22lbChevelle
Member
- Joined
- Jan 14, 2005
- Messages
- 968
Hey I had my 85 year old grandpa make me up 2 of the gnttype.org knock alarms. They are based off of a 555 timer circuit. I've installed one in my Chevelle and one in my Dad's GN and the problem with them is that they work great but wont turn off when he trigger goes off.. Today I removed the 1uF capacitor and they work fine now. I tried bigger capacitors thinking the #6prong on the timer wouldnt get above 2/3V with the 1uF capacitor, but nothing helped. Now get this, when I took the 1uF capacitor out, they both work exactly like they should, turn on and off with a ground signal. My worry is if they work without the capacitor then will it not let the Buick ECM know when there is knock?