A4 Tech Challenge-need Help!!
Thread Starter
Instructor
Joined: Jun 2004
Posts: 153
Likes: 0
From: JACKSONVILLE FL
A4 Tech Challenge-need Help!!
I swapped my 98 a4 for a 03 a4 due to the fact i had to replace a bellhousing and torque tube....good time to update tranny. Before i installed the tranny i had hp tran shop look at and they said looked good so they replaced a band and filter. while they were in there i had them install billit servo, oversize.490 valve for pump, put shift kit in and i had them remove ball from input shaft. in addition i put in 3000 vigilante converter.
PROBLEM: CAR DRIVES GREAT HAVE 15 MILES ON THE CHANGE. AROUND 50 MILES AND HOUR AFTER DRIVING A FEW MILES STEADY THE TRANS MAKES A CHANGE AND STARTS SLIPPING IN 4TH. IN ADDITION WHEN YOU SLOW DOWN IT BANGS 2ND AND 1ST DOWNSHIFTING AND THE SAME IF YOU TAKE OFF AGAIN-HARD 1ST AND 2ND SHIFT AND NO 4TH LOCKUP. IF YOU STOP CAR AND SHUT OFF AND START BACK IT DRIVES GREAT UNTIL YOU GET AROUND 50 MPH STEADY FOR LONG PERIOD....THOUGHT ....MAYBE TC APPLIED VALVE IN VB. THANKS IN ADVANCE.
PROBLEM: CAR DRIVES GREAT HAVE 15 MILES ON THE CHANGE. AROUND 50 MILES AND HOUR AFTER DRIVING A FEW MILES STEADY THE TRANS MAKES A CHANGE AND STARTS SLIPPING IN 4TH. IN ADDITION WHEN YOU SLOW DOWN IT BANGS 2ND AND 1ST DOWNSHIFTING AND THE SAME IF YOU TAKE OFF AGAIN-HARD 1ST AND 2ND SHIFT AND NO 4TH LOCKUP. IF YOU STOP CAR AND SHUT OFF AND START BACK IT DRIVES GREAT UNTIL YOU GET AROUND 50 MPH STEADY FOR LONG PERIOD....THOUGHT ....MAYBE TC APPLIED VALVE IN VB. THANKS IN ADVANCE.
Le Mans Master
Joined: Nov 2002
Posts: 7,179
Likes: 2
From: Charlotte, NC
Originally Posted by ANTHONYCORVETTE
I swapped my 98 a4 for a 03 a4 due to the fact i had to replace a bellhousing and torque tube....good time to update tranny. Before i installed the tranny i had hp tran shop look at and they said looked good so they replaced a band and filter. while they were in there i had them install billit servo, oversize.490 valve for pump, put shift kit in and i had them remove ball from input shaft. in addition i put in 3000 vigilante converter.
PROBLEM: CAR DRIVES GREAT HAVE 15 MILES ON THE CHANGE. AROUND 50 MILES AND HOUR AFTER DRIVING A FEW MILES STEADY THE TRANS MAKES A CHANGE AND STARTS SLIPPING IN 4TH. IN ADDITION WHEN YOU SLOW DOWN IT BANGS 2ND AND 1ST DOWNSHIFTING AND THE SAME IF YOU TAKE OFF AGAIN-HARD 1ST AND 2ND SHIFT AND NO 4TH LOCKUP. IF YOU STOP CAR AND SHUT OFF AND START BACK IT DRIVES GREAT UNTIL YOU GET AROUND 50 MPH STEADY FOR LONG PERIOD....THOUGHT ....MAYBE TC APPLIED VALVE IN VB. THANKS IN ADVANCE.
PROBLEM: CAR DRIVES GREAT HAVE 15 MILES ON THE CHANGE. AROUND 50 MILES AND HOUR AFTER DRIVING A FEW MILES STEADY THE TRANS MAKES A CHANGE AND STARTS SLIPPING IN 4TH. IN ADDITION WHEN YOU SLOW DOWN IT BANGS 2ND AND 1ST DOWNSHIFTING AND THE SAME IF YOU TAKE OFF AGAIN-HARD 1ST AND 2ND SHIFT AND NO 4TH LOCKUP. IF YOU STOP CAR AND SHUT OFF AND START BACK IT DRIVES GREAT UNTIL YOU GET AROUND 50 MPH STEADY FOR LONG PERIOD....THOUGHT ....MAYBE TC APPLIED VALVE IN VB. THANKS IN ADVANCE.
I'm thinking too is the trans really slipping or is the converter just not locking up in 4th?
Either way I would talk to the trans shop that did the work.
-=Rick
Safety Car
Joined: Jul 2002
Posts: 3,874
Likes: 0
From: Fishing Somewhere Cold
St. Jude Donor '11-'12-'13, '15
Check your codes...sounds like P1870...but you don't mention any check engine light being on. It could be just because of the amount of slip the PCM is sensing due to the new TC. When I installed my SY3500 I had same issue and had the parameters for sensing slip and setting that code widened in my PCM. No probs. at all since that.
Thread Starter
Instructor
Joined: Jun 2004
Posts: 153
Likes: 0
From: JACKSONVILLE FL
When the trans started to slip @ around 50 mph it kicked the 1870 code. I had the trans shop place a shift kit that was suppossed to help with controlling the 1870 code(boost valve). Is there a tc silonoid or applied valve that are for controlling this action. It seems strange that it happens only @ 50 for a steady period of time..the tran shop does not have an idea...yet...any thoughts 
Le Mans Master
Joined: Jan 2000
Posts: 6,725
Likes: 0
From: South Bend IN
Originally Posted by sweetcharity
Check your codes...sounds like P1870...but you don't mention any check engine light being on. It could be just because of the amount of slip the PCM is sensing due to the new TC. When I installed my SY3500 I had same issue and had the parameters for sensing slip and setting that code widened in my PCM. No probs. at all since that.
That sure sounds like P1870!! 
You'll have to have the slippage compensated for in your programing. Don't drive it much until you do because it will eat up that torque convertor in a hurry. In the meantime drive it in 3rd as it won't allow it to lockup and trip the p1870.
Last edited by Dave00C5; Jan 31, 2005 at 09:49 AM.
Safety Car
Joined: Jul 2002
Posts: 3,874
Likes: 0
From: Fishing Somewhere Cold
St. Jude Donor '11-'12-'13, '15
Originally Posted by ANTHONYCORVETTE
When the trans started to slip @ around 50 mph it kicked the 1870 code. I had the trans shop place a shift kit that was suppossed to help with controlling the 1870 code(boost valve). Is there a tc silonoid or applied valve that are for controlling this action. It seems strange that it happens only @ 50 for a steady period of time..the tran shop does not have an idea...yet...any thoughts
Thread Starter
Instructor
Joined: Jun 2004
Posts: 153
Likes: 0
From: JACKSONVILLE FL
thanks for the advice but when it trips the code does it change the parameters for the tranny. when you are driving along @ 50 in lockup mode for a length of time 4-5 miles steady it instantly starts slipping and when you slow down it bangs 2nd and 1st on the downshift and hits hard on 1st 2nd upshift. when you stop shut off car and re start it acts fine again....until 50 mph steady. and yes the 2nd time the check engine light came on. I cleared the 1870 and the light went off and ok again until 50mph steady....ANY THOUGHTS ON THIS...DOES WIDENING THE 1870 PARAMETERS CHANGE ANYTHING....WHAT IS TRIPPING THE TRANSMISSION CHANGE
Le Mans Master
Joined: Nov 2002
Posts: 7,179
Likes: 2
From: Charlotte, NC
Originally Posted by ANTHONYCORVETTE
thanks for the advice but when it trips the code does it change the parameters for the tranny. when you are driving along @ 50 in lockup mode for a length of time 4-5 miles steady it instantly starts slipping and when you slow down it bangs 2nd and 1st on the downshift and hits hard on 1st 2nd upshift. when you stop shut off car and re start it acts fine again....until 50 mph steady. and yes the 2nd time the check engine light came on. I cleared the 1870 and the light went off and ok again until 50mph steady....ANY THOUGHTS ON THIS...DOES WIDENING THE 1870 PARAMETERS CHANGE ANYTHING....WHAT IS TRIPPING THE TRANSMISSION CHANGE
-=Rick
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
2027 Corvette vs The World: Every Model vs Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
Safety Car
Joined: Jul 2002
Posts: 3,874
Likes: 0
From: Fishing Somewhere Cold
St. Jude Donor '11-'12-'13, '15
Yes to the above.....thats exactly why it is banging the 1-2 shifts. The line pressure is automatically set to max to counteract any slippage in an attempt to save your tranny when the code P1870 is set.....TAKE IT BACK TO THE TUNER AND HAVE THE PARAMETERS WIDENED!!! When it happened to me and I felt the shift, I about crapped my pants!! It is a little unsettleing to say the least!
(This is assuming that there are no other problems going on. If your tranny was slipping badly there would be some high temps associated with that. Sooo ruling out a bad transmission the above is the way to go)
(This is assuming that there are no other problems going on. If your tranny was slipping badly there would be some high temps associated with that. Sooo ruling out a bad transmission the above is the way to go)
Last edited by sweetcharity; Jan 31, 2005 at 08:19 PM.
Thread Starter
Instructor
Joined: Jun 2004
Posts: 153
Likes: 0
From: JACKSONVILLE FL
thanks for all the help!! the trans temp seems to stay between 185 and 195 max. do you recommend LS edit----not sure what the software costs but the the closest tuner is the other end of florida. Is Ls edit a good investment...thanks for all the help again
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
LS1edit or HPtuners are both great investments, you can tweak what ever you want and they will both retain their resale value incase you sell your car.
Personally I prefer HP Tuner because it comes with it's own scanning software, if you buy LS1 edit then you'll also need to buy a scanning software like Autotap, the other benefit to HP tuner is it is locked to a model year so if you buy the software for a 98 Corvette then you can use it on any 98 Corvette but if you buy LS1 edit it's locked to a VIN and you can only use it on those VIN's.
Personally I prefer HP Tuner because it comes with it's own scanning software, if you buy LS1 edit then you'll also need to buy a scanning software like Autotap, the other benefit to HP tuner is it is locked to a model year so if you buy the software for a 98 Corvette then you can use it on any 98 Corvette but if you buy LS1 edit it's locked to a VIN and you can only use it on those VIN's.
