Trans guys help me out.
TECH Resident
Joined: May 2006
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First lets try something simple, disconnect the vacuum line going to the vacuum modulator, and see if this solves the problem, let me know asap, if not, you should put a pressure gauge on this and lets see what the pressures are at the different throttle openings, otherwise this is guess work. Once you know the pressures, then if you need to make any changes you will know what to do from the start. If the vacuum modulator needs to be adjusted (to lower line pressure), you will need to shorten the length of the pin. Pressure at WOT should be no less than 210lbs., and not more than 235lbs.
I just pulled the modulator out and it does not have a screw in center of the mod where the hose goes. They is no way that I see to adjust it. It does have a dent it the side of it. I think it happened when it was shipped.
Last edited by Kiss_My_99SS; Jun 13, 2007 at 07:30 PM.
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
I have not yet witnessed a unit have WOT 1-2 shift issues related to a 46-Mod installation and we have several out there hitting hard as I type this. That being said, you mentioned that the problem happens at WOT and is only related to the 1-2 shift.
As you stated it is commanding the shift and regarless of table settings it does not shift at WOT. "The shift rpm is 6000 the rev is set to 6600. On the scan you can see when it comands it to shift and as soon as it comands it just to the rev limiter." What happens immediately after this... do you release the throttle and it shifts? Or you stay in the throttle and it eventually shifts? Based on that comment alone, it sounds to me that the band is not being applied. Check the servo seals, the 1-2 accumulator and the 1-2 shift valve also check the solenoid 0-ring. Those are not likely causes as it has a part throttle shift, but I have seen stranger things.
Where are the part throttle and WOT shift tables set at? Feel free to p.m. me those files and I'll carry them next door to Xtreme Horsepower and we'll take a look at them for you, we might see something you don't, you never know. '98 and '99 models can be very, very difficult to tune the shift points. However... we do not have much trouble with the 1-2 shift, usually it is the 2-3 shift.
Other than the modulator, what hydraulic modifications were made at the time of the rebuild?
Hang in there... you'll learn allot going through this process and be better off for it in the long run!
p.s. ... the adjustment screw is behind the epoxy at the back of the housing there, but don't fool with that. Adjust pressure by changing the length of the pin. I would suggest that if the 2/3 shift is good then the pin length is good. But you do need to measure the line pressure if you think it is incorrect. Establish a baseline just as Dana said. The dent is perfectly normal, looks correct and just fine. Pull a vaccum on it while you have it out and see if it holds... if so it should be fine.
g
edited to read 2/3 shift not 3/4 shift in both places
As you stated it is commanding the shift and regarless of table settings it does not shift at WOT. "The shift rpm is 6000 the rev is set to 6600. On the scan you can see when it comands it to shift and as soon as it comands it just to the rev limiter." What happens immediately after this... do you release the throttle and it shifts? Or you stay in the throttle and it eventually shifts? Based on that comment alone, it sounds to me that the band is not being applied. Check the servo seals, the 1-2 accumulator and the 1-2 shift valve also check the solenoid 0-ring. Those are not likely causes as it has a part throttle shift, but I have seen stranger things.
Where are the part throttle and WOT shift tables set at? Feel free to p.m. me those files and I'll carry them next door to Xtreme Horsepower and we'll take a look at them for you, we might see something you don't, you never know. '98 and '99 models can be very, very difficult to tune the shift points. However... we do not have much trouble with the 1-2 shift, usually it is the 2-3 shift.
Other than the modulator, what hydraulic modifications were made at the time of the rebuild?
Hang in there... you'll learn allot going through this process and be better off for it in the long run!
p.s. ... the adjustment screw is behind the epoxy at the back of the housing there, but don't fool with that. Adjust pressure by changing the length of the pin. I would suggest that if the 2/3 shift is good then the pin length is good. But you do need to measure the line pressure if you think it is incorrect. Establish a baseline just as Dana said. The dent is perfectly normal, looks correct and just fine. Pull a vaccum on it while you have it out and see if it holds... if so it should be fine.
g
edited to read 2/3 shift not 3/4 shift in both places
Last edited by Gilbert@Ace Racing; Jun 13, 2007 at 08:05 PM.
.................. .............
I let out of it and then it will shift. I can run it up to 4000 RPM PT and it will shift......
My bin file and log file can be found here.
http://www.hptuners.com/forum/showth...0921#post90921
Originally Posted by Ratchthed
I have not yet witnessed a unit have WOT 1-2 shift issues related to a 46-Mod installation and we have several out there hitting hard as I type this. That being said, you mentioned that the problem happens at WOT and is only related to the 1-2 shift.
As you stated it is commanding the shift and regarless of table settings it does not shift at WOT. "The shift rpm is 6000 the rev is set to 6600. On the scan you can see when it comands it to shift and as soon as it comands it just to the rev limiter." Or you stay in the throttle and it eventually shifts?
I let out of it and then it will shift. I can run it up to 4000 RPM PT and it will shift......
My bin file and log file can be found here. http://www.hptuners.com/forum/showth...0921#post90921
Based on that comment alone, it sounds to me that the band is not being applied. Check the servo seals, the 1-2 accumulator and the 1-2 shift valve also check the solenoid 0-ring. Those are not likely causes as it has a part throttle shift, but I have seen stranger things.
Where are the part throttle and WOT shift tables set at? Feel free to p.m. me those files and I'll carry them next door to Xtreme Horsepower and we'll take a look at them for you, we might see something you don't, you never know. '98 and '99 models can be very, very difficult to tune the shift points. However... we do not have much trouble with the 1-2 shift, usually it is the 3-4 shift.
Other than the modulator, what hydraulic modifications were made at the time of the rebuild?
Hang in there... you'll learn allot going through this process and be better off for it in the long run!
p.s. ... the adjustment screw is behind the epoxy at the back of the housing there, but don't fool with that. Adjust pressure by changing the length of the pin. I would suggest that if the 3/4 shift is good then the pin length is good. But you do need to measure the line pressure if you think it is incorrect. Establish a baseline just as Dana said. The dent is perfectly normal, looks correct and just fine. Pull a vaccum on it while you have it out and see if it holds... if so it should be fine.
g
As you stated it is commanding the shift and regarless of table settings it does not shift at WOT. "The shift rpm is 6000 the rev is set to 6600. On the scan you can see when it comands it to shift and as soon as it comands it just to the rev limiter." Or you stay in the throttle and it eventually shifts?
I let out of it and then it will shift. I can run it up to 4000 RPM PT and it will shift......
My bin file and log file can be found here. http://www.hptuners.com/forum/showth...0921#post90921
Based on that comment alone, it sounds to me that the band is not being applied. Check the servo seals, the 1-2 accumulator and the 1-2 shift valve also check the solenoid 0-ring. Those are not likely causes as it has a part throttle shift, but I have seen stranger things.
Where are the part throttle and WOT shift tables set at? Feel free to p.m. me those files and I'll carry them next door to Xtreme Horsepower and we'll take a look at them for you, we might see something you don't, you never know. '98 and '99 models can be very, very difficult to tune the shift points. However... we do not have much trouble with the 1-2 shift, usually it is the 3-4 shift.
Other than the modulator, what hydraulic modifications were made at the time of the rebuild?
Hang in there... you'll learn allot going through this process and be better off for it in the long run!
p.s. ... the adjustment screw is behind the epoxy at the back of the housing there, but don't fool with that. Adjust pressure by changing the length of the pin. I would suggest that if the 3/4 shift is good then the pin length is good. But you do need to measure the line pressure if you think it is incorrect. Establish a baseline just as Dana said. The dent is perfectly normal, looks correct and just fine. Pull a vaccum on it while you have it out and see if it holds... if so it should be fine.
g
I let out of it and then it will shift. I can run it up to 4000 RPM PT and it will shift......
My bin file and log file can be found here.
http://www.hptuners.com/forum/showth...0921#post90921
Yes the scew is under that glue or epoxy , You can use it to make small changes in line presure, Larger changes require changing the pin as noted. The dent does concern me. What im talking about is just one of several possibilites , as I told you the hole feeding the solenoids could be to large but I do know the line being way to high for a combination of reasons can cause solenoid flooding basically you cant shift because the solenoids cant vent fluid fast enough and since this happens on both 1-2 and the 2-3 shift its as likley a possibility as any , You said the unit is new and that its shifts good in all but WOT? another possibility is this, is there any fluid in the hose near the engine? If so the modulator may have failed.
Originally Posted by Kiss_My_99SS
I just pulled the modulator out and it does not have a screw in center of the mod where the hose goes. They is no way that I see to adjust it. It does have a dent it the side of it. I think it happened when it was shipped.
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FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
It will be tomorrow but I'll see what I can find out for ya! I am not registered at HP Tuners but I am sure the guys next door can handle it. We'll see.
Be sure to remove the 1-2 solenoid and inspect the valve very closely. It is very easy to remove the 1-2 accumulator housing with the pan off... just do not lose the one check ball... mark it's location if you are not familiar. Now's the time to take a long hard look around while the pan is off!
g
Be sure to remove the 1-2 solenoid and inspect the valve very closely. It is very easy to remove the 1-2 accumulator housing with the pan off... just do not lose the one check ball... mark it's location if you are not familiar. Now's the time to take a long hard look around while the pan is off!
g
FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Well as it turns out I was heading out and they were next door. I brought up your car and the HPTuners .bin file... They told me they do not use HPTuners. EFI LiVe, Diablosport and others but they do not support that software.
Sooo. That didn't work out.... but we did discuss your issues and one comment Arvil had was to verify that your downshift mph is lower than your upshift mph. Depending on the gear ratio you will want to see a seperation of about 5-10 mph. Downshift tables are set lower than upshift by at least 5 mph.
How'd the hydraulics look?
g
Sooo. That didn't work out.... but we did discuss your issues and one comment Arvil had was to verify that your downshift mph is lower than your upshift mph. Depending on the gear ratio you will want to see a seperation of about 5-10 mph. Downshift tables are set lower than upshift by at least 5 mph.
How'd the hydraulics look?
g
I think I will put the force motor back in it and see what it does. What sould i check while I have the pan off?
The way I set my car to shift is I 0 out the MPH table at WOT so that it shifts by the RPM that I set.
The way I set my car to shift is I 0 out the MPH table at WOT so that it shifts by the RPM that I set.
Last edited by Kiss_My_99SS; Jun 13, 2007 at 10:36 PM.
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Originally Posted by performabuilt
Yes the scew is under that glue or epoxy , You can use it to make small changes in line presure, Larger changes require changing the pin as noted. The dent does concern me. What im talking about is just one of several possibilites , as I told you the hole feeding the solenoids could be to large but I do know the line being way to high for a combination of reasons can cause solenoid flooding basically you cant shift because the solenoids cant vent fluid fast enough and since this happens on both 1-2 and the 2-3 shift its as likley a possibility as any , You said the unit is new and that its shifts good in all but WOT? another possibility is this, is there any fluid in the hose near the engine? If so the modulator may have failed.
I would try what I suggested and clean the stuff off the screw and turn it 1 turn counter clockwise , I really think solenoid flooding may be your issue , Either that or change it back over to PCS . I know some will disagree but I just dont care for the modulator set up , May be why we do not offer it .
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I dont think it could cause the issues your having but still a good time to fix it. But make sure its not actually from the overflow above it which could be a sign that the trans is actually slipping and generating heat
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TECH Resident
Joined: May 2006
Posts: 969
Likes: 119
Did you disconnect the vacuum hose going to the vacuum modulator yet to see if it made a change? If this fixes it then I will tell you what is causing this, if not put a pressure gauge on it, and get some readings on this!!! Once you do this you will be able (most likely) to solve this. I use the vacuum modulator on many setups and it has proven to be quite trouble free. Dana
Originally Posted by PBA
Did you disconnect the vacuum hose going to the vacuum modulator yet to see if it made a change? If this fixes it then I will tell you what is causing this, if not put a pressure gauge on it, and get some readings on this!!! Once you do this you will be able (most likely) to solve this. I use the vacuum modulator on many setups and it has proven to be quite trouble free. Dana
I had allready removed the vacuum modulator before you posted.
I put the PCS back on. I checked the tune everything looked right there. OD and D slip when you put it in gear move the shifter to 2 or 1 nice and firm. This is when you are taking off. The car will roll without touching the gas when you let off the brake. Give it a little gas and it will slip for a second then put fine.It still will not shift at WOT.
Did the car act like this before you put the PCS back in? As far as slipping ?
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You may have reassembled the valve wrong.
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FormerVendor
Joined: Oct 2006
Posts: 3,123
Likes: 3
From: D-F/W
Sorry for not being on the phone with you long... had a customer come in. I hope Johns' advice was useful He is a great guy and we are glad to have him.
Good luck, let us know how it works out for you!
g
Good luck, let us know how it works out for you!
g
Originally Posted by Ratchthed
Sorry for not being on the phone with you long... had a customer come in. I hope Johns' advice was useful He is a great guy and we are glad to have him.
Good luck, let us know how it works out for you!
g
Good luck, let us know how it works out for you!
g
John was very helpful. I was able to find the part I need and will try to fix it later today when I get off work. I will post the results later.
Thanks again for your help.