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Discussion Starter · #1 ·
Ok, so I THINK this is an issue, but thought I would ask here incase its supposed to be this way...

My car is an auto trans. When im driving at say 55 and take my foot off the gas to coast it feels like its a manual, I can feel a bit of engine drag slowing me down, but once i tap the brakes my tach drops to its normal idle point and it is like I pushed the clutch in on a manual and my car coasts easier and dosent slow down as quickly as before.

I have been told it might be my torque converter lock-up, but honestly I have no idea how that works at all so I have no clue...

Basically, is this normal or is it something I should worry about? The car has 145000 miles on it, and had a reman Jasper trans put in about 4000 ago...
 

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PCM controls TCC lock/unlock. It looks at speed and gear , and it also monitors the brake switch. In 4th gear running on level road w/steady throttle TCC locks at 45 MPH and releases at 41 MPH or when brake is applied. RPM should drop to about 1100-1200 when you let off the throttle and stay there till speed drops below 12 MPH, should not return to idle speed (550 RPM) till speed is at 0 MPH. TCC control is the same circuit/solenoid for speed & gear control and also brake control. Are you just taping the brake pedal a bit w/o actually activating the brakes to release TC, that would say the electrical dis-engage is working ok. Or do you have to actually engage the brake pads to get the TC disengaged which may piont to mechanical sticking in the TC/tranny side. Has anyone ever changed (tuned) the PCM settings?
 

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Discussion Starter · #3 ·
I don't know if the PCM has been tuned... I know things have been done to the car, but I'm still learning what... It has gears in the back, but I know the PCM was NOT adjusted for them. as it is now, on the interstate at 75-80 per my GPS my speedo says around 100-105mph at about 2300-2500 rpm.

What you explained seem about what it is doing, but due to the gears and PCM not tuned for them, it sounds like it is running right. I'm just noticing it a bit more (The TC Lock/UnLock) due to the vss and PCM thinking the car is going faster than it actually is. at 65MPH (GPS) I let off the gas and the TC is still locked tach drops a little, but not much, I tap the brakes (Not enough to apply pad to rotor friction) and it feels like I pushed in a clutch on a manual which I'm guessing is the PCM unlocking the TC and my tach drops to about 1200 or so. I was wrong earlier when I said down to idle... My bad...

I'm still debating how to solve the PCM adjustment for the gears, I was thinking about going through PCMforless.com, but if it has already been tuned for other things but I don't know it I think I could run the risk of damaging something... (I don't know if it has a different cam or anything like that but if it does and it has been tuned for that I don't want to loose that). I have also thought of going with Tunercat and making the adjustments myself. I know the 1-2 shift is very firm, it jerks your head back when Im not trying to, and if I'm heavy on the throttle it will make the tires bark and bounce your head off the seat rest. but the other shifts are a lot less firm...

My car seems to run a tad rich, so I'm sure a tune by someone who knows what they are doing would help a lot, but not knowing if anything was done to it already I'm a bit scared and hence I'm thinking Tunercat...

Yep, I digressed of the original topic, but I hope the info helps you guys help me. :) Thanks for weathering the ramblings this far.

Tip of the old Stetson...
Mike
 

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If you decide to go the tunercat route, I would make a list of the mods and see if any other members have cars with the same mods. Then have them send you a copy of their tune bin file. It would be a good starting point and all you would have to do is dial it in to your car. There's tuning info on this site. In the sticky threads of pcm section. Also LT1 PCM Tuning - Welcome! has tuning info. Do a web search also.

Changing the rear gear ratio in tunercat is fairly easy.
 

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Discussion Starter · #5 ·
If you decide to go the tunercat route, I would make a list of the mods and see if any other members have cars with the same mods. Then have them send you a copy of their tune bin file. It would be a good starting point and all you would have to do is dial it in to your car. There's tuning info on this site. In the sticky threads of pcm section. Also LT1 PCM Tuning - Welcome! has tuning info. Do a web search also.

Changing the rear gear ratio in tunercat is fairly easy.
Well I ordered a cable from aldl cables today and I have the 30 day tunercat... S I think next week I will be tweeking the rear gear settings. as to other mods, well I dont know if any were tuned into the PCM. I will try using the datamaster scan app or something and recording a log of my car once I get tuner cat running and we will see where it goes from there. as to that link you added, I have that saved in my bookmarks. I have been searching the web and reading everything I can for the last few weeks trying to decide if I want to do this myself, or if I want to send it out to someone else.

Can you guess which way I decided to jump? :werd:
 

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Discussion Starter · #7 ·
You can also use tunercat to read the contents of you pcm then compare it to the stock pcm tune for the 95 A4, which I will post up.
You see, and that's why I love forums with helpful members! Thanks. Cable should be here on Friday and I will hopefully be able to start playing on Monday. would start Saturday but the wife seems to think out anniversary is important... :devil:
 

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Discussion Starter · #8 ·
So with the file you posted, after I compare it with my current tune, can I use your file to tune with or do I still need to buy the file from tunercat?
 

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The file I posted is the stock tuning that came from factory. When you get tunercat, you will have it read the tuning in your pcm. Then you can compare the 2 files and see if any tuning has been done.

However, you will probably still have to post up a list of the mods your car has and ask members to post up a file from one that has the same mods or very similar. YOu can load that tune in your pcm and it will be a good starting point for the fine tuning you will have to do.

When downloading tunercat, even the free trial version, you must pony up 20 bucks for the $EE definition file tunercat needs to read your 95 pcm. The trial version comes with a definition file, but it's for something like a 87 cutlass. The one that comes with the trial version weon't read our lt1 cars.
 
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