Jumped from 32 MPG to 56.6MPG - Heres How

Robert perhaps a separate post "how do you check compression" but I don't recall ever hearing anyone talk about checking that on a Prius.

 

We had the sparks plugs replaced on our 2010 Prius when it had well over 100,000 miles. The plugs, Nippendso Iridium, look like they
could go another 100,000 miles easily. No carbon buildup at all. We mainly use 87 octane (10% ethanol) at Costco with no problems. Infact I have used the same gas in our 2014 Volt, yes I know it requires premium, with no problems and still got over 40 mpg's just on gas, regular Costco gas at that.

Who knows how other countries refine their crude oil in gasoline and distillates. US and Europe are probably number one in quality refined
petroleum products.

 

hmm...my mpg is still good. But after reading this, i guess it's time to pour some injector cleaners to my gas. Hopefully that will help even just a bit.

 

I'm guessing nobody suggested the injectors as the culprit because it's such a rare problem in the US and Canada. I've never had injector issues in the hundreds of thousands of miles I've driven, and I gas up at whatever station is cheapest; usually Arco.

BTW, Arco fuel is now Top Tier rated, and meets the same standards as Shell, Chevron and Texaco. Funny how their fuels are 30 cents per gallon more just across from the Arco station.

 

I'm seriously thinking of doing this as well. Did you replace the fuel injector O-rings and seals, or did you just put them back in? The Toyota repair manual says to replace the o-rings and seals for installation.

 

I've just replaced the plugs, and they looked like your pictures. The gaps on the old plugs are closer than 0.044", closer to 0.041".

I'm looking at removing the fuel injector rail, and I'd like to know how you did it. There's a hard line that runs back along side the block to a hold-down point held with a bolt. The bolt is behind structure, and though I can see it and can loosen it, I probably can't reinsert it if I remove it.

So, did you loosen that bolt to allow the hard line to slide forward a bit & thus let the unbolted fuel injector rail to move forward & disengage from the fuel injectors?

 

Kerosene? That would explain everything

 

I figured out how to remove the bolt restraining the fuel line today. With the wiper tray out of the way, I discovered I could reach the bolt with my left hand by reaching around the back of the block and along side the driver side of the block under the EGR assembly. I could use two fingers to turn the bolt once it was sufficiently loose. There is a narrow slot above the bolt in all the engine plumbing/wiring for an open-ended wrench to reach down to the bolt. A ratcheting wrench is really ideal - there isn't room for a socket wrench. Because of other obstructions, the wrench can only move about two "clicks" at a time, so getting the bolt out takes some time (it's about 1" long). The bolt is REALLY oversized for what it's doing.

The wiring harness that runs in front of the fuel injector rail is a pain to release. There is a bolt on the righ side but the left end runs down across the injector rail and is secured with a snap-in clip that is quite difficult to get free. Once that is done, and the two ground wires are detached from the block, the wire harness can be moved away enough to free the injector rail.

Once the fuel line restraining bolt is removed, there is enough flex and slack in the rest of the fuel lines to allow the fuel injection rail to move forward and disengage the injectors from the engine. The sides of the injectors were somewhat cruddy with some black goo, but the tips were clean. I cleaned all the injectors with carburetor cleaner, lubed the O-rings with dielectric grease and put them back in the fuel injection rail and in the engine.

After putting the wiper assembly back in the car, and hooking the 12 V battery back up, I started the car and the #1 (leftmost) fuel injector leaked gas from the rail. Damn. Took everything apart again & found the O-ring on that injector had become pinched somehow. I tried cleaning the injector rail hole, relubed the injector & put it back in. Same result when starting the engine. So I'm off to the dealership tomorrow for a couple of injector O-rings. Engine sounded fine while it ran, which is somewhat reassuring.

 

Today I replaced the O-ring on the leaky injector and no more fuel leaks from the injector rail. I'll drive it around tonight as a check.