Tuning or Stall issue?
Thread Starter
Racer
Joined: Oct 2001
Posts: 255
Likes: 0
From: Helena, AL
Tuning or Stall issue?
Last week my car was dyno tuned and I added 3.42's and a Yank 3000 rpm stall. The car runs like a raped ape but I have noticed something odd. When I am in traffic and easy on the gas, the 2-3 shift feels like it shifts up to 3rd then quickly back to 2nd and then 3rd. Kind of a jerky hesitation. I think it is around 2200-2300 when the shift occurs. If I am really light on the gas it doesn't happen and if I am on it hard it doesn't happen. I have been told that when you are getting used to driving a car with a higher stall converter there are some quirks to get used to when you are in traffic. I was wondering if this is one of them or if it might be a glitch in the tuning.
Safety Car
Joined: Aug 2000
Posts: 4,154
Likes: 1
From: Murphy TX
Cruise-In II Veteran
I'd want to verify fluid level first, then tuning. If the upshift and downshift curves are very close together you can see this sort of thing. Another longshot possibility would be that you're feeling the converter lock and unlock in 3rd (3-lock-release-lock rather than 2-3-2-3). Check the same things in that case.
Le Mans Master
Joined: Sep 2003
Posts: 6,386
Likes: 0
From: Just a little outside San Antonio, Texas
I agree with ToplessTexan.
I did this same mod on my 2004 A4 coupe before trading for my Vert so I have some personal experience on this subject.
The A4 tranny is very sensitive to its fluid level being even a little low so make sure the garage test drives it a time or two and checks the fluid level after each test drive.
Secondly, the new gears means that you'll need to have the shift points readjusted (yes, a PCM tune) because you're hitting the rmp shift point earlier because of the lower gear ratios.
I did this same mod on my 2004 A4 coupe before trading for my Vert so I have some personal experience on this subject.
The A4 tranny is very sensitive to its fluid level being even a little low so make sure the garage test drives it a time or two and checks the fluid level after each test drive.
Secondly, the new gears means that you'll need to have the shift points readjusted (yes, a PCM tune) because you're hitting the rmp shift point earlier because of the lower gear ratios.
Race Director
Joined: Aug 1999
Posts: 15,466
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From: GARDENA Ca, State Of Konfusion
St. Jude Donor '05
Originally Posted by JBH
I have been told that when you are getting used to driving a car with a higher stall converter there are some quirks to get used to when you are in traffic. I was wondering if this is one of them or if it might be a glitch in the tuning.
Thread Starter
Racer
Joined: Oct 2001
Posts: 255
Likes: 0
From: Helena, AL
Originally Posted by wallstAL
I have no quirks or issues with the high stall, I think you have tuning issues.
Pro
Joined: Apr 2002
Posts: 658
Likes: 4
From: North York Ontario
Originally Posted by ToplessTexan
I'd want to verify fluid level first, then tuning. If the upshift and downshift curves are very close together you can see this sort of thing. Another longshot possibility would be that you're feeling the converter lock and unlock in 3rd (3-lock-release-lock rather than 2-3-2-3). Check the same things in that case.
If yes then make sure that your tuner has knowledge of this condition before you go, otherwise you may not get results.
I feel that there is a point were the completed 2-3 upshift loads to the point of unlocking the converter and then locking as the load is released at the end of the shift. (Exactly as you describe). I have not seen any consequences from this.
If you get the condition solved it would be nice to know how.
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Burning Brakes
Joined: Apr 2003
Posts: 908
Likes: 4
From: TROY MI
Originally Posted by JBH
Last week my car was dyno tuned and I added 3.42's and a Yank 3000 rpm stall. The car runs like a raped ape but I have noticed something odd. When I am in traffic and easy on the gas, the 2-3 shift feels like it shifts up to 3rd then quickly back to 2nd and then 3rd. Kind of a jerky hesitation. I think it is around 2200-2300 when the shift occurs. If I am really light on the gas it doesn't happen and if I am on it hard it doesn't happen. I have been told that when you are getting used to driving a car with a higher stall converter there are some quirks to get used to when you are in traffic. I was wondering if this is one of them or if it might be a glitch in the tuning.
Thread Starter
Racer
Joined: Oct 2001
Posts: 255
Likes: 0
From: Helena, AL
Originally Posted by JTE
I had a similar problem with my Yank 3000. It was tuning related and fixed by my current tuner. My previous tuner had a lot to learn. 
I took it for a spin last night and I think it is actually locking and unlocking instead of a 2-3-2-3 shift.
I am going to check the fluid this weekend when I get back in town.
It was the converter locking and unlocking. Dan at FLP corrected it for me. I don't know the specifics. 
Burning Brakes
Joined: Apr 2003
Posts: 908
Likes: 4
From: TROY MI
Originally Posted by JBH
Do you know what they changed in the tune to correct the problem?
I took it for a spin last night and I think it is actually locking and unlocking instead of a 2-3-2-3 shift.
I am going to check the fluid this weekend when I get back in town.
I took it for a spin last night and I think it is actually locking and unlocking instead of a 2-3-2-3 shift.
I am going to check the fluid this weekend when I get back in town.