View Full Version : High RPM miss

Roger Kiefer
09-02-2003, 06:04 PM
I have been fighting a high rpm miss for some time. I changed the ignition box 6al, the pickup coil, the coil, blaster 2, Plug wires, MSD 8.5, spark plugs, rewired all systems and still had the same miss at the same rpm every run. So I took the high rpm chip out of the 2 step and made a pass and miss dissapeared. My question is, do I have a bad 2 step or a bad chip and how can I check to see which one is the problem. I shift at 6800 and go thru at 7000, the chip is new and is 7800

09-02-2003, 11:59 PM
You can remove each module from the two step and try them individually in the ignition to see if they cause a problem or you can check the resistance of the rpm module. The 7800 rpm module should read 6646.6 ohms. Most likely though, you are getting EMI into the two step. Make sure that the harness from the two step is not near any spark plug wires. Also check your magnetic pickup harness that plugs into the MSD Violet/Green wires to make sure it is not near any spark plug wires or the coil wire.

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