Mechanics

MY TRANSMISSION IS MAKING NOISE AND NOT SHIFTING INTO OVERDRIVE

1997 Oldsmobile Delta 88

1997 delta 88, transmission is not shifting to the overdrive gears Originally, my transmission was making a noise like a low flying helicopter. Took down the pan and found not only normal shavings but pea size bits of metals. So change out transmission and while taking it out of car, went ahead and changed out all the gaskets on the engine.
Car was running and shifting fine for the first 300 miles, then I had to go on a job about 100 miles from home, I noticed that the car was overheating and when I opened the hood and felt the top hose it collasped. So I bought a new hose and radiator fluid, but as I took off the hose, no fluid was coming out-so I opened the radiator to find it empty.
I changed out the hose and added fluid, but the radiator would not fill and the oil level was rising, the engine did a hydro-lock. Called a wrecker truck to haul the car in.

I removed the plenum, hand turned the crank after removing the spark plugs to get water out of cylinder, took the oil pan down and completely drained the engine of oil and cleaned oil pan. Did a fresh oil change, changed out spark plugs, replaced the plenum with new, installed new pvc. Started the car on the first try, test drove it down my drive way but did not take on road because it was late at night and would do in the morning.

Next morning, took the car on the road but no more than 500' feet noticed that the car did not do the normal shifting. Usually, the car will shift, go maybe to 2500 rpm and shift to the next gear-but it would not shift until maybe 4000 rpm-turned around and brought back into my shop.

I was looking at the vacuum modular to make sure vacuum hoses were secure and for leaks, the car started fine again, so again I went for a test drive, but again it would not shift in the proper pattern. Since I was on the road, I went to pay a bill about 2 miles down the road. The car would shift into the gears but not the normal overdrive with lower rpms


Usually at 70 mph, my car is about 2100rpm but it was over 3000rpm. I made my payment and as I was leaving the window the car stopped. It did thankfully start back up again but was running very rough, I inched home and as I turned down my driveway, no foot on accelerator the rpms was rising to about 2500 rpm, car running rough and black smoke coming from exhaust-pulled back into shop, turned car off and was not able to restart

I changed out all the vacuum lines except the one in the back that services the accesories.
The engine is running sweet, went back on the road to test it and it is still not shifting properly.

Before the original hydrolock problem the car was shifting fine, so now I am stuck and am not sure what to look for anymore to solve this shifting problem. In essence, I am not shifting into my overdrive gears

Oh yea, I did change the throttle body sensor when I changed out the plenum, the radiator fluid is fine and so is the oil.

Help! I need my car so I can go to work and I need it to run correctly as I am a contract Network engineer and when I get calls the clients networks are down and need to be brought back up ASAP and it does not look good when my vehicle goes down.

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Pursur
October 10, 2011.




The throttle cable or tv cable that goes on the throttle body adjusts throttle pressure which assists in shifting. Did you change the adjustment>

Roy

ASEMaster6371
Oct 10, 2011.
I was reading about that but the book states that on 92 and later models the 4T60-E and 4T65-E electonic controlled transmission is not equipped with the TV cable assembly- I have a 97 so I dismissed that possible resolution, maybe I should readdress and confirm.
But I can say that I did not change any of the accelerator cables.
I found my computer code reader and read the code, it was PO122-so now I do know without doubt that it is with the throttle and I did change out the Throttle Position Sensor and must admit that I was not aware that it had to be adjusted, but as all of this was going on the wire connection going to the breather broke right next to the connector, so close that a pair of wire strippers were too big and could not strip the wire, so I cut the connection, stripped and soldered extra wire into the line so that it would not be so tight-it worked fine-but by the time I finished that it was 11: 15pm, I needed to walk away for a while so I hung it up for the night and plan to work on it this afternoon.
I did find how to adjust the TPS and plan to try that later this afternoon,
boy when it rains it pours, because when this is finished I have to work on my gravely 30hp lawnmower, the PTO clutch shaft bent-I am ready to get a 24pk and I don't drink.
Code P0122-adjust TPS, in your professional opinion, am I correct?
Thank you

Tiny
Pursur
Oct 10, 2011.
You are on the right track. Try disconnecting the battery and hooking it up again for the tps. The computer needs to be turned stupid, as I call it, so it can see the true voltage.

Roy

ASEMaster6371
Oct 10, 2011.
I pulled the throttle body and set the TPS, I also noticed that one of the pins in the connector was pushed down, so I corrected it and disconnected the battery to make the computer stupid. I then went for a test drive but it is was still not shifting properly. It does shift just not those higher gears that drops the rpm. Dropit back into the shop and read the computer again, still pulled the P0122, nor once but twice, one in freeze frame the other not.
I changed out the shifter because I guess it is a vacuum bleeder was broken, reinstalled the original that was on the transmission I had pulled out.
The shifting was a little better but still not right. What is and where is the pedal sensor?

Tiny
Pursur
Oct 11, 2011.
I guess that was a kind of dumb question, as I have continued to read and find nothing on the pedal sensor so if it safe to assume it seems to me that the TPS and pedal sensor is the same.

I am still pulling P0122 error, twice once in the freeze frame and the other not in a freeze frame. Is it possible that because not adjusting the TPS the first time that it shorted. I do understand the theory of electricity but am intimidated when reading devices.
Not sure how to proceed.
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Tiny
Pursur
Oct 12, 2011.
Your car is too old for a pedal sensor. You have a tps on the throttle body but that is it.

Roy

ASEMaster6371
Oct 12, 2011.
Okay, so since I am still pulling a P0122 code it is possible that it is shorted?
I am not pulling any transmission code errors but I was reading about the TCC, is it safe to assume that since I am not pulling any P0700 codes that there is nothing wrong with this sensor?

At this point I am planning to buy another new TPS for at this point it seems like my only option and it would not be the first time that I bought a brand new part that was defective coming straight out the box.

Tiny
Pursur
Oct 12, 2011.
Yes, no trans codes, you are good, but it does not say anything about the internal hydraulics. It could still be an issue.

One more thing I thought about is the governor. There is a gear under it that is plastic and tends to dish in the center which means it does not turn as fast as it should and could contribute to your issue.

Roy

ASEMaster6371
Oct 12, 2011.
Whoa, now you have stumped me! I have worked on manual transmissions but never the internals of automatic, when those go bad buy a rebuilt one and replace is how that is usually handled.
As far as hydraulics, I only know how to work on tractor and jack hydralic, so not to sure about "internal hydraulics" of an automatic transmission.
I do know that the newly installed transmission was working fine before the overheating of the engine, that the oil looks fine, the right color, the level is correct and no burnt smells and no noises coming from it.
The only experience with governors is to know that some commerical fleets put them on carbureted trucks to control the speed of the units to prevent overspeeding and to save on fleet fuel expenses but I was unaware that governors were put on fuel injected vehicles

I have not read anything about a governor on the car, just where would that be located? I only have a Haynes book and do know how to research on the internet, but do not access to a real SHOP manual. Do you sale real Shop manuals?

I am not able to work on the car at normal working hours this week because whoopie, I have been choosen for jury duty, so even accessing parts this week is a little complicated.
Thanks

Tiny
Pursur
Oct 12, 2011.

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