MPG Decline Over Time

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jlglr4

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You’re fuel trims look pretty good, and if the pulse width is the same for all the injectors, I’d say you’re injectors are probably fine. Heard they’re a pain to get out.

Just eyeballing your chart, looks like there is a drop in the average mpg around June 2020. Maybe more local trips during the pandemic, or is that around the time you got the new tires?
 

ktm525

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I will come back to fuel. Was there an increase in ethanol in the 91 at that time? (ex. state mandated) Some premium fuels up here have changed from pure gasoline to 5-15% ethanol. Kills mileage.
 

cperez

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Start easy. Can of BG44K. Then plugs. BG sells an intake tract leaning service as well which may get some of the junk off the backside of your intake valves.

Then the expensive stuff.

Side question about BFG44K— is it best to put it in close to (before) an oil change vs right after a change?
 

f1racer328

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Alright, well this is embarrassing...

IMG_1983.JPEG


IMG_1981.JPEG


Both filters looked like this. Full of sand. New ones will be here tomorrow. Both air boxes were also full of sand, so I vacuumed and rinsed them out. MAF sensors look clean and dry. I do tend to off road a bit, and it's dry and sandy here...

I had previously checked them about a year or year and a half ago, but definitely screwed the pooch on this one.

Good news is the intake (post filter) is sparkling clean, so they're still doing their job... just a bit past retirement.

This probably has a small impact on performance.

Bonus footage of me shaking out one of the filters https://media.giphy.com/media/njYd5J0PIMnaOWW1Jz/giphy.gif
 

jlglr4

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It would be great if you would post back with your MPG after a few weeks. Would be really interesting to see what effect this has on the MPG.
 

f1racer328

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So I ordered new filters and cleaned the old ones until the new ones arrive (tomorrow)

I'm going to do a semi controlled MPG test today, and then run sea foam through my engine (motor treatment via fuel tank) and then maybe do the sea foam top engine cleaner (spray via intake)

I will keep the thread up to date if anything changes. Not going to remove injectors or plugs yet.
 

ktm525

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The good news is that an old clogged filter still filters fine, it just doesn't flow lol. I doubt you will see much gain considering the 5.0 has two filters. It would take a lot for the filters to be the restriction. That is a lot of sand though..
 

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