about how many grounds can be checked and cleaned and which ones are culprits for messing with pcm thanks

 

Rather then checking and cleaning grounds, I found it was easier to just put on new ones. I put a battery cable from battery neg to a bolt through the body close to the battery. I put another new cable from the motor to the body close to the original strap found near the coil. Buy these cables at auto parts stores. Use an inside tooth washer on both ends to help bite into the metal when tightening. I also suggest using chemical contact spray to help protect your new ground connections.
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