98 A4 Tranny Shifting Hard
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
98 A4 Tranny Shifting Hard
I've noticed the last couple of times I took the car out it ran great for an hour or so. Then after that, when starting off, it would go from 1st to 2nd with no slip between whatsover. It actually jerks the car (and the wifes neck!). It's also similar in 2nd to 3rd but you don't feel it so bad because you're moving.
I had messed with the shift firmness program with my Hypertech Tuner but have since put it back to stock. I also upgraded to 3.42 gears but that should have nothing to do with it. Especially since it works fine for the first 1-2 hours of driving.
I checked the Tranny Fluid Temp and it was at 203 when it did this. Don't know if that's about an average temp on a relatively cool day.
Anyone else experience something similar or have any suggestions?
Thanks
I had messed with the shift firmness program with my Hypertech Tuner but have since put it back to stock. I also upgraded to 3.42 gears but that should have nothing to do with it. Especially since it works fine for the first 1-2 hours of driving.
I checked the Tranny Fluid Temp and it was at 203 when it did this. Don't know if that's about an average temp on a relatively cool day.
Anyone else experience something similar or have any suggestions?
Thanks
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: 98 A4 Tranny Shifting Hard (Kent1999)
I also upgraded to 3.42 gears but that should have nothing to do with it.
When the PCM "thinks" the transmission is slipping more than normal, it will raise the line pressure to compensate. But since your tranny isn't really slipping (it's your 3.42 upgraded axle ratio that is fooling the PCM into thinking your tranny is slipping) the raise in line pressure is way too much and you get neck jerking shifts.
The Hypertech does not successfully perform gear scaling on a C5. It works great on F bodies.. but not the C5. If you relied solely on the Hypertech to reprog for your 3.42 gears... than this is very possibly the cause of your problems. Although it may have not happened yet, you will also throw an error code (P1870 slip code) and a check engine light.
.
[Modified by Mike Mercury, 7:29 PM 6/21/2003]
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Re: 98 A4 Tranny Shifting Hard (Mike Mercury)
I also upgraded to 3.42 gears but that should have nothing to do with it.
that may have everything to do with it.
that may have everything to do with it.
I haven't seen similar post from others who have upgraded to 3.42's with A4's. And being the car runs great for the first hour or so, didn't think that would be it. We shall see.
Thanks...
Safety Car
Joined: Jun 2003
Posts: 4,640
Likes: 0
From: Sunshine State
Re: 98 A4 Tranny Shifting Hard (78Vette-SA)
Mike Mercury is almost right. I experienced the same problems your having. When your transmission starts shifting hard, I'll guarantee you'll see an 1870 code but I don't think you'll ever see a 'check engine light'. I never did. Do you know how to check codes and clear them? I don't think your driving an hour has anything to do with it, I think it's the road condition, probably going uphill. I could accurately predict 75% of the time when mine would throw a code. I contacted Hypertech and they said their unit would not correct the problem. I had my PCM programmed and the problem disappeared. Hope this helps.
Bob
:flag
Bob
:flag
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Re: 98 A4 Tranny Shifting Hard (Korreck)
Thanks Mike and Korreck, looks like you are both right.
I checked the codes this morning. It has an 0705, which according to my listing is: P0705 Transmission Range Switch Circuit (A/T). And it also has 1870!
Interestingly enough, a couple of weeks ago when it first happened, it did in fact display the Check Engine light. I thought it was related to something else and reset it at the time. I forgot about that. At that time, when I reset the computer with the HPIII, it went away.
Both times that this happened it was raining out and on one or more occasions the traction control had kicked in. This slippage I guess may have set it off.
I have the new computer coming this week. It's programmed for the 3.42's. Hopefully that will clear up the problem.
Thanks again>
:smash: :smash: :smash:
I checked the codes this morning. It has an 0705, which according to my listing is: P0705 Transmission Range Switch Circuit (A/T). And it also has 1870!
Interestingly enough, a couple of weeks ago when it first happened, it did in fact display the Check Engine light. I thought it was related to something else and reset it at the time. I forgot about that. At that time, when I reset the computer with the HPIII, it went away.
Both times that this happened it was raining out and on one or more occasions the traction control had kicked in. This slippage I guess may have set it off.
I have the new computer coming this week. It's programmed for the 3.42's. Hopefully that will clear up the problem.
Thanks again>
:smash: :smash: :smash:
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Team Owner
Joined: Oct 2001
Posts: 46,766
Likes: 5
From: Boynton Beach Florida
St. Jude Donor '07-'12, '20
Re: 98 A4 Tranny Shifting Hard (78Vette-SA)
I had the same exact problem with my A4 going from 2.73 to 3.42 without the proper programming for the gears. Once the programming for the gears was installed no more problem. :D Mike Mercury is absolutely correct. Install the new program and all will be well. :cheers:
Bob
Bob
Drifting
Joined: May 2002
Posts: 1,607
Likes: 1
From: San Francisco CA
Re: 98 A4 Tranny Shifting Hard (78Vette-SA)
After I installed my 3.42’s, I got the 1870 code together with the hard shifting. I had to wait a few days before I was able to get the PCM reprogrammed and found that I could sidestep the problem by keeping the gear selector in ‘3’ instead of ‘D’. There are a number of conditions that have to be met in order for the computer to set the code and this procedure keeps the conditions from being met as one of the conditions is that the lever be in ‘D’.
Team Owner
Joined: Apr 2001
Posts: 54,204
Likes: 180
From: S.W. Ohio. . . . . . NRA Life Member
Re: 98 A4 Tranny Shifting Hard (SFVetteman)
. And being the car runs great for the first hour or so,
If you clear out the codes, it will buy you some time until it happens all over again.
To get the CE light, you would need to drive it for a lengthy time in 4th. Since GM did a major re-write of the PCM program in 2001, I don't know if this holds true for 2000 or earlier C5's.
.
[Modified by Mike Mercury, 11:06 AM 6/22/2003]
Safety Car
Joined: Jul 2002
Posts: 3,874
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From: Fishing Somewhere Cold
St. Jude Donor '11-'12-'13, '15
Re: 98 A4 Tranny Shifting Hard (Mike Mercury)
:iagree:
The slippage condition "or what it thinks is" has to be present for a certain number of start stop cycles for it to throw the code 1870. The first time mine did it the check engine light was also present but when re-set, went away but the code and the resulting max shift pressure came back after a few days without the check engine light. Mine (gears,TC) were installed and LS1 edit for 3:42 gear scaling used and we still later dialed the allowable slippage settings higher to avoid this happening again. I also have a SY3500 which may also have contributed to the detected slippage. This abitrary number will be highest while driving uphill, TC locked and has to be present for a certain amount of time per cycle before setting codes.
The slippage condition "or what it thinks is" has to be present for a certain number of start stop cycles for it to throw the code 1870. The first time mine did it the check engine light was also present but when re-set, went away but the code and the resulting max shift pressure came back after a few days without the check engine light. Mine (gears,TC) were installed and LS1 edit for 3:42 gear scaling used and we still later dialed the allowable slippage settings higher to avoid this happening again. I also have a SY3500 which may also have contributed to the detected slippage. This abitrary number will be highest while driving uphill, TC locked and has to be present for a certain amount of time per cycle before setting codes.
Drifting
Joined: Sep 2002
Posts: 1,529
Likes: 0
From: Lost Angeles CA
St. Jude Donor '03 & '05
Re: 98 A4 Tranny Shifting Hard (78Vette-SA)
you can not reprogram a 98' for 3.42's with the hypertech.
only 3.15's
you need to get it changed with LS1 edit. as far as i know there is no hand held prog. that will adjust for 3.42's in 97-98 C5's ive been looking into it that is part of the reason i havent installed my 3.42's yet.
called hypertech and they do not have a device that will correct for 3.42's in a 97-98. maybe look into a fast chip or LS1 edit but there is now way you changed the program for 3.42's with the hypertech
[Modified by devo, 2:11 PM 6/22/2003]
only 3.15's
you need to get it changed with LS1 edit. as far as i know there is no hand held prog. that will adjust for 3.42's in 97-98 C5's ive been looking into it that is part of the reason i havent installed my 3.42's yet.
called hypertech and they do not have a device that will correct for 3.42's in a 97-98. maybe look into a fast chip or LS1 edit but there is now way you changed the program for 3.42's with the hypertech
[Modified by devo, 2:11 PM 6/22/2003]
Thread Starter
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Re: 98 A4 Tranny Shifting Hard (devo)
you can not reprogram a 98' for 3.42's with the hypertech.
only 3.15's
you need to get it changed with LS1 edit. as far as i know there is no hand held prog. that will adjust for 3.42's in 97-98 C5's ive been looking into it that is part of the reason i havent installed my 3.42's yet.
called hypertech and they do not have a device that will correct for 3.42's in a 97-98. maybe look into a fast chip or LS1 edit but there is now way you changed the program for 3.42's with the hypertech
[Modified by devo, 2:11 PM 6/22/2003]
only 3.15's
you need to get it changed with LS1 edit. as far as i know there is no hand held prog. that will adjust for 3.42's in 97-98 C5's ive been looking into it that is part of the reason i havent installed my 3.42's yet.
called hypertech and they do not have a device that will correct for 3.42's in a 97-98. maybe look into a fast chip or LS1 edit but there is now way you changed the program for 3.42's with the hypertech
[Modified by devo, 2:11 PM 6/22/2003]
Le Mans Master
Joined: Jul 1999
Posts: 5,005
Likes: 38
From: jackson nj
Re: 98 A4 Tranny Shifting Hard (78Vette-SA)
I had a periodic problem with my 98 that sounds similar. If you check the DIC for codes after it starts, I think you will find you are getting a P0748 or P0751 code. If this is the case, have it checked out as it may be a false code but it still makes the shift very, very hard.
Drifting
Joined: Sep 2002
Posts: 1,529
Likes: 0
From: Lost Angeles CA
St. Jude Donor '03 & '05
Re: 98 A4 Tranny Shifting Hard (78Vette-SA)
Thanks for the confirmation. My new computer will be here this week so that should get me squared away. :smash: :smash:
and what prog you used
thanx, Dean :D
