2-3 shift is going bad
#1
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2-3 shift is going bad
As i'm accelerating, right before it shifts from 2nd to 3rd....the car jumps up in revs. Literally right before it shifts. And depending on how much throttle I use the amount of rpms that it jumps, changes. For example, when i'm just cruising along it jumps up 1000rpm suddenly, right before it shifts. If i'm using more throttle it'll jump up 1500-2000 rpm.
Any ideas?
Any ideas?
#3
I'm afraid your 3/4 clutches are failing. Check the flui condition, is it full. Does i have a burnt pungeant odor?
I saw that this is a relatively new unit in your previous post. You might want to speak to the folks that built it and see what they have to say.
g
I saw that this is a relatively new unit in your previous post. You might want to speak to the folks that built it and see what they have to say.
g
#4
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this is the old unit, which is stock, just a shift kit...just curious as to what it might be that failed in my old one before a new one goes in.
fluid is clean, not full all the way but in between the hash marks
trans has 55k and has been sprayed on a good amount
fluid is clean, not full all the way but in between the hash marks
trans has 55k and has been sprayed on a good amount
#5
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Just curious did you have a previos post after a cam PO101 ? This is a MAF code and could be the source of your present failure, And improperly calibrated MAF can affect trans line presure and result in a failure. I also noticed this occured after you did some engine mods
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Just curious did you have a previos post after a cam PO101 ? This is a MAF code and could be the source of your present failure, And improperly calibrated MAF can affect trans line presure and result in a failure. I also noticed this occured after you did some engine mods
In my case it didn't. However after another tune w/no TQ management it gradually started to slip and then I put TQ management back in and now it still slips.
I think the trans started to hurt itself from no tq management and the power I was putting down.
I did notice this morning that when the car is still warming up and I drive it slow, the 2-3 shift is fine, but as soon as the temps get up and I get moving for a minute or so, it starts to happen.
#7
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Actually no the damage can take a while. Improper line control depending on how bad it is can kill the trans quickly or over a period of time, There is actually a GM TSB about the MAF and how it can damage the trans when out or calibration. The TSB has to do with contaminated MAFfrom over oiling filter. However engine mods not properly calibrated for can cause similar issues. The PO101 is likley what killed your trans you have now and could conceivably damage the new one if not addressed. I would get that corrected.
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Actually no the damage can take a while. Improper line control depending on how bad it is can kill the trans quickly or over a period of time, There is actually a GM TSB about the MAF and how it can damage the trans when out or calibration. The TSB has to do with contaminated MAFfrom over oiling filter. However engine mods not properly calibrated for can cause similar issues. The PO101 is likley what killed your trans you have now and could conceivably damage the new one if not addressed. I would get that corrected.
#10
Just as an FYI for anyone who followed this thread and is interested to know the outcome.
The OP borught us the car, we removed and dissasembled the unit. What we found was the 3/4 clutches burnt, with more than a 1/4" of clearance in the stack when we got to it.
The accumulator pistons were plastic, one of them had broken. Basically the center of it, that rides on the pin, had been broken out and several small pieces of it were found throughout the tranmsission. Including one piece that was found in the 3rd gear feed hole of the valve body plate. In addition the accumulator spring was broken into pieces.
This unit had a shift kit installed previously, it is an example of why shift kits should be installed by professionals who understand what they are looking at. Not just professionals mind you... but pros who understand these units.
g
I will save these parts for getting pics up soon... I'm in computer hell right now or I'd do it tonight.
The OP borught us the car, we removed and dissasembled the unit. What we found was the 3/4 clutches burnt, with more than a 1/4" of clearance in the stack when we got to it.
The accumulator pistons were plastic, one of them had broken. Basically the center of it, that rides on the pin, had been broken out and several small pieces of it were found throughout the tranmsission. Including one piece that was found in the 3rd gear feed hole of the valve body plate. In addition the accumulator spring was broken into pieces.
This unit had a shift kit installed previously, it is an example of why shift kits should be installed by professionals who understand what they are looking at. Not just professionals mind you... but pros who understand these units.
g
I will save these parts for getting pics up soon... I'm in computer hell right now or I'd do it tonight.
Last edited by Gilbert@Ace Racing; 02-16-2008 at 08:53 PM.