I was just looking into the procedure to replacing the ISC or stepper motor, which I plan on doing tomorrow, and in the manual all I can find are testing procedures. Is there anything that needs to be done other than taking out the old one and putting in the new one? I thought somewhere I read about also resetting the BISS somehow as well.
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Stepper motor replacement
- Thread starterdeez
- Start date
turbowop
Well-known member
Just pull the old one off and install the new one. I don't know if it's necessary or not but I always go through the BISS/idle adjustment procedure just to zero the ISC in its range when I pull mine off for whatever reason.
atc250r
Staff member
What wop said.
fivestardsm
Well-known member
Quoting deez:
I was just looking into the procedure to replacing the ISC or stepper motor, which I plan on doing tomorrow, and in the manual all I can find are testing procedures. Is there anything that needs to be done other than taking out the old one and putting in the new one? I thought somewhere I read about also resetting the BISS somehow as well.
The reason that people say that you need to reset the biss, is because most people will screw with it to try and smooth thier idle out. Just check to make sure your idle is at around 800 - 1100 RPM. I think that factory setting is 850 or 950 RPM, but some like it a little higher.
I was just looking into the procedure to replacing the ISC or stepper motor, which I plan on doing tomorrow, and in the manual all I can find are testing procedures. Is there anything that needs to be done other than taking out the old one and putting in the new one? I thought somewhere I read about also resetting the BISS somehow as well.
The reason that people say that you need to reset the biss, is because most people will screw with it to try and smooth thier idle out. Just check to make sure your idle is at around 800 - 1100 RPM. I think that factory setting is 850 or 950 RPM, but some like it a little higher.
turbowop
Well-known member
Regardless of what you set the idle to via the BISS, the ecu will control the idle at whatever it's set for within the eprom chip. The BISS needs to be set to whatever idle speed the chip is setup for. Trying to adjust it up or down is useless, as you're just fighting with the ecu and is a good way to cause idle surge.
toybreaker
iconoclast
- Joined
- Apr 30, 2006
- Messages
- 3,581
What they all said. /ubbthreads/images/graemlins/smile.gif
If this is a new iac unit just bolt it in, reset the shitarree as per the v-faq, and you're good to go. Take your time, do it right, and the results are very satisfying. A logger really speeds up the proccess, and allows you to verify the iac command and control and the iac operation itself are up to spec.
For a quick post repair operational check, after you're done, give the steering a small turn, and watch for a ~10 count increase in the iac count, and watch for an idle rpm sag.
If this is a used iac you're installing, you must check the coil resistances before allowing the used iac within 10 feet of your car!
Failure to do so may result in a fragged ecu/collaterall damage if one of the coils is shorted.
If this is a new iac unit just bolt it in, reset the shitarree as per the v-faq, and you're good to go. Take your time, do it right, and the results are very satisfying. A logger really speeds up the proccess, and allows you to verify the iac command and control and the iac operation itself are up to spec.
For a quick post repair operational check, after you're done, give the steering a small turn, and watch for a ~10 count increase in the iac count, and watch for an idle rpm sag.
If this is a used iac you're installing, you must check the coil resistances before allowing the used iac within 10 feet of your car!
Failure to do so may result in a fragged ecu/collaterall damage if one of the coils is shorted.
