A few random mishaps that I have no idea about...

[87TTypeKid]

Ok, I will start with the simple one.

1) In the morning (on very cold days), the first time the car actually moves forward it hesitates a little bit, almost in the manner that it might if the rear brakes were hanging up a bit, or the diff was being moody. But its only that one time in the morning, then it will never do it again for the rest of the day....odd. Ideas?

2) Although this used to be related to only one specific spot on the highway (odd), its happened randomly at a few other places. My guess is its related to the rate at which I'm decelerating and the angle of the road. Cruising at about 75 mph on the highway, when I let off the gas at this one particular area, the transmission decides that it goes into a phase where it doesn't like to kick down anymore when you give the car some throttle. It will stay in overdrive for a really long time, and it takes quite a bit of gas to get it to kick down into 3rd. Eventually when it does, the shift is rather violent sounding (moreso than the others that I'm used to with the shift kit), and it usually clears itself up after one or two of them. You can even kick the gas in spurts and it just feels like you are doing it in a manual trans. car. Ideas? The trans did this a lot after it was rebuilt about a year and a few months ago and has been behaving ever since. My guess is that something internally gets stuck and will eventually free itself. Since I dont know transmissions very well aside from the basics, any input would help. Thanks all.


Oh, and one last thing- Cruising speed on the highways makes me pull about 10 in/Hg of vacuum. Is this in the normal range? I remember it being lower...14-16...seems like its pushing a bit harder to keep the car moving...could this be my shot suspension up front putting the wheels at an angle that creates a lot of resistance?

 

[XLR8]

#2 sounds like the converter not unlocking. You may need a new TCC solenoid. When cruising at a steady speed, see if tapping the brakes raises your RPM 200 or so - if not your torque conerter is not unlocking.

 

[Project TNX]

Does it ever stall, because I had your number 1 problem but it would occasionaly stall and it was the TCC Solenoid.

 

[turbobuickman]

I can see the TCC being at fault for #1 and #2. Do the test suggested by xlr8. BTW you need to be going over 45 mph or whatever speed your chip locks the TCC for the test to work.

 

[Lee_Burough]

Torque Converter Lock-up from VortexBuicks.com

Torque Converter Lock Up



In normal operation, the torque converter is locked up when the tan/black wire from the solenoid is grounded by the ecm. By inserting a switch between Terminal F of the ALDL connector and ground, one can manually lock up the torque converter by flipping the switch and completing the circuit to ground. Chip makers can program their chips to allow the ecm to lock the converter under w.o.t. conditions at a user selected miles per hour. For street cars, I prefer to do it manually in order to prolong the converter life. If it locks at full throttle every time, the clutches will wear more quickly and there is really no need to do so unless one is racing and striving for every tenth.

If the converter refuses to lock up under normal operation, or when forced by a manual switch, one has to determine if the problem is in the circuitry, or in the solenoid, itself.

The circuitry, as shown below, is simple and one should verify it's operation first. Power is taken from the ECM/SOL fuse. After verifying it is good, one should go straight to the switch mounted on the brake pedal lever. If the switch is properly adjusted, there should be 12 volts in the purple wire coming from the switch when the key is ON. In order for the this to happen, the switch has to be adjusted so that the button on it is fully depressed when the brake pedal is not being depressed. Sometimes the pedal will begin to be positioned a bit lower than normal and the button on the switch will not be depressed enough to complete the circuit through the switch that originates at the fuse. Sometimes one can lift up on the pedal slightly and complete the circuit so that the purple wire shows 12 volts. In this case, the tcc switch must be pressed a couple of more clicks thru its mounting bracket. If the pedal cannot be lifted, then the switch should be pressed down a couple of clicks to see if this completes the circuit. I have found that the contacts inside the switch can be burnt, but, the switch may be opened, the contacts filed clean, and the switch will work when reassembled and reinstalled.

When voltage is verified at the purple wire and the torque converter does not work, one needs to confirm continuity in the tan/black wire. As seen below, one should see continuity between A7 on the ecm and the other end under the car in the plug that goes onto the tranny connector. I often short cut the process and see if I have continuity between Terminal F on the ALDL and the plug under the car. This does not confirm the connection all the way to the ecm, however.

If one finds continuity in the tan/black wire, then the tcc solenoid in the tranny has probably died. Many have become toast after this number of years.

Look here for the write up and a flow chart from the shop manual. There are several transmission related links at gnttype.org, and Here too.

 

[87TTypeKid]

It wouldnt surprise me if the solenoid is on its way out. Any ideas about why it seemed related to one certain set of conditions (that one location and speed on the road)...it habitually happens ONLY at that spot, minus a time here and there...and I commute every day in this car, so I notice it a lot.

Also, um, any ideas why my 2-3 shift is hesitant as hell when the car is at sub-zero temperatures like its been outside in my area (Jersey) lately? The 2-3 is always a bit picky and rarely happens as hard as it should, and the delay between the two gears when it first rolls in the morning sometimes gets as bad as half a second- equivalent to a slow shift in a manual, to make an analogy as to how the car moves and feels during the shift.

Now, I am assuming the 200r4 and the 700r4 are relatively similar, so is there a cable that controls shift pressure? If so and its out of whack, would this cause the 2-3 shift to be a little weak? I hope the trans isnt on its way out..just had the damn thing rebuilt..it isnt doing what my old Camaro's trans was doing before it bit the dust, so I'm not too worried. Once the trans is warm, 2-3 isnt too bad...it has its days.

I really appreciate the input- I'm learning every day. Thanks