2012 Pro-4X Sudden 3MPG drop!?

[StriderEF]

Haha - I should have said that I read a lot of positive reviews of xterra fuel efficiency compared to the older ones. Seems like 20MPG is a reasonable expectation for interstate travel in a new pro4x (unmodded).

My issue with crap MPGs started a few months ago back in Delaware however, where it is possible that I got many tanks of crap gas. I'm planning to run a bottle of techron through each tank for the next couple tanks. I also bought a bottle of seafoam to run through the engine and the tank, but need to read up on how to properly do that first. I'm no mechanic so I'll take you up on that offer when I'm free of the office one day!

(Sidenote: noticing your avatar, I will add that while I'm no car mechanic, I am a gunsmith. I grew up in my father's gunshop in Fort Smith Arkansas, and plan to start shooting compettively again now that I'm back in nashville.)

[mac11]

dont waste your money on the techron or seafoam. Those are basically solvents for cleaning up dirty old crap.

my hunch is excessive water in the fuel system for which you need a demulsifier.

From wikipedia...


Demulsifiers, or emulsion breakers, are a class of specialty chemicals used to separate emulsions (e.g. water in oil).

I'm getting more familiar with them now that my other vehicle is a diesel but I just gave myself a good reason to find one that works in gasoline as i left the tank lid on my bike open last night during the rain storm. (shit!) Give me a few minutes and I'll look up what should work for us.

[mac11]

for gasoline basically you need a good amount of methanol to act as a demulsifier.

[StriderEF]

2/25/2013 UPDATE: ECU reset FTW! Yesterday was sunny and beautiful so I took the Truck Named Sue out for an ECU reset. Unhooked the negative cable for 40 min while enjoying an excellent cigar with a buddy, then we reconnected and took it for a 60MPH drive south down I65 out of Nashville. Never broke 2000RPM and drove out 30 miles then right back doing same. All in all, I drove it 60 miles doing 60MPH and the truck computer was estimating my mileage at 22.2 MPG!

I know these things are often way off and will measure the next few tanks manually as normal, but man oh man, that was a number I've NEVER seen on the Xterra. EVen if the real mileage is ANYWHERE close to that, I'll be one happy freakin camper!

Will keep you posted over the next couple tanks to see what it does with in otwn mileage and driving at 70 MPH. If this holds through March, I'll order my Shrocks at the end of the month!

Thanks all and stay tuned!

Son of a Gunsmith.

[Jackal]

2/25/2013 UPDATE: ECU reset FTW! Yesterday was sunny and beautiful so I took the Truck Named Sue out for an ECU reset. Unhooked the negative cable for 40 min while enjoying an excellent cigar with a buddy, then we reconnected and took it for a 60MPH drive south down I65 out of Nashville. Never broke 2000RPM and drove out 30 miles then right back doing same. All in all, I drove it 60 miles doing 60MPH and the truck computer was estimating my mileage at 22.2 MPG!

I know these things are often way off and will measure the next few tanks manually as normal, but man oh man, that was a number I've NEVER seen on the Xterra. EVen if the real mileage is ANYWHERE close to that, I'll be one happy freakin camper!

Awesome news! Isn't it amazing that disconnecting power fixes so much in these computer equipped cars? sometimes I wonder if all of us should have an nationwide Xterra ECU reset day every year just in case. Maybe we could do it on earth day.

If this holds through March, I'll order my Shrocks at the end of the month!

Doh! MPG

[StriderEF]

Haha. Yeah that is just amazing. I'm not sure how/why it went off the mark like that as I never disconnected the battery for more than 5 seconds since I bought it. Regardless, I'll happily watch my MPGs stay up where I though they should be for months.

I'll be totally fine losing a couple back to Shrock front and rear bumpers though. I did all that math before I bought the truck in August. This whole thread was started because I had no idea where all my MPGs went suddenly and without reason. It was like I had already installed Shrocks and was carrying another full set in the trunk!

Figure once my mileage proves itself to be ballpark of 20 with only the KN drop in filter, I'll add the bumpers, lose a couple MPG, and hopefully add exhaust and gain back some power and maybe an MPG.

[Jackal]

Yeah the protection from shrocks in an impact will be worth the MPG drop from some of the pics I've seen. Its like insurance for your a$$.

[Revu]

Glad to hear that finally did the trick!

With everything you did to try and kick the MPGs back up it should definitely be in the high teens. Good luck keeping it up there and with all your future mods too

[StriderEF]

thanks much. I'm really hoping this MPG recovery sticks. Today and tomorrow I'll be commuting 60+ miles each day mostly on the interstate at 55-65 MPH, so I'm hoping to see some realistic improvement there. I don't think for a second I'll really get 22 on the interestate, given that it was a beautiful day and I just set the cruise control to 60. Regular driving should be less, and my big commute last night and this morning has evened out with some city driving to ballpark of 17.8 (according to truck trip computer).

I just put a fresh tank from Exxon into it Sunday night and seeing the DTE gauge read 386 Miles to Empty was frickin awesome! I'll report back with mileage at end of the tank later this week.

[StriderEF]

Oh yeah, a buddy of mine who races bikes professionally said the noise I thought was dripping from the undercarriage was just the various types of metals under there cooling off after a drive. The only drips (i.e., water) I've been able to find was coming from exhaust and maybe the compressor.