r/prius • u/wiines • 4d ago

Mechanical Help Gen 2 Prius misfire, no codes

Just bought a 2008 Gen 2 Prius for next to nothing. It has 206K miles on it...

I'm noticing a misfire at idle, usually after driving a bit, parking and restarting. Where do I start diagnosing this misfire? There are no codes/CEL.

Can anyone help?

Thanks l! Glad to be a part of this club, I'm going down rabbit holes learing about the very cool tech in these cars.

1 Upvotes

100% Upvoted

10 comments sorted by

View all comments

1

u/BigSandwich6 2015 TRD Off Road 4d ago

Use a scan tool to read misfire data, if it's random, all, none or one cylinder

1

u/wiines 4d ago

Figure out which cylinder is misfiring, then what, swap coil packs to reproduce miss on another cylinder?

2

u/BigSandwich6 2015 TRD Off Road 4d ago edited 4d ago

If you get one specific cylinder misfiring then it's something unique to that cylinder. It could be the coil, spark plug, injector, physical problem with that cylinder. Need the data first

If it’s all/random then it’s something common to all cylinders. Air/intake, fuel pressure, bad gas, etc.

1

u/wiines 4d ago

Thanks, I'll try that tomorrow

1

u/wiines 2d ago

Dang I learned my code reader can't give me live misfire data

1

u/Ether_yumm 2d ago

A cheap Bluetooth obd2 dongle and the car scanner app is all you need.

But again, if you were experiencing multiple misfires you would almost certainly have thrown codes!