TC or tune
#1
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TC or tune
Coulld this be a torque converter or tune? My wifes C5 H/C A4 with 3200 stall is giving me a couple of problems that I cant seem to tune out
1. In 4th gear, when the TC locks up, it feels like it is constantly engaging and disengaging causing a "skip" feeling. I can shift back to 3rd, ands it is smooth as slilk so its not a skip. I can move the lock up around and it moves to the spot I set it.
2. After installing a set of heads, I was tweaking the tune and it mysteriously has lost all of it's low end punch. When I go WOT from a dead stop, it bogs really bad. I have tried several different timing settings but it still seems to bog just like the stall is not working.
Any thoughts?
1. In 4th gear, when the TC locks up, it feels like it is constantly engaging and disengaging causing a "skip" feeling. I can shift back to 3rd, ands it is smooth as slilk so its not a skip. I can move the lock up around and it moves to the spot I set it.
2. After installing a set of heads, I was tweaking the tune and it mysteriously has lost all of it's low end punch. When I go WOT from a dead stop, it bogs really bad. I have tried several different timing settings but it still seems to bog just like the stall is not working.
Any thoughts?
#2
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As for #1 it may be the PWM, if you have not already, you may want to set that table to 100 all the time? Its probably better for your converter too. I had a similar problem to #2 with my camaro, and it was ASR (traction control) related. You may want to try pulling the fuse on the traction control and see if that has anything to do with it. My car picked up 57 MPH in the 1/4 after pulling the fuse. From bog to blowing the tires off.
#3
Sometimes is just better to start over with a stock tune. Don't know why, but the tune file somehow gets corrupted and doesn't work as expected.
A fresh tune file fixes many issues.
A fresh tune file fixes many issues.
#4
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Sounds like the TC is locking/unlocking... You may need to adjust the light throttle lockup to avoid having the converter lock when engine RPMs are lower than drivetrain revolutions at that speed.
See http://forum.efilive.com/showthread....4-shift-points
See http://forum.efilive.com/showthread....4-shift-points
#5
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Thanks guys
I have set the PWM table to 100%, and it didn't seem to help (thought it would)
It actaully acts a lot like the traction control, since that would pull timing to reduce power and tire spin
I have palyed with the part throttle lock up, and where ever I put it, it moves the problem there. I set it to 60mph, to see if it would move it, and since my wife drives faster than that, it is still giving her problems. She says it is "skipping". I say both problems are driving me nuts
I have set the PWM table to 100%, and it didn't seem to help (thought it would)
It actaully acts a lot like the traction control, since that would pull timing to reduce power and tire spin
I have palyed with the part throttle lock up, and where ever I put it, it moves the problem there. I set it to 60mph, to see if it would move it, and since my wife drives faster than that, it is still giving her problems. She says it is "skipping". I say both problems are driving me nuts
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Thanks guys
I have set the PWM table to 100%, and it didn't seem to help (thought it would)
It actaully acts a lot like the traction control, since that would pull timing to reduce power and tire spin
I have palyed with the part throttle lock up, and where ever I put it, it moves the problem there. I set it to 60mph, to see if it would move it, and since my wife drives faster than that, it is still giving her problems. She says it is "skipping". I say both problems are driving me nuts
I have set the PWM table to 100%, and it didn't seem to help (thought it would)
It actaully acts a lot like the traction control, since that would pull timing to reduce power and tire spin
I have palyed with the part throttle lock up, and where ever I put it, it moves the problem there. I set it to 60mph, to see if it would move it, and since my wife drives faster than that, it is still giving her problems. She says it is "skipping". I say both problems are driving me nuts
And about the bogging, when you go WOT from a dead stop, does it bog for a few seconds and then somehow find its rythm and take off? If so, check the upper MAP regions of the VE table in the Lower RPM columns, they may need to be adjusted after the head install. I had the exact same symptom I described, and that's what fixed it.
#7
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Well:in regards to the bucking, Ive checked the fluid level, have the TCC duty cycle at 100% raised the lock up to 62mph, and that's when it starts , so it must be the convertor locking and unlocking
What am I missing??
What am I missing??
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#10
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This is the last one I have
I moved the part throttle lock ups lower, but it still does it at any speed AFTER lock up
If I shift to 3rd, where I have no lock up until a high speed, it never does it
I moved the part throttle lock ups lower, but it still does it at any speed AFTER lock up
If I shift to 3rd, where I have no lock up until a high speed, it never does it
#15
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since TCC apply pressure is regulated from line pressure, you should physically check that your line pressure is not falling down.
#16
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How do I read the pressure? Are you saying I have to install a mecanical guage somehow, or is there somthing in HPTuner that will read it?
#17
There is no pressure sensor to log transmission pressure.
You need to hook a mechanical pressure gauge, it is 1/8 NPT, use this chart to command the Motor current and see if the gauge matches
Start with the highest mA value of the table and go down. Less mA gives more PSI
You need to hook a mechanical pressure gauge, it is 1/8 NPT, use this chart to command the Motor current and see if the gauge matches
Start with the highest mA value of the table and go down. Less mA gives more PSI
#19
Yes, that's right
Get a long flex tubing and hook the gauge in front of you and drive the car
I tape it to the windshield so I can watch it the moment the problem happens
Get a long flex tubing and hook the gauge in front of you and drive the car
I tape it to the windshield so I can watch it the moment the problem happens