V6 MPG

[12blkgrayRS]

My 2012 is stock with a manual gets about 20-23 in the city. 29-31 on the hwy. !8 is really low for this eng, leaky or dirty injector?? clogged air filter? Is it running rough at stoplights?

[AlanRubin]

Originally Posted by KillerBomb24

Its the high pressure pump. I can try to replace it shouldn't be to hard.

You need a TOOL to measure where the cam lobe is for the pump. You
need to turn the motor till the tool sits flush with the opening, then you
can put the HPFP in. You have to replace the OUTPUT lines to the
rails, they are one-time use. Not sure if they will seal again.


While this is all apart? Check the valve cover gaskets and plug valley
seals. You can do the plugs with the intake manifold on, so that's
not an issue. Check your intake manifold gasket. Remove the foam
insulation from the injector valley, and look in there for leaks. You can
keep the insulator off, you will just be able to hear your injectors...
Mine is off, so there is air-flow under the intake manifold. All that
foam insulation can come off, it's just for noise from the pump and
injectors.

Running without the engine cover, will also drastically lower air intake
temperatures, and overall engine bay heat. I can run 100+ miles,
stop for gas, the the intake manifold is barely warm to the touch, and
it is COLD in the winter when I stop.

If you don't mind the injector noise, then keep all that foam crap off
the engine. IF the radio is on, you won't hear any of it anyway.

[67-LS1]

You guys are gonna hate me....I have a 2013 LFX/6speed auto in my 1966 Chevelle. As my daily driver I’m averaging just under 30 mpg. I did one max mpg run; driving like there was an egg under my foot, coasting for long periods, never going over 60 and averaged just under 40 mpg on a 130 mile round trip.
I’ve got 3.07 rearend and 26.5” tall tires and it weighs 3,260 lbs with the tank full.

[KillerBomb24]

Originally Posted by AlanRubin

You need a TOOL to measure where the cam lobe is for the pump. You
need to turn the motor till the tool sits flush with the opening, then you
can put the HPFP in. You have to replace the OUTPUT lines to the
rails, they are one-time use. Not sure if they will seal again.


While this is all apart? Check the valve cover gaskets and plug valley
seals. You can do the plugs with the intake manifold on, so that's
not an issue. Check your intake manifold gasket. Remove the foam
insulation from the injector valley, and look in there for leaks. You can
keep the insulator off, you will just be able to hear your injectors...
Mine is off, so there is air-flow under the intake manifold. All that
foam insulation can come off, it's just for noise from the pump and
injectors.

Running without the engine cover, will also drastically lower air intake
temperatures, and overall engine bay heat. I can run 100+ miles,
stop for gas, the the intake manifold is barely warm to the touch, and
it is COLD in the winter when I stop.

If you don't mind the injector noise, then keep all that foam crap off
the engine. IF the radio is on, you won't hear any of it anyway.

Alright this sounds far to complicated for my inexperienced self. Sounds like $500+ at least if I take it to chevy. I may just leave it the way it is, its been like that for over a year. Ive gotten used to the check engine light anyway.

[ChibiBlackSheep]

Originally Posted by KillerBomb24

Alright this sounds far to complicated for my inexperienced self. Sounds like $500+ at least if I take it to chevy. I may just leave it the way it is, its been like that for over a year. Ive gotten used to the check engine light anyway.

Don't leave it. You are going to make things worse. One you are spending more on gas, 2 you are probably flooding the plugs, 3 you risk ruining the catalytics on the car and they are going to be even more money. Mine started doing this and then started to just stay running after i shut it off because of all of the excess fuel in the engine. Damn thing was acting like a diesel.


You don't HAVE to take it to Chevy, you can take it to a local shop. It's whatever you feel comfortable doing.


And it's going to be roughly $1200-1400 from Chevy. I've been there and done that.

[AlanRubin]

Originally Posted by KillerBomb24

Alright this sounds far to complicated for my inexperienced self. Sounds like $500+ at least if I take it to chevy. I may just leave it the way it is, its been like that for over a year. Ive gotten used to the check engine light anyway.

Replacement Video:

https://youtu.be/TqbfA9eD9zE


This guy does it without the tool.


The reason you don't just put it back on with the plunger out, is so you
don't strip the bolts putting the pump back on because of the spring
tension on it as you're tightening. He pushes the plunger in by hand, to
see how far back it goes into the bore. His looks like it happens to be in
far enough to put the pump on as is.

If you can push the plunger back at least 1.5" inches, you should be
good to put the pump on.

[KillerBomb24]

Just got back some codes. P0171 P0174 (lean bank 1/2) P0325 (knock sensor). Im guessing running lean for so long caused the knock sensor. I actually found a hole in the side of my cold air intake and that could be why im running lean. Either way my engine is not having a good time.

[KillerBomb24]

Originally Posted by KillerBomb24

Just got back some codes. P0171 P0174 (lean bank 1/2) P0325 (knock sensor). Im guessing running lean for so long caused the knock sensor. I actually found a hole in the side of my cold air intake and that could be why im running lean. Either way my engine is not having a good time.

The knock is coming from the canister purge valve solenoid. I unplugged it with the engine running and the knock completely went away. I didn't know knock sensors would trigger from this but when its unplugged the engine sounds fine. When these go bad, MPG goes down fast.
Im not sure if its the cause of my car running lean but its something not to hard to fix. This plus new spark plugs may fix my issues completely if thats the source of my problems. I also patched the hole on the side of my intake so thats one less leak.

[AlanRubin]

The purge solenoid makes a continual knocking sound when it's active. From what I
know, of other cars, they're not supposed to do that. They're controlled by PWM, so
I am going to try a 470uF cap across the terminals to knock the saw-tooth wave
down to see if it holds open instead of opening and closing continually. It never
interferes with the knock sensor. When I replaced it, initially, it didn't make any
noise. Seems to be a Chevy thing, because a guy I work with, his started doing it
and asked me what it was. I pulled the plug to show him, so his wasn't doing it
either, till it was, on a 2015 Fusion.

When they go bad, you will get a code for no flow. MPG goes down because the
engine is no longer burning those fumes, which are combustible. Disabling it will
also cause flow codes, and pressure in the tank, and MPG drop. Once the pressure
is high enough, you will get a code for that. You need the purge solenoid. IF you
vent it, you get a hi-flow code. Mine was unplugged from the line when I got the
car, so I had a hi-flow code, and fuel smell. Then the pump started leaking...

[12blkgrayRS]

Originally Posted by 67-LS1

You guys are gonna hate me....I have a 2013 LFX/6speed auto in my 1966 Chevelle. As my daily driver I’m averaging just under 30 mpg. I did one max mpg run; driving like there was an egg under my foot, coasting for long periods, never going over 60 and averaged just under 40 mpg on a 130 mile round trip.
I’ve got 3.07 rearend and 26.5” tall tires and it weighs 3,260 lbs with the tank full.

Now theres something you dont see everyday...i read your build chronicles....freakin genius!!

[ElderJ]

I just completed a 190-mile trip which was mainly on the highway. I recorded 26.4 mpg, which was a pleasant surprise.