Anyone know of any independent shops in St. Louis that know Gen 3 Prii pretty well? Other than Auto Evaluators. I know they’re supposed to be exactly this, and judging by the number of older Prii they had in for service maybe they are. But I went there once and…let’s just say that was all it took for me to learn that I do not trust them to be fair and honest at all. I have been to JAMCO a few times, but they don’t want to touch more than the basics (oil change, tires, brakes, etc) on Prius. Anyway, my wife’s 2012 Prius has almost 130k miles and recently had the shakes on startup. We had it happen once or twice before a couple years ago, but it stopped doing it on its own. The more recent time it happened, I scanned for codes and it showed P0302 (cylinder 2 misfire). So I’m concerned that it needs a thorough EGR & intake cleaning.
A misfire in a cylinder may be related to the spark plug, ignition coil. Have you checked this? Are you far from servicing cars, even "at all"?
You need to pressurise the coolant system and use a bore scope in the spark plug hole for each cylinder and check for leaks. It is possible it could just be the spark plug, and/or coil. You could switch the #2 plug with the #3 or 4 and see if the misfire changed to where it happens. If it does, you can be pretty certain it's a bad plug. At 130,000 miles it's due for a plug change, If it stays at #2, it could be the coil, switch it also. If it stays on #2, you can be pretty certain it's a head gasket failing. Cooler temps out and hot engine can cause moisture in the intake that caused the rattle and sometimes a misfire code. Sorry, can't help you with finding an honest shop....
