My auto mechanic and I, after extensive diagnosis, have confirmed that the Pulse mileage/route tracking device that Metromile car insurance had me plug into the computer port of my 1998 Toyota Corolla LE is failing or has failed, and this caused a potentially disastrous situation to develop w/my car engine. When starting the engine from cold, it would cause repeated misfires, causing the rpms to drop quickly, then surge up, before settling into the proper cold idle speed. This would repeat itself every few seconds until the engine warmed up completely (usually about 10 minutes). When in gear, the car would buck violently, putting repeated, extreme stress on the drive train; but even when in neutral gear, two mechanics have told me it could easily destroy my crankshaft bearings and/or other parts of the drive train. We have now tested this five times briefly in neutral gear. When we plug the pulse device in the problem occurs immediately. When we remove the device the problem goes away. We can also insert the mechanic's diagnostic device into the computer port and everything works fine. The new "Pulse" device was received as a replacement for the old one I had been using, that had worked fine, and was first inserted into the computer port on 8/9/21. So it worked fine for about a month. Supposedly the only difference between the old and new devices is that the new one uses 5G instead of 4G to receive and transmit data.

- Spokane, WA, USA