Engine rattling / shaking after filling from spare fuel tank - P3191

You might have gunked up the fuel filter which - as far as I know - is unfortunately in the tank. Of course, one could just say "check the fuel pressure," but that's a stupid rabbit hole all its own. Whoever designs these kinds of things should be tortured and then shot. Slowly. You know what? Just give me a GDMF schrader valve for checking fuel pressure! And an nice, normal, inline fuel filter!

So by all means, bomb it with some fuel system cleaners for a while. Chevron techron and seafaom are my faves. And a new set of plugs is not very expensive nor very complicated so I'd never say not to...

 

OK, I skipped to the end of this thread so may be covering old ground. Do you have no other codes pointing to a misfire? 3191 can be random - something burped and it goes off. If you had a code pointing to a cylinder, you can just swap around plugs and injectors to see when the problem moves with the swap.

You also mentioned it being smoother in Park or vice versa. That can simply mean your gas engine is not running. Does it shake as soon as it turns Ready, or 6 seconds or so later, when the ICE starts up? FYI, I'm dealing with a one-off 3191 that I'm pretty sure was caused by coolant leaking into the intake manifold through the throttle body. I've read of that leak getting worse and burning up plugs. But, you'd probably be overheating as well, as I am.

 

Late lurker here... since this started with the addition of old fuel, let me suggest that there may have been enough dirt/contaminants in the old fuel which made it past the fuel filter that the injectors are possibly clogged.

Solution is to get rid of as much of the old fuel as possible, replace with good premium fuel and fuel injector cleaner; that MAY dissolve enough gunk to resolve the issue. It's a maybe.

If that fails, then the injectors may need replacement. Ouch.

 

Hint: if you want the engine to ALWAYS run, start the engine, turn on the AC, set it to min temp, and press the MAX button. Normally the ICE shuts off when it gets to operating temperature, then cycles as the A/C demands... the MAX button tells the engine not to turn off.

This may speed the process to get any 'bad' fuel out of the system once you have "good" fuel in the tank.

Good luck with the procedures...

 

Injectors aren't a big deal. Easy to replace, not that expensive. I bought a set of used ones off Ebay for, IIRC, $40. Literally, the ICE never runs, after warming up, unless it has to, like when you're driving or parked/idling with AC on. I expect it stopped when you put the car in Neutral. You can always pop the hood and see - it's the left side of the engine compartment. Injectors, plugs, coils, dirty throttle body - those are the main culprits.

 

No, you just remove the air cleaner. Some instructions say to bleed the fuel line pressure, but I didn't. Just lift it off, some fuel will squirt out, not much. Then, the injectors just pull out. I can replace them all easily in 30 minutes, and not even get dirty.

Most new cars won't shift out of park without the key in the ignition - or by depressing a shift lock that's usually "hidden" somewhere around the shifter, like under a pop up tab on the console, or under the ashtray, something like that. I forget if the Prius has a shift lock.

 

search this thread

2001, Engine Vibration (missing badly), Flashing CEL

page 3 has the way I preasure tested the fuel line

 

JP, please keep us updated as to what you find & how you (eventually) resolve your problem.

My story: I decided to clean all the surface dirt off the engine of my '03 Prius this weekend (lots of dust & grime). Turned on the engine, opened the hood, then hosed off the engine while the engine was running. Did this early in the run, before the engine got really warm. Somehow, some water got somewhere it shouldn't have, and the engine began to run rough. No fault codes... and a 'clicking' sound that made me suspect the oil level was low. Turned engine off; checked oil level; it was fine. Restarted; let the engine run for about 5 minutes in Park, turned it off, then restarted. The ICE ran smoothly then. So it doesn't take much water to cause the engine to misbehave.

 

The air intake is just behind R headlight, need to plug that before spraying with engine off, then should be ok