Got the Prefix Race controller for the GenV back in March. Overall, love it especially the decel pop. Upon installation and after performing the throttle relearn procedure, it idled around 750 rpm similar to stock. After about 100+/- miles, it idles at 1K RPM. I contacted Prefix via email. The response given is that it’s intentional in order to distinguish between the stock PCM and Race Controller. I called Prefix…same person answered that responded to my email. However, he asked if performed the throttle relearn procedure, I did. He said that was odd, would look into it and get back to me. That was two months ago.
Anyone experience this idle issue with the Prefix Race Controller. Performed another relearn but high idle still persists. I’d send it back for diagnostic but can’t get anyone @ Prefix to return my calls.
When Vipers were new, they idled at 1000 RPMs for the first 500-750 miles. After that the idle dropped down to about 750. I believe once you installed the new controller and did the throttle relearn the computer was basically acting as if the car was new. Put some miles on it and it should come back down to 750.
Thanks George but that’s not what Prefix told me when I last chatted with them. Fellow Viper owner nearby installed his and no 1K RPM idle. Possible Prefix changed it over time and removed the 1K RPM. Nonetheless, Prefix gave me different information. However, Prefix doesn’t respond. At best I get the same person that gives me a different answer every time I reach out but never follows up. Been unable to reach anyone since April.
This reply was modified 8 months, 3 weeks ago by ViperTony.
Tony who did the throttle relearn and how did they do it? My understanding is it can only be done correctly by a dodge dealership with the Dodge computer system (forgot its name) this could be the problem.
Verified with Preifx that there’s no 1k RPM idle setting, in any form, on the race controller. Not part of the calibration. Controller is going back to Prefix for diagnostics. Scott is very knowledgeable and glad he’s still with Prefix supporting Viper!
Scott @ Prefix resolved the high idle issue, the “green engine high idle” setting was inadvertently enabled. No, the race controllers are NOT programmed to idle high. And the controllers don’t idle high for 1K miles, etc. Scott is the best!
I had the same problem with the controller from prefix. You need to send it back for them to “fix” the idle probem. It took them 2 returns to get it right. Also have them turn the gurgle sound on deceleration. Prefix has some QC issues.