Impala 3.8L transmission ECM relearn

[Bandit303]

Does anyone know if the 2000-2005 Impala's ECM for the transmission can be reset by using a combination of turning the ignition (ACC) on and off in combination with another action?
My Impala just started to bog in 1st-to-2nd and 2nd-to-3rd recently after disabling the 160 Km/H speedometer limiter.

[wafrederick]

You have to take it to someone that has GM's factory scan tool,Tech 2 and an AC Delco program on a pentium 4 computer.This is the only way to do this.The 2005 and up are differant,that is a CAN(Contolled Area Network) attachment on the Tech 2 which is needed.

[BNaylor]

Your profile indicates you have a 2003 Impala. This doesn't always work but you can try disconnecting the battery negative cable for several hours or overnight in most GM cars with the SII 3800 engine. It has been known to clear the adaptive shift information (TAPS) stored in the PCM module and allow a relearn. Otherwise, it will require a visit to a GM dealer with a Tech II scan tool.

The question I have is how did you disable the speed limiter?

And welcome to AF.

[impalalover]

Originally Posted by BNaylor

Your profile indicates you have a 2003 Impala. This doesn't always work but you can try disconnecting the battery negative cable for several hours or overnight in most GM cars with the SII 3800 engine. It has been known to clear the adaptive shift information (TAPS) stored in the PCM module and allow a relearn. Otherwise, it will require a visit to a GM dealer with a Tech II scan tool.

The question I have is how did you disable the speed limiter?

And welcome to AF.

i unhooked my battery in my impala because of abnormal shifting.brought her to the dealer they can fix or find the problem because she is not throwing any codes ,even driving with the scanner plugged in,it won't slip,like she was doing,reving up at the start and banging into gear,then changing fron 1st,2nd 3rd and 4th before 30 -40 km's,turn off the car and she is fine for another while,can't get her to do it when the dealer is open to bring it there so they can duplicate it,because of no code showing they think i'm nuts because after 10 or so appointments and 10 different techs driving her she works fine,i did unhook the battery overnight so far so good but i find the car is not rolling per say as good free rolling when driving now,feels like you are driving with your foot on the brake or a sticky brake in which i don't have,she just do'nt feel as free rolling like she did,can anyone anwser why this is happening now

[impalalover]

Originally Posted by impalalover

i unhooked my battery in my impala because of abnormal shifting.brought her to the dealer they can fix or find the problem because she is not throwing any codes ,even driving with the scanner plugged in,it won't slip,like she was doing,reving up at the start and banging into gear,then changing fron 1st,2nd 3rd and 4th before 30 -40 km's,turn off the car and she is fine for another while,can't get her to do it when the dealer is open to bring it there so they can duplicate it,because of no code showing they think i'm nuts because after 10 or so appointments and 10 different techs driving her she works fine,i did unhook the battery overnight so far so good but i find the car is not rolling per say as good free rolling when driving now,feels like you are driving with your foot on the brake or a sticky brake in which i don't have,she just do'nt feel as free rolling like she did,can anyone anwser why this is happening now

ya where is the speed limiter and how do u unhook it,what happens when you unhook it,more top end or what

[echokapp]

I just replaced my 2000 Impala 3800 PCM with high performance one, from the on-line web site "3800performance.com. I must say, I just replaced the entire exhaust system with a high performance one, starting from the downpipe w/flex 3 1/2 all the way back and addedd the additional the dual exhaust. Of course I added the K&N cold air intake as well. WOW, power, power, power.. Then I installed the high performance PCM and WOW, my idle speeds came down, my fuel mileage improved, my shift RPM's are more in turn with the overall high performance package now.
Anyway, Everything worked, lights, horn, windows, after the installed the new PCM, but the engine did not start.
You need to retrain the PCM.. Don't worry about waiting hour for the battery disconnect, I didn't. Disconnect, reconnected.
Try this:

Regarding the replacement of a 2000 Impala 3800 PCM. Here what worked for me.
Note: Never do anything to the PCM until the negative side the of battery is disconnected.
1. Install the PCM with the negative side of the battery disconnected.
2. Once the PCM is in place, connect the negative battery.
3. First attempt at starting the engine:
a. If it starts, great.. good job.
b. If it does not start:
1. Note if the lights, windows, horn, radio, and listen for the very faint sound of the electronic fuel pump engages (approx for 2 -3 seconds).
2. The SECURITY and the BATTERY icon should be alternating in the COMM window.
c. If all the electronic work, but the engine does not start, retrain the PassLock system.
4. Retaining the PassLock system:
a. Ensure the battery is well charged, you'll need it. If it isn't put a battery charger on it.
b. Turn the key as if you were going to start the engine and let go. Leaving the key in the on position.
1. Watch the SECURITY and the BATTERY icon flash on and off, alternating between the two.
2. Do not turn the key off, leave it alone, in the ON position.
3. After approx 10 minutes, the SECURITY and the BATTERY icon message with stop alternating.
c. Repeat set 4.b. two more times. Each time will take approx 10 minutes.
d, After the 3rd retaining cycle, BINGO, the engine will start.

5. If the engine fails to start after performing the above steps, try this..
a. Disconnect the negative side of the battery.
b. Disconnect the positive side of the battery.
c. With both sides of the battery disconnected from the battery, touch the two disconnected battery cables together.
d. Check to ensure the PCM cables are connected properly and firmly in place.
e. Connect the positive side cable to the positive side of the battery.
f. Connect the negative side cable to the negative side of the battery.

6. Now repeat Passlock system retraining steps in item # 4 above.

Enjoy...opcorn: