I had a bad experience with the Performance Products ASR defeat switch. Poor instructions that did not match the wiring in my E-500. Had a top notch mechanic who works on all the E-500's in the Seattle area..he even talked with their tech dpt. No luck. I have to give credit to Perofrmance Products as they gave me a full refund,,although I was out the labor costs. Have since had the Renn-tech ASR defeat installed which was a piece of cake & works great. Highly recommend you spend the extra money for the Renntech version. Good Luck