Alright guys so my 22re a few months back was averaging between 28-29 mpg hwy and its been slowly decreasing since. Now its at about 21 I've always kept it well maintained so idk why this is happening anybody have any thoughts or has something similar happened to you? Everything is running fine on my truck it just feels a little slowerand gets worse mpg. It has nfl iridium plugs msd wires Lce header intake. Any ideas would ne appreciated. I think its the oxygen sensor or an emissions part. But I don't feel like blindly throwing money at it
...help!

 

Most mechanics can test O2 sensor to see if they are good or bad. I would try running an injector cleaner like lucas or seafoam before to see if that shows a noticeable increase.

 

Well I just ordered an ntk o2 sensor because I figure with over 200,000 miles either way I should replace it. Also there's no point in using a fuel injector cleaner because 5 months ago I removed them and had them rebuilt cleaned and flow tested and since I've only used premium gas from chevron or shell :/

 

winter gas?

 

i do not understand a problem 12 litres per 100 kilometres is actually good, moreso if it is not done out on the open road.
in the 4x4 versions 16L/100km or 4 gallons to 60 miles when bigger wider tires, roll bars driving lights are fitted.
the 18R-C nor the 22R in any version were fuel misers, here in australia we had the 3Y and 4Y because after the 18R the 20R failed to meet our emission standards for commercial vehicles and only the 22R-E was in the last of the sixth generation hi lux before the 2RZ-FE and 3RZ-FE seventh generations.
petrol "gas" in australia is not cheap and the 3Y and 4Y had far better fuel economy, the few import cars that had the 20R and 22R were known as dogs with poor fuel economy and power so those in the know stayed well clear.
we here in comparison pay more per litre than you would per gallon, so we pay more than four times the price for fuel.

 

the mpg was also decreasing in the fall so i doubt it has something to do with weather.

Whysmee - for about 3 months straight i was consistently getting 29 mpg hwy. the 22re was not the most fuel efficient engine in its day but it doesnt change the fact i was getting 29mpg, im just trying to see if there are a few parts that that can be replaced to increase mpg, besides normal maintenance stuff

 

air density makes major differences between summer and winter, some of the earlier non fuel injected engines had a winter summer setting on the air cleaner. basic fuel injection systems use only an O2 sensor in the exhaust and as fuel injection systems get more technical some now have a sensor that uses the atmospheric temperature as well as throttle position, MAF or MAP sensors along side the O2 sensor. here in australia with the older non fuel injected engines different carburetors where fitted factory "jetting" according climate of where the car was sold as new, example to take a car from the cold south to the tropical north they would run poorly and the opposite, as the fuel to air ratios were different between tropical and alpine conditions and new fuel injection setups are getting more advanced to solve such issues.
i doubt you have anything wrong with your engine, i just think it is because it is colder and more fuel is needed much like having the choke pulled on slightly or using the winter setting on an older non fuel injected engine

 

Double check timing also. Little retarded will cause power loss and fuel economy drop. But im getting 22mpg and ive never heard of 29 from our little truck. But then again I have a heavy foot

 

I get 23-28 with driving @ higher speeds.
Got 32 on a 200 drive back from a show, staying @ 65 the whole way!
This is with a LC Pro Street 22re!

 

Last winter I was getting about 27mpg and besides the 22re does not have a system to measure intake temperature which means in cold weather it would run slightly lean and in hot weather it would run slightly rich.

Timing is 2 degrees advanced over stock setting.

I drive once a month from norcal to Socal about 400it miles the best mileage I have ever gotten was 29mpg at ~70mph. Recently it has gone down to 22mpg at ~70mph

 

The VAFM in our trucks have a temperature sensor (IAT).

My truck gets worse mpg's during winter... I think it's the cold air that's more dense, so the o2 sensor also adjusts to make it less lean.

Have you changed your intake filter?
I got 20-21mpg driving around (more city) and that was trying to conserve fuel.
I changed my air filter, drove like a jackass for a whole gas tank, and I got 20mpg. I over looked that air filter for about 2 years.. maybe 3... LOL. so it did make a difference on my part. I'll see what the mpg's for this tank will be, that is if I ever finish it.

When's the last oil change? What oil? Filter?

Where'd you order your o2 sensor? Hopefully RockAuto for $60

 

The intake filter is a K&N cone that was cleaned two months ago. Oil change is almost 4000 miles on royal purple oil and Mobil 1 filter. Even when I changed the oil last time mpg was unaffected, if so very little. O2 sensor was ordered from summit because I had a coupon and they sold oem ngk oxygen sensors.

I know for a fact I was getting 29about mpg hwy january through august last year. Just trying to figure out what other parts could drastically change mpg like this.

 

I just posted a reply on another person's thread, but i was wondering if you may possibly need to adjust valve lash by any chance.
I'm not sure what's going on either, man.

 

well i adjusted the valves about 7 months ago i guess i could do it again but i just hope the o2 sensor does the trick

 

Any update? I have ran into the same issue of drastic drop in MPG. I did a TuneUp (cap rotor wires plugs oil and filter and air filter) I was getting 26-28 on my long trips and last one down to Sacramento I got 22 there and back

 

Any update? I have ran into the same issue of drastic drop in MPG. I did a TuneUp (cap rotor wires plugs oil and filter and air filter) I was getting 26-28 on my long trips and last one down to Sacramento I got 22 there and back

 

Not really. I installed a new ntk oxygen sensor but if there was a change in mpg it was barely noticeable. I think im going to wait until summer time comes around and compare my mpgs then.

 

I dont know about left coast refineries,but here in the northeast they oxegenate the fuel in the winter to help with emissions. most people report losing a few mpgs. then in the spring it goes back to normal.

 

^^^ I don't remember that happening last winter but I hope that's the issue because with fuel climbing I'm going to have a hard time with my stereo trips. I put almost 20k on my pickup last year.

 

Ckeck where your egr goes to the back of the throttle body by the sensor if its cool and the rest of the engine is hot then the egr is clogged or is not working. There's other ways to check it but this is the easiest. I had the same problem on my 89 22r-e. I got a used egr at the junk yard for $60. I was down to 19mpg now I am back up to 28mpg. Hope this helps.