2012 Prius v with 260k miles. Six times over the past year when starting up in the morning there is a brief misfire for about 5 seconds. No check engine light triggered. Then today, every time I am at idle or start the car I get a bad misfire for about 10 seconds then it goes away. Check engine light was triggered today (misfire cylinder 2). Any suggestions on where to start? I've never ha a misfire that goes away after a few seconds. Once it goes away everything runs fine.
Everything looks OK. I was hoping this was a common issue, but if not I'll start with plugs and wires and keep working until it's solved.
at 260k, i don't know what is common, but someone else may jump in with better advice. are you up to date on all maintenance?
What is your history with the car? Original owner? If not, how long have you had it? What maintenance has been done: only by the book or some other things(PCV valve, egr pipe, etc)? Burning any oil? Consuming any coolant? With the misfire is there any engine hesitation? Keep us posted
It sounds like his engine is already clapping for him. Have you tried shifting components to another cylinder to see if the misfire follows the components?
Good one^ In all seriousness, my sister owns a 2010 Prius and she recently had a bad misfire on cylinder one. The whole car would violently shake when it was first stated. It was awful! Anyway, after changing the spark plugs (they were already new and we didn't know it) no difference noted. So she got on Amazon and orderd a new coil pack and slapped it on cylinder one and it's been smooth since!
New plugs and coil, same problem. The oil and coolant look OK. Any other ideas before I have to transfer my entire 401k to the dealership?
Minimal maintenance was done on the car before I got it a year ago at 240k miles. Not burning any oil or consuming coolant. Engine hesitates and car rumbles for about 5-10 seconds, then it's perfectly smooth until the engine stops again.
This will tell you the next steps. If clogged or heavy deposits are found, I would then begin the intake manifold and egr valve cleaning. While there and removing the manifold, also worth doing the PCV valve, throttle body cleaning along with MAF sensor cleaning. If no deposits (highly unlikely), look to the fuel delivery system (low pressure on fuel delivery can also lead to a problem). Keep us posted .
Before you start throwing .... Have inspected fuel injection pulse.....coil pack's...... Compression..... Maf sensor Throttle body stepper motor reading at idle...is it dirty....yes...no If yes entire Egr system need inspection Check spark plug gap Using specific tool to look inside combustion chambers are the burning of fuel is up to the specs...or shows carbon build If all of this check good go and check O2 sensors at idle and driving...partial throttle and full throttle readings...... Once you have this all .....i would like pictures i will try at my best to give more definite answer Posted via the PriusChat mobile app.
Update: I noticed today that the coolant level is down about 1" after driving the car 100 miles. Taking it in to test for a blown head gasket next week.
Any chance of an update regarding confirmation/cause? We're early days with this high mileage Gen 3 head gasket failure pattern. Any data we can get helps, thanks.
