Hey PC, my 2010 prius has 192k miles and has an intermittent misfire. About 1 in 5 times that the engine turns on it misfires so bad that it sounds like the engine is blown and about to die. The other 4 times out of 5 it runs smooth from idle to 2500rpm it runs like new. All I have to work with is a code for cylinder 2 misfire. Oil is at good level and looks good, coolant is at good level and looks good. Any helpful advice before I go down the diagnostic list? Posted via the PriusChat mobile app.
Injector or coil. How old plugs? That's the cheapest to change first. Could swap coils to see if it changes cylinder. Posted via the PriusChat mobile app.
Start with plugs and the coil. Clean EGR cooler, piping, and intake manifold. If that doesn’t cure it, then run a compression test.
The easiest part of the EGR circuit to remove and check is the "pipe", watch @NutzAboutBolts video #16 here: Nutz About Bolts Prius Maintenance Videos | PriusChat If you've not heard of EGR, never touched it before, with 192K miles it it'll very likely be getting pretty clogged. If so, from there I'd proceed to a full EGR cleaning, intake manifold cleaning and OCC install. There's videos on those too, same location.
I changed all 4 spark plugs and it seemed to run a bit better but problem was not resolved, then I followed instructions from the video above on cleaning the EGR and that made a world of a difference. About 8k miles driven since then it only misfires for about 5 seconds on a cold start. Posted via the PriusChat mobile app.
Not quite out of the woods? Did you clean the intake manifold too? There's EGR passages in there too. Video on that at the same location. Quote from @Ragingfit : Well we're not out of the woods yet, but uh, certainly feeling ok about it... Starting to like the woods.
I am still saying head gasket is leaking into the combustion Chambers Posted via the PriusChat mobile app.
I suppose it could be possible but no other symptoms of head gasket failure, time will tell. Posted via the PriusChat mobile app.
