Hi everyone, was hoping I could get some help with my Prius. The ole girl has a really bad shudder/vibration at idle that I'm 99% sure is caused by a misfire. There is a lot of information out there on this and, I have done the "unplug each coil" diagnostic. The weird part is, it doesn't matter which coil I unplug, doing it clears up the misfire, that's where I'm getting super confused. Am I missing something? Or does anybody have any ideas? (It has been brought to a dealer and I keep getting sent away told "We're not sure what the problem is, we'll look into it and give you a call" and of course I never do get a call) Thanks a ton everyone!
Is it constant or does it stop after a couple of seconds? Anything trigger it on or off? I know the electric steering sensors can cause quite a shudder in the steering wheel. Are you simply unplugging the connectors at each coil or swapping a new coil in place of each one?
Thank you very much for your response! The shudder isn't in the steering wheel but in the motor, the thing jerks around like a bucking bronco. The codes which I apparently forgot to mention, are a misfire in all four cylinders. The coils were replaced around 3 month ago in an attempt by the former owner to clear it up along with new spark plugs. As for diagnosing, we're just disconnecting one at a time, the shudder clears up no matter which one we disconnect. As for the question about it being constant, it is, it doesn't matter if we give it some gas, let it run, nothing makes it go away. The only thing we've been able to do to get it to clear up is to disconnect the battery. When reconnected, on the first start up, it will run right for a max of 5 seconds. Seems I forgot quite a bit of info in my first post and I apologize.
Try mixing them around, coil 1 to 4, 4 to 3, etc. Where did the coils come from, are they Toyota brand? Try cleaning the coil wire plugs with contact cleaner (same with the wiring.) What brand plugs? Do you have the trouble codes? The problem clears when you d/c the 12v battery because you are erasing the codes in the ecm. You might also have a problem with the ecm. Ericbecky (his forum name) is in Madison and probably could help you. EV Powers Hybrid Battery Service and Repair Your Hybrid Battery Hero Madison, WI [email protected] six/oh/eight-729-4082 Or contact forum member ChapmanF. He's pretty good, too.