Checked it with a timing light at idle. I have R12 pulled. The spec I believe is the same for the 250ohm and 750ohm resistors. I've got a mercedes 103 factory engine manual at work. I was studying up on fixing my low power and hard start. Still giving me greif though. I'm narrowing it down to a likely engine harness problem but I'm going to swap in some injectors and O2 sensor before I try the harness.