Sh*tty MPG. HELP.

[blairracd]

My miles are mainly city miles, as I have a lot of school and work, but this tank I have gotten horrible mileage. I usually get around 220/tank.
Right now I'm looking at 100 for this tank.
Yes it's winter, I've warmed up my 4runner before going out, but no way should this have dropped so much.

Air filter, MAF/o2 sensor, fuel filter, cat. converter??

 

[jfeltT4R]

Dirty injectors? Dump some fuel injector cleaner in there and see if it helps.

 

[blairracd]

Dirty injectors? Dump some fuel injector cleaner in there and see if it helps.

Everyone recommends seafoam for this, and my dad for some reason is against buying it, but we have some B12 Chemtool fuel treatmeant stuff I've used before and I haven't noticed a difference but I will try again.

 

[jfeltT4R]

seafoam is good for injectors and overall cleaning. I keep a can in my garage especially for cleaning carbs. Another to try is lucas fuel injector cleaner. I saw the most results using the lucas when my mpg's dropped.

 

[gamefreakgc]

Everyone recommends seafoam for this, and my dad for some reason is against buying it, but we have some B12 Chemtool fuel treatmeant stuff I've used before and I haven't noticed a difference but I will try again.

Seafoam is great, you can use it in your gas tank, crank case and even through your air intake if you're careful and use it as directed. There's a reason why it has been around for decades: it works.

I'd also clean your MAF. Search for it on the forums, there's some real good picture writeups on how to do it without breaking it (the wires are VERY fragile).

 

[SURF RUNNER]

To Improve Gas Mileage

Seafoam - Anywhere for between $7.00 and $10.00
OEM Oil Toyota Filter (90915-YZZD3) Toyota $4.33
Mobil 1 Synthetic High Mileage 5W-30 Oil (5 quart container + 1 quart) Walmart $34.66
OEM Spark Plugs (Denso K16TR11) Rock Auto $24.64 for 2 boxes of 4
Same as Denso Spark Plug Wire Set/Blue (NGK 4412) Advance Auto Parts $35.99
OEM Toyota PCV Valve (12204-62010) Toyota $8.46
OEM Toyota PCV Grommet (90480-18001) Toyota $4.18
OEM Toyota Fuel Filter (23300-62030) Toyota $33.34
OEM Toyota Front/Upstream Air/Fuel Sensor (Denso 234-9002 - 2001-02) Rock Auto $108.99 each
OEM Toyota Rear/Downstream Oxygen Sensor (Denso 234-4261 - 2001-02) Rock Auto $47.99 each
Injen Air Intake (PF2055P - For 1999-2002 4Runners) CarID $225.00

I did a lot of research on air intakes... if you want some more info please check out the last few posts on my build thread.

 

[JayRolla]

Seafoam

I did a lot of research on air intakes... if you want some more info please check out the last few posts on my build thread.

Did you read how they suck in water?

 

[SURF RUNNER]

[MENTION=50342]JayRolla[/MENTION]

Mine is going to be enclosed (water proof and air tight) from the Safari Snorkel scoop near my roof to the engine intake. I am getting a custom cover made for the Injen air take.

I had a 2001 Corvette with a Vararam cold air intake. This utilized the Z06 vents on the lower bumper and sucked in massive amounts of air starting at about 8 inches above the road surface. My C5 was my daily driver and I never had one problem with water getting into my air intake.

 

[JayRolla]

[MENTION=50342]JayRolla[/MENTION]

Mine is going to be enclosed (water proof and air tight) from the Safari Snorkel scoop near my roof to the engine intake. I am getting a custom cover made for the Injen air take.

I had a 2001 Corvette with a Vararam cold air intake. This utilized the Z06 vents on the lower bumper and sucked in massive amounts of air starting at about 8 inches above the road surface. My C5 was my daily driver and I never had one problem with water getting into my air intake.

Nice, I just used turbos to suck in more air, intakes not so much. LOL. Again your setup looks like it will suck in more water from the front like that. Stock pulls from top of fender.

 

[jeff88]

There could be any number of things affecting MPG
I would start with the easy/cheap things first. Clean the MAF, replace the air filter if it's dirty, change the spark plugs. You might consider cleaning your fuel injectors regardless, just so you get better performance. If that doesn't fix it move on to the wires, the fuel filter, then the O2 sensor. I doubt it's your cat, you would more than likely get a CEL.

I'm not sure how a CAI is going to help your FE, especially in the city. More air means more fuel.

Also, idling your engine until it warms up isn't going to help you. You're getting 0 MPG for that whole time. Turn it on and go. (Unless you're talking about using a block heater, then disregard this.)

 

[Blitzkrieg]

I'm lost. Are you saying here your mileage suddenly dropped to like 7 MPG?

 

[foxrider56]

So is the 100 miles per tank estimated or actually calculated?
The gas gauge can just be acting up. Mine shows 1/4 when I actually have 15 gallons so I use a ultraguage to monitor it.
If that 100 miles per tank is actually calculated and not just a guess disregard what I said

 

[RedSled]

My miles are mainly city miles, as I have a lot of school and work, but this tank I have gotten horrible mileage. I usually get around 220/tank.
Right now I'm looking at 100 for this tank.
Yes it's winter, I've warmed up my 4runner before going out, but no way should this have dropped so much.

Air filter, MAF/o2 sensor, fuel filter, cat. converter??

So if i am reading this correctly? You say this happened from your last tank to this tank? If so my guess would be you got some bad gas, or water mixture. Also make sure your tires are inflated correctly, you would be surprised how much difference that can make. Anywho, let us know what it was when you get it nailed down.

 

[lhsoulrebel]

No check engine light? If you do do, I bet it's p0420... Change you O2 sensors.

 

[blairracd]

I'm lost. Are you saying here your mileage suddenly dropped to like 7 MPG?

Yes..

from (estimated from tripmeter) 220/tank to 100.





THANK YOU VERY MUCH everyone else. I will not be able to get to these things right away due to work and school but I will try to let you all know.

Thank you very much.

 

[derpiful]

It's a stretch, but if these things don't work, check for a brake that might be stuck.

Happened to me last week, and it's pretty uncommon, but it's definitely still a possibility.