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ok, so I am having a new issue and hopefully its something easy. The car has started to shift wierd. For one, it seems to not want to lock up the TC firmly or at all sometimes, i'll go into overdrive, and i'll watch the tach with hardly any load it was lock up slowly not quickly as it did. Then it would lock on 3rd gear which it will slowly but the slightest load will cause it to disengauge. It never used to do this. I replaced all the shift solenoids last year and its been fine since. Could it be a repeat performance in the making?

I know I have been messing around with all the wiring for my PC1122 codes which has slowed down since cleaning connectors. Maybe I have disturbed something else?

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Any codes? You might be paying too much attention to it, drive it for a while and see what happens. The next time you are on a highway, do more than 41 mph, at that point the TC should engage, keep steady pressure on the gas pedal with your right foot, watch the TACH, and lightly press the brake, you should see the RPMs rise. Try that test. Its possible that your TPS causing this also, try disconnecting the battery so that the system goes through a relearn.

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Sounds to me just like Scotty said.

I had that problem with mine a while ago,but it didn't want to get fixed until I did the Idle Learn Procedure.

(You have to through each gear and stay in each like 20 seconds or something).

I don't know how to do it on a '96,but that's how you do it on a '95.

I'm not sure if It's in the"How to" section,or maybe you have a manual.

Florin

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Sounds to me just like Scotty said.

I had that problem with mine a while ago,but it didn't want to get fixed until I did the Idle Learn Procedure.

(You have to through each gear and stay in each like 20 seconds or something).

I don't know how to do it on a '96,but that's how you do it on a '95.

I'm not sure if It's in the"How to" section,or maybe you have a manual.

Florin

Ok, it locks at 40 just fine, it tries to lock at 30MPH if I stay on a constant speed... Then in i give it slight gas it unlocks but at 40 it stays constant no issues.. I may be looking to into it... I will do a disconnect of the battery and let it completely drain out then I will let it relearn... Now you say each gear does that mean manual shift or just drive normal?

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Florin, are you referring to a transmission shift adapt reset? Mike

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

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Ok, So i disconnected the battery for 1 hour, I found the idle re-learn procedure and completed that fine... Drovethe car around lightly ( no WOT ) ran good... Now at 41 MPH it goes to OD just fine and locks up nice, I can steadly increase the gas and the tranny stays locked well even at 1/4 throttle down from wherever I am driving.. The funny thing is, at about 33 MPH it locks up slightly with rpms not rising, then at about 37MPH it unlocks again on a straight road with no increased gas applied or removed. As soon as you give it a slight hair line gas increase it unlocks and stays unlocked till OD is on at 41+MPH.. That is wierd.. As long as its not a issue showing itself I could car less. By the way, No codes from anything after this latest reset. I gave the car half throttle turning cause someone was flying up behind me, and I broke free the tires and did a nice little burnout.. wasnt expecting that at all.

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Mine has done this at times and it seems odd, it seems to have stopped doing it. It will lock up the TC in 3rd, normally under certain conditions, if you are driving her easy, its possible she is locking up.. in 3rd and popping right out at any sign of the engine laboring at all.

Note this however, I have been driving mine like an old man, very easy, because I have a bad front engine mount and as a result of the gas prices, its possible that, the prior shift adapts, where I was beating her, are not compatible with my recent driving habit changes causing the oddness in the shifting. That is why I suggested a re-learn.

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Mine has done this at times and it seems odd, it seems to have stopped doing it. It will lock up the TC in 3rd, normally under certain conditions, if you are driving her easy, its possible she is locking up.. in 3rd and popping right out at any sign of the engine laboring at all.

Note this however, I have been driving mine like an old man, very easy, because I have a bad front engine mount and as a result of the gas prices, its possible that, the prior shift adapts, where I was beating her, are not compatible with my recent driving habit changes causing the oddness in the shifting. That is why I suggested a re-learn.

Interesting... Other than that all is well.. I do feel better that yours is/was doing the same thing... Next question for giggles... Where is the VSS located on this car 96 seville 4.6L, inside trans or outside? I did get a VSS code last year and all the MPH gauge went nuts, did it once and that was it.

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Its a piece of cake to change, it's on the TOP of the passenger side output shaft housing, I recently posted a photo of its location try searching VSS, vehicle speed sensor, Mike

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Here is the thread I was talking about, I put a photo in it showing the location of the VSS, Mike

http://caddyinfo.ipbhost.com/index.php?sho...le+Speed+Sensor

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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With all of the corrosion you have found, I would try cleaning the connector/plug first, Mike

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Mine has done this at times and it seems odd, it seems to have stopped doing it. It will lock up the TC in 3rd, normally under certain conditions, if you are driving her easy, its possible she is locking up.. in 3rd and popping right out at any sign of the engine laboring at all.

Note this however, I have been driving mine like an old man, very easy, because I have a bad front engine mount and as a result of the gas prices, its possible that, the prior shift adapts, where I was beating her, are not compatible with my recent driving habit changes causing the oddness in the shifting. That is why I suggested a re-learn.

Interesting... Other than that all is well.. I do feel better that yours is/was doing the same thing... Next question for giggles... Where is the VSS located on this car 96 seville 4.6L, inside trans or outside? I did get a VSS code last year and all the MPH gauge went nuts, did it once and that was it.

By the way, I also feel better that you have a similar 'problem' occuring. I was going to start a thread inquiring whether there were any initial symptoms when the shift solenoids began to go bad, I was thinking that my shift solenoids might be on the blink, but since you said you changed YOURS last year and you appear to be having the same 'lock up' problems, I am having, I was able to eliminate my shift solenoids as a cause..

My tranny appears to be shifting better over the last week, but I have been driving it harder also

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Hey mike, when your shift solenoids go bad you will know they went... You will never shift gears or loose some of them. definetly not that... I was doing some reasearch this evening and found out that the TCC gets its readings to lock up from the VSS and a monetary loss of the speed sensor signal would cause the TCC to unlock.. A long trip as I just made on my car may have caused some sludge or particles to find there way to the VSS... So I will clean my old one first if not its what 30 bucks, just replace it.. I will do it tommarow so I will keep you posted! Thanks for all the help thus far mike!

Oh also 1 other question, when turning off traction control the car skips 1st gear all together and starts in 2nd.. I never heard of such a thing and the car actually looses alot of power shutting that off, which i would figures should be opposite with it off... IDK wierd..

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Yes, that happens to protect the transaxle and axles so that they are not damaged with unfettered spinning because the traction control is off. If you started in first without the traction control, you would spin uncontrollably and put the drive train components at risk, so they start you in second gear.

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Ok so I took the VSS out and it shows 1.5K or 1500 Ohms... Does anyone know the specs on this part? It's 13 dollars locally so I am putting a new one in regardless but I would love to know if this one is going or out of spec...

In the Transmission section of the manual, page 7A-8, in the 96 manual there is a chart called Component Resistances:

The VSS should be 1260 to 1540 ohms at 20 degrees C (68 degrees F), resistance to ground should be LESS THAN 10M OHM (JimD what does 10M ohm mean?)

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Ok so I took the VSS out and it shows 1.5K or 1500 Ohms... Does anyone know the specs on this part? It's 13 dollars locally so I am putting a new one in regardless but I would love to know if this one is going or out of spec...

In the Transmission section of the manual, page 7A-8, in the 96 manual there is a chart called Component Resistances:

The VSS should be 1260 to 1540 ohms at 20 degrees C (68 degrees F), resistance to ground should be LESS THAN 10M OHM (JimD what does 10M ohm mean?)

Mike, 10M = 10 milli ohms. I tested the resistance to the new one, it was .5 Less than my old one.. I installed it and ran the car, It does lock at about 35MPH and hold nicely better than before... Locks up right at 41MPH firm.. So as far as I am concerned $12 dollars did the trick for now... I would replace it, if you have time... took me 10 minutes to get it out and install the new one. I am happy with the results!

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Ok so I took the VSS out and it shows 1.5K or 1500 Ohms... Does anyone know the specs on this part? It's 13 dollars locally so I am putting a new one in regardless but I would love to know if this one is going or out of spec...

In the Transmission section of the manual, page 7A-8, in the 96 manual there is a chart called Component Resistances:

The VSS should be 1260 to 1540 ohms at 20 degrees C (68 degrees F), resistance to ground should be LESS THAN 10M OHM (JimD what does 10M ohm mean?)

Mike, 10M = 10 milli ohms. I tested the resistance to the new one, it was .5 Less than my old one.. I installed it and ran the car, It does lock at about 35MPH and hold nicely better than before... Locks up right at 41MPH firm.. So as far as I am concerned $12 dollars did the trick for now... I would replace it, if you have time... took me 10 minutes to get it out and install the new one. I am happy with the results!

Hey thanks for the feedback, that is good to know. I may change mine. Drive it for awhile and let us know what you think.

I knew the M meant million, what I didn't know was why such a high resistance. Does this mean that there is VERY LITTLE resistance/connection to ground, and if there IS resistance it means that the COIL inside is shorting out? I hope that makes sense.

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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....The VSS should be 1260 to 1540 ohms at 20 degrees C (68 degrees F), resistance to ground should be LESS THAN 10M OHM (JimD what does 10M ohm mean?)

If I could retrain the GM specification department and the tech writers, they would learn to talk about that VSS resistance reading in terms like "....should be 1,400 Ohms plus or minus 140 Ohms (10%)". But alas....

Mike- 10M Ohm is 10 MegOhms and Mega is 10 to the 6th power. Or 10,000,000 Ohms.

Milli is 10 to the minus 3 power and is not used in measuring resistance; resistance values than than 1,000 ohms are always expressed as the value expected even when that value is less than 1 Ohm. Examples like this: 890 Ohms or 75 Ohms or 6 Ohms or finally as 0.5 Ohms.

I'm handicapped trying to explain the abbreviation relationships without the ability to use scientific notation.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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Thanks Jim, can you help me understand the mathematical concept behind it, let me explain.

At 10,000,000 ohms does this mean that there is a GOOD STRONG connection or does this mean that there is virtually NO connection to ground.

If you look at my post above it states LESS than 10M ohms. Would 20M ohms be LESS, than 10M ohms? I am trying to understand the concept.

Can you explain that to me, is this a very strong or very very weak connection to ground? My gut tells me this is a relatively weak connection to ground and anything greater than 10M ohms implies that the internal coil is shorted. Am I making sense? I am trying to understand the concept.

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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....At 10,000,000 ohms does this mean that there is a GOOD STRONG connection or does this mean that there is virtually NO connection to ground.

In an automotive sensor or control circuit, 10M Ohms is a very high value; can be considered to be an "open" circuit. Your SM gives a value like this as a test to be sure the sensor is not referenced to chassis ground and a resistance reading of 10M Ohms or greater would indicate the sensor signal is in fact not referenced to ground.

If you look at my post above it states LESS than 10M ohms. Would 20M ohms be LESS, than 10M ohms? I am trying to understand the concept.

Disregard the multiplier ( the "M" part) and just compare the numbers; 20 would be more than 10. Likewise 20M Ohm would be more than 10M Ohm.

....My gut tells me this is a relatively weak connection to ground and anything greater than 10M ohms implies that the internal coil is shorted.

You are going to have to learn a new language when dealing with electrical values, Mike. Terms like weak and strong are not precise enough to determine if a component can be expected to perform as intended. That is why the troubleshooting charts provide resistance values where appropriate.

Neither my '98 or '04 manuals provide a continuity check to ground for the VSS. GM maybe felt is was a misleading value?

We sure have wandered off the shifting and lockup!! I'm happy to steer you through the fuzzy parts of this Mike, but it sure would go faster in a classroom.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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....At 10,000,000 ohms does this mean that there is a GOOD STRONG connection or does this mean that there is virtually NO connection to ground.

In an automotive sensor or control circuit, 10M Ohms is a very high value; can be considered to be an "open" circuit. Your SM gives a value like this as a test to be sure the sensor is not referenced to chassis ground and a resistance reading of 10M Ohms or greater would indicate the sensor signal is in fact not referenced to ground.

If you look at my post above it states LESS than 10M ohms. Would 20M ohms be LESS, than 10M ohms? I am trying to understand the concept.

Disregard the multiplier ( the "M" part) and just compare the numbers; 20 would be more than 10. Likewise 20M Ohm would be more than 10M Ohm.

....My gut tells me this is a relatively weak connection to ground and anything greater than 10M ohms implies that the internal coil is shorted.

You are going to have to learn a new language when dealing with electrical values, Mike. Terms like weak and strong are not precise enough to determine if a component can be expected to perform as intended. That is why the troubleshooting charts provide resistance values where appropriate.

Neither my '98 or '04 manuals provide a continuity check to ground for the VSS. GM maybe felt is was a misleading value?

We sure have wandered off the shifting and lockup!! I'm happy to steer you through the fuzzy parts of this Mike, but it sure would go faster in a classroom.

Thanks for your patience Jim,

Yes we did, get off topic, but I think this kind of discussion can be instructional to us all here. I may sound dense, but I am just trying to get the concept down, I think I am there. First I need to substitute OPEN AND CLOSED circuit for WEAK and STRONG.

That said, can you answer yes or no to this question?

Your statement:

Disregard the multiplier ( the "M" part) and just compare the numbers; 20 would be more than 10. Likewise 20M Ohm would be more than 10M Ohm

My conclusion, from this is. A 20M ohm circuit is MORE OPEN than a 10M ohm circuit, is that correct?

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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Thanks for your patience Jim,

Yes we did, get off topic, but I think this kind of discussion can be instructional to us all here. I may sound dense, but I am just trying to get the concept down, I think I am there. First I need to substitute OPEN AND CLOSED circuit for WEAK and STRONG.

That said, can you answer yes or no to this question?

Your statement:

Disregard the multiplier ( the "M" part) and just compare the numbers; 20 would be more than 10. Likewise 20M Ohm would be more than 10M Ohm

My conclusion, from this is. A 20M ohm circuit is MORE OPEN than a 10M ohm circuit, is that correct?

YES, that is one way to express the concept.

Not to nitpick the terminology, but there are applications where 10M Ohms would be the expected value and the true measure of an open circuit condition would be infinite resistance which some models of (LCD display) Ohmeters display as "OL".

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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I love the lesson we have got into! At my express version, my old unit at 1.53Ohms ran worse than a new one at 1.49Ohms, hardly any difference in ohm's but who knows at working capacity what was going on.. Just drove the car around.. All is fine and strong... So Far... Thanks Guys!

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Thanks Jim

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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