the fuses, all are ok. Checked the horns, both still work if I run a jumper wire. Probably switch on steering wheel? Anyone else had similar problems?
Lastly, my cruse control is acting up. It works most of the time, but after driving for about 45min the cruise will not register the vehicle speed. It still stays on; the pedal is partially depressed and the light on the dash stays lit, but the Accel switch won't work, and the whole car slowy decreases speed. I have to turn the cruise off and then on again in order to get it to reset. Some time ago, we had the same problem, and then put a new battery in and this seemed to clear up the problem for a while. I was thinking that the problem is a faulty voltage regulator in the computer somewhere, but don't really know. Possibly a sensor somewhere? Anyone got a clue?
Thanks in advance everyone.
First, my 1991 Olds 98 Regency Elite has some wierd thing with the engine. When going up a slight hill at about 50mph the engine will pulse at low rpms when in overdrive. If you shift out of OD then the shudder goes away. I was reading a prev. forum where someone had the same problem, but never posted a solution. Anyone have any ideas?
Second, my transmission is acting up. I believe that there is a device that, when the trans is not under heavy load (ie cruising speed) it locks the torque converter to the engine output shaft to keep the engine and the trans moving at the same speed (or something to that effect). However, mine does not always lock and becomes unlocked VERY easily (about 5% throttle). Also, if I pass someone, and the trans drops down a gear, the locker will not engage once I reach cruising speed again. To fix this solution I will probably design an over-riding circuit, but to know the cause of the problem would probably be a much better idea. Any help on the issue would be great. Thanks
Also, my horn doesn't work - checked the fuses, all are ok. Checked the horns, both still work if I run a jumper wire. Probably switch on steering wheel? Anyone else had similar problems?
Lastly, my cruse control is acting up. It works most of the time, but after driving for about 45min the cruise will not register the vehicle speed. It still stays on; the pedal is partially depressed and the light on the dash stays lit, but the Accel switch won't work, and the whole car slowy decreases speed. I have to turn the cruise off and then on again in order to get it to reset. Some time ago, we had the same problem, and then put a new battery in and this seemed to clear up the problem for a while. I was thinking that the problem is a faulty voltage regulator in the computer somewhere, but don't really know. Possibly a sensor somewhere? Anyone got a clue?
Thanks in advance everyone.
MagicRat
05-28-2005, 12:05 AM
Some easy solutions:
1. You are lugging the engine. There is nothing wrong with your car.
All these V6 and THM 440 trans combinations will rev down to 1300 - 1400 rpm in overdrive. However, when you give the engine a bit of gas to get over a hill, you are lugging the engine and placing it under unneccesary stress.
Shift out of OD under these circumstances. Let the engine rev a bit more to cope with the load. This is a common practise and is why all overdrive transmissions have an OD lock out button or shifter. At lower highway speeds in hilly terrain, leaving the trans in D and NOT OD is the correct operating procedure.
2. Adjust the transmission's throttle position cable.
The cable is likely a bit tight, that is it thinks the throttle is opening up further than it actually is.
This cable is attached to the throttle valve on the intake manifold and goes to the trans. When you step on the gas pedal, it pulls on the cable. There is a simple adjustable bracket on the manifold, usually tools are not required. Just adjust it a very small amount and see if you notice a difference.
As for the lock up not locking up....there is an electric lock up solinoid inside the transmission itself which controls the converter. This solinoid is behind the side cover on the drivers side of the trans and is a bit tricky to change. These THM 440 trans are notorious for developing sticky solinoids when they get old.
3. This car has a horn relay....somewhere. If you push on the horn button and you do not hear a faint 'click' from under the dash, the horn relay is not working. Either it has no power (my first guess is the button's electrical contacts in the steering wheel are dirty/rusty) or the relay is bad.
4. I have no suggestion right now for the cruise.
1. You are lugging the engine. There is nothing wrong with your car.
All these V6 and THM 440 trans combinations will rev down to 1300 - 1400 rpm in overdrive. However, when you give the engine a bit of gas to get over a hill, you are lugging the engine and placing it under unneccesary stress.
Shift out of OD under these circumstances. Let the engine rev a bit more to cope with the load. This is a common practise and is why all overdrive transmissions have an OD lock out button or shifter. At lower highway speeds in hilly terrain, leaving the trans in D and NOT OD is the correct operating procedure.
2. Adjust the transmission's throttle position cable.
The cable is likely a bit tight, that is it thinks the throttle is opening up further than it actually is.
This cable is attached to the throttle valve on the intake manifold and goes to the trans. When you step on the gas pedal, it pulls on the cable. There is a simple adjustable bracket on the manifold, usually tools are not required. Just adjust it a very small amount and see if you notice a difference.
As for the lock up not locking up....there is an electric lock up solinoid inside the transmission itself which controls the converter. This solinoid is behind the side cover on the drivers side of the trans and is a bit tricky to change. These THM 440 trans are notorious for developing sticky solinoids when they get old.
3. This car has a horn relay....somewhere. If you push on the horn button and you do not hear a faint 'click' from under the dash, the horn relay is not working. Either it has no power (my first guess is the button's electrical contacts in the steering wheel are dirty/rusty) or the relay is bad.
4. I have no suggestion right now for the cruise.
91olds98
05-29-2005, 11:20 AM
Ok - Thanks for the advice on the first few issues (namely 1, and 3) But I looked at the throttle cable and see nothing going to the transmission. There is a secondary cable going to the cruise control vaccum module which is mounted on top of the transmission, but there is no throttle cable going to the trans itself. The only cable attatched to the trans is the shifter cable. Any thoughts?
Alright - scratch that first comment. I went back and looked, and apparently this was a late 1991 model year because this one has the 4T60-E transmission, not the standard 4T60 that was used in the early part of 1991 that used the throttle vavle cable. I looked it up in the Haynes manual and apparently this model trans is controlled electronically.
Also, I was talking to somone else who had heard that the cruise control problem could have been caused by a faulty wire that was shorting out or something. If this is the case in my situation, where would I look for such a problem, and could this also cause the transmission torque converter lock-up solenoid issue?
Ok. Im back (again). Here's a thought. What if the tps sensor was faulty. Could this be the cause of the cruise control issue (the cruise computer thinking the throttle is open more than it actually is) and the trans torque conv lock issue (ecm thinking that the throttle is open too far)?
Alright - scratch that first comment. I went back and looked, and apparently this was a late 1991 model year because this one has the 4T60-E transmission, not the standard 4T60 that was used in the early part of 1991 that used the throttle vavle cable. I looked it up in the Haynes manual and apparently this model trans is controlled electronically.
Also, I was talking to somone else who had heard that the cruise control problem could have been caused by a faulty wire that was shorting out or something. If this is the case in my situation, where would I look for such a problem, and could this also cause the transmission torque converter lock-up solenoid issue?
Ok. Im back (again). Here's a thought. What if the tps sensor was faulty. Could this be the cause of the cruise control issue (the cruise computer thinking the throttle is open more than it actually is) and the trans torque conv lock issue (ecm thinking that the throttle is open too far)?
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