I have a 2017 prius with about 42k miles on it. My wife drove it through a puddle about a couple of months ago. The engine light came on. I was traveling so I asked her to park the prius and drive the other car. When I got back 10 days later I could feel moisture in the floor mats and the check engine light was on. I started the car and drove it about 50 miles and the engine light went away. However, I could feel a shudder/shake everytime the engine would kick in especially if you keep a light foot on the gas.. With a light foot it is a sustained shake. If you accelerate hard, the shake goes away. There is zero shake whe the car is running on electric motor. I have also notices that the shake is minimal when the car is cold. The translation from ICE to electric and back is smooth. I took the car to a local garage. The plugs got replaced, coils are also fine, air filter replaced. They even opened the inspected the transmission damper but no issues were detected. There are no error messages when you put the scanner in. Any idea what might be the cause? Thanks
Check the fuel trims and temperature sensors for proper operations. The CEL should be in your scan tool history, see what code was initially tripped - that may give you a clue to what's going on. Or you may just have a bad tank of fuel - dump some injection cleaner in the tank and see what happens.
The shaking at moderate load, not at heavy load and not at idle, can be a strong suggestion to clean the small EGR passages found in the intake manifold.
Steady no visible loss over the last 2 months Steady level. Have observed no reduction.. tx Coolant level steady and no reduction observed.
A puddle ? carpet was wet? is the carpet dry now? 2011 Throwing Codes After Driving Through Puddle | PriusChat
Thank you. Have checked plugs, coils and all relevant sensors still the same. As a last resort, am have the ecm looked at for potential transistor misbehavior. Will update ASAP. Thank you for your inputs
Adeendum: The shaking clearly is on account of engine misfiring at low rpms.. unfortunately it is at the sweet spot where all the gas savings are. If you keep rpms high misfiring disappears ....will update soon. Thanks again
If you are able to post and Diagnostic Trouble Codes specific to your Prius issues, that could help us reading your thread understand, why the puddle and wet carpeting observations lead to the misfire at optimal RPM and disappearing at higher RPM. If it's extra work or worry, please don't feel obligated in any way. And thank you for updating your thread with what you have already learned.
Try cleaning the intake manifold? Note, in the attached, Toyota doesn't make any mention of of torque for throttle body hold-down nuts/bolts. FWIW, for 3rd gen the value is 7 lb/ft.
