Help...I was told this is a PCM/Tuning problem.
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Joined: Dec 2001
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From: Ft. Lauderdale, FL, USA
Help...I was told this is a PCM/Tuning problem. While cruising normally at say 65 mph, and I gently apply more pedal just to gradually speed up a little bit, nothing happens and it just revs right to my redline if I let it. The car doesn't move at all. But before I applied the extra pedal it was cruising perfectly at the proper rpm for that speed. I have to either hit the brake and let it slow down a little OR manually downshift to "3", then back to "D" for it to hook back up.
When I let it hook back up it will stay hooked up as fast as I want to go, it only does this weird un-hooking thing after I'm cruising steady for a little while.
Other than this, the tranny/converter seems to work perfectly during all other types and speeds of driving.
One more thing I notice in every gear: If I mash the gas all the way to the floor, it will over-rev for a second at the top of each gear before it shifts.
Thanks.
When I let it hook back up it will stay hooked up as fast as I want to go, it only does this weird un-hooking thing after I'm cruising steady for a little while.
Other than this, the tranny/converter seems to work perfectly during all other types and speeds of driving.
One more thing I notice in every gear: If I mash the gas all the way to the floor, it will over-rev for a second at the top of each gear before it shifts.
Thanks.
TECH Senior Member
Joined: Nov 2001
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From: Lake Zurich, IL
Sounds like it's time for a trans rebuild... Check the fluid to see if it's burnt...
When my 2nd trans went, if I mashed the gas it'd rev up like it was in neutral (from a stop or roll) but if I eased into it, it'd be ok most of the time... generally i'd have to feather the gas to get it to shift gears...
Did this start happening immediately after you got a new tune? If not, then it's definetly not the tune and most likely the transmission
I don't know transmissions well enough to know exactly what's going on though... so not sure what actual parts may be busted if it is the trans...
When my 2nd trans went, if I mashed the gas it'd rev up like it was in neutral (from a stop or roll) but if I eased into it, it'd be ok most of the time... generally i'd have to feather the gas to get it to shift gears...
Did this start happening immediately after you got a new tune? If not, then it's definetly not the tune and most likely the transmission
I don't know transmissions well enough to know exactly what's going on though... so not sure what actual parts may be busted if it is the trans...
Thread Starter
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Joined: Dec 2001
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From: Ft. Lauderdale, FL, USA
Originally Posted by horist
Sounds like it's time for a trans rebuild... Check the fluid to see if it's burnt...
When my 2nd trans went, if I mashed the gas it'd rev up like it was in neutral (from a stop or roll) but if I eased into it, it'd be ok most of the time... generally i'd have to feather the gas to get it to shift gears...
Did this start happening immediately after you got a new tune? If not, then it's definetly not the tune and most likely the transmission
I don't know transmissions well enough to know exactly what's going on though... so not sure what actual parts may be busted if it is the trans...
When my 2nd trans went, if I mashed the gas it'd rev up like it was in neutral (from a stop or roll) but if I eased into it, it'd be ok most of the time... generally i'd have to feather the gas to get it to shift gears...
Did this start happening immediately after you got a new tune? If not, then it's definetly not the tune and most likely the transmission
I don't know transmissions well enough to know exactly what's going on though... so not sure what actual parts may be busted if it is the trans...
Fluid is full and very clean. No burnt smell at all.
I guess its the tune than.
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Joined: Nov 2001
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From: Lake Zurich, IL
so, if you're cruising at 65, and increase the throttle... does it downshift then bang the limiter? or does it feel like it's going into neutral? (65mph in w/locked converter is prolly 2400 RPM or so?) so it goes from 2400 up to red line and still in OD?
Thread Starter
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From: Ft. Lauderdale, FL, USA
Originally Posted by horist
so, if you're cruising at 65, and increase the throttle... does it downshift then bang the limiter? or does it feel like it's going into neutral? (65mph in w/locked converter is prolly 2400 RPM or so?) so it goes from 2400 up to red line and still in OD?
I can also take my foot off-and-on the gas and nothing happens, its just like it popped into nuetral. I have to manually shift it to "3" to make it hook up again.
TECH Senior Member
Joined: Nov 2001
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From: Lake Zurich, IL
hmmm... there's nothing in tuning that I can think of that can cause that to happen... when you get it on it, the PCM can command the torque converter to lock or unlock and can command the car to change gears... Line pressure is controlled via the vacuum line (Vacuum modulated) ...
sounds like under high torque either the converter is slipping like crazy or the transmission isn't able to hold the gear
sounds like under high torque either the converter is slipping like crazy or the transmission isn't able to hold the gear
Thread Starter
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From: Ft. Lauderdale, FL, USA
Damn man, I just can't get a break. I almost want to buy a new tranny and a new PCM and a new converter to just start over. This is the 3rd NEW tranny I've had and the third NEW converter, and the 3rd NEW tune, this just sucks.
Maybe I'll get lucky and Futral can figure out whats wrong when he does all my engine upgrades and gives it yet another new tune.
Thanks anyway for the help.
Maybe I'll get lucky and Futral can figure out whats wrong when he does all my engine upgrades and gives it yet another new tune.
Thanks anyway for the help.
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You should use a scanning software and log what is happening when this occurs. Get speed, gear commanded, TCC commanded, TPS, load, line pressure, and anything else available that is trans related from your software.
You always post about racing from a roll, 50 - 150 mph. Maybe its time for a M6 swap and sintered iron clutch.
You always post about racing from a roll, 50 - 150 mph. Maybe its time for a M6 swap and sintered iron clutch.
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Thread Starter
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Joined: Dec 2001
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From: Ft. Lauderdale, FL, USA
Originally Posted by Orange Crush 408
Either go with a built 6 speed and or do an a3, those 4l60e's are junk.
Teching In
Joined: Sep 2003
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the 80's wont fit in the tunnel they are massive and you would have to end up beating or cutting the floor, i would either got with a 350 or 400 set up. i have a built tranny that sitting the back of the shop snice i dediced to swap out the trannys. theres maybe 100 miles on the damn thing im jus tgoin with more power with the new set up.
Thread Starter
TECH Veteran
Joined: Dec 2001
Posts: 4,117
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From: Ft. Lauderdale, FL, USA
Originally Posted by smokn346
the 80's wont fit in the tunnel they are massive and you would have to end up beating or cutting the floor, i would either got with a 350 or 400 set up. i have a built tranny that sitting the back of the shop snice i dediced to swap out the trannys. theres maybe 100 miles on the damn thing im jus tgoin with more power with the new set up.
