I performed the ISR mod on my 4runner about a year ago, ever since I have been getting an average of 11 MPG. Before the mod I was getting an average of 16 MPG. I've put in new NGK plugs, wires and cap; run several bottle of Seafoam throught the PCV and in the gas tank; changed the air filter; and triple checked all the hoses and connections related to the ISR. Any ideas?

 

It sounds so awesome when you floor it that you do that all the time without thinking about it?

Actually, in all seriousness, when I first did mine I noticed a drop in mileage. I keep my foot out of it now, and my mileage is about where it should be with 33's and 4:10's.

 

I'm thinking about doing the ISR and MPG is a big deciding factor in doing this.

Anyone else want to chime in on the ISR mod and getting bad gas mileage?

 

Explain to me what the isr mod is?

 

I.S.R.

Intake
Silencer
Removal

The search feature is your friend, do not fear it .

I put on a new intake and noticed a gas mileage decrease... because I can't stay out of the throttle now, lol. The quick hiss it makes when you open the throttle and the deep romping noise it makes when accelerating makes me feel like I'm in a Ferrari... until I realize I'm only doing 35mph at the end of 2nd gear...

 

lol i can never get that search thing to work for me lol
35 in second gear wow you made my truck seem like a ferrari lol

 

...I have small tires... but it get's to 35 in a hurry!

 

I know its bad but with 31's i can do 45 plus before she revs out. (only used when i cut some one off.)
p.s. im a trained perfesional dont try this at home lol

 

lol, around here, that's what we call a "Hey yall, watch this $#!@" quote. I try not to take her over 5 grand too much; the shift light's set at 4 and a quarter...

 

I really didn't notice any sort of drop in mileage.

It seems no matter what I do to my truck, I can never get more than 1-2 more mpg. Per tank I only get 200 miles. Always.

I have done the ISR mod, put new NGK Irridium plugs, took off my runningboards for the weight, along with removing some crap inside too. I also changed my fuel filter...

I tried running better gas.
I tried being a grandma driver (only increase about 15 miles per tank..)

Gas mileage is a Witch with a B. The truck is in charge in that department.

BTW I get about 12 straight. This is all city type driving with 31's...


Ps, What I have noticed about my ISR is that it takes a couple more chugs to get the engine started. I think its because my ISR tube is like 4'', and to create a vaccuum on that takes an extra breath.
Exibit A.

 

Very clean infiltrator, I've noticed the same after my intake install; it's take a little more turn-overs to start it every once in a while, even on the 22re.

 

With the size of your new intake piping it may be taking a few more milliseconds to get the MAF trapdoor to react.

A

 

Thanks, I take pride in cleaning my engine and my hoses with degreaser and then some tire cleaner.

Looks brand new when I am done.

 

...makes perfectly good sense... it's a new AFM too; well, used technically, but works, unlike my old one, lol.

 

i had my 86pu with a 20r doin 50-55ish in 2nd gear sorry for the hijack

 

Just trying to learn here sorry to hijack, but what makes a car with 6 gears better than a car with 4? I mean, sure it may be smoother, but still I don't know why...

I know dragsters only have 2 gears... I mean I guess you could say acceleration is better with more gears, but going back to the dragster, its fast as hell but only 2 gears.

 

I did the ISR Mod ,and after a week it went back to normal. Lost 50 Km(30 miles for you folks behind the times) I did nothing in the way of driving changes,so I have to give this a big 2 thumbs down.

 

I think its an attempt to keep the engine in its power band during driving.

 

I've done a lot of tuning on my '92 that has affected gas mileage, but the ISR mod had neither positive or negative. Then, it's not really the idea behind it....increasing mileage, that is. It's major purpose is increasing throttle response.

For those who've noticed a decrease, have you also notice whether or not your vehicle was/is running richer in fuel?

 

It may be purely coincidental as to the timing of the mod and decrease. I'm averaging 16mpg with hauling right now.

How is the vehicle running otherwise?