you can also put it into your intake system. take the big vacuum hose off the master cylinder and let suck up about a cup. do it very slowly to prevent hydrolocking the motor. when its all gone, turn off the engine and it will clean out your system. let it clean for about 10 minutes and then crank it back up in a well ventelated area. it will probably smoke like crazy. i was pretty nervous the first time i used it, but it was all good.

it is an additive for your fuel, pour a full can into a full tank of gas and run it out over time.

it is not an additive for the oil, i recommend when you add it to the oil, you will need to change the oil in a hundred miles or so.

i saw a diffrence


do a search for it on youtube and you will see how to put it in the intake

+1 one to the vacuum intake method!

Lots of smoke came out, and soot was all around the tail pipe. Quite funny driving down the road smoking everywhere.

My idle is much better now, I have not seen a different in mileage, still around 17mpg.

try out the tornado air managment system (go to: www.summitracing.com) i have one on my XJ and i am alble to get 2 additional MPG. whoopie!!! i also changed my driving habit by driving like a senior citizen. haha

Napa sell some great injector cleaner called 40/40 to add to a full tank! Its a little pricey but works great!!!

I'm surprised us jeep folks really care that much about mpg since it's bascially a urban tank after you get a lift and tires haha. but agree with the others, CAI, injectors, seafoam, tire pressure always correct, oh yea new 02 sensors may help don't think that was mentioned, pedal technique etc...but in my humble opinion SUV does not like MPG hince cash for clunkers lol. I guess my 92' xj is a clunker oh well. good luck.

x2 on that.

but also in response to the o.p's question, i got a speeding ticket last week (90km/h in a 60km/h zone) and since then some magical spell has been placed on me where i wont drive more than 5 - 10 km/h over the limit! its so weird.. i'm 18 and i feel 80 lol. BUT... i've noticed a big big difference in my gas mileage. so a combination of injector cleaner, proper tune up (plugs, air filter, etc), seafoam and somewhat more civilized driving habits should do the trick.

Thanks for the great tips.

I drive my xj to the country most weekends and need to use 4x4 for the dirt road on the last mile. It's the other 118 where I want better mileage

After watching some of the Seafoam videos and reading some of the instructions, I'm a little freaked to try it out esp. pouring into the engine through the air intake.

Anyone have any other good/bad experiences using the foam?

Thanks for the Tornado tip, I've also read about replacement Air Filters that claim to improve mileage but they are more expensive. I'll post back with my experiences.

i dont know that the tornado really does anything. dont waste your money on a throttle body spacer either.

I seafoam before every oil change. It works great. it helps get rid of some of the carbon buildup in the engine. just take off your intake tube, and pour it slowly into the throttle body while the engine is running. you will have to rev the engine by hand to keep it running. now...i use about half a bottle this way. then ill pour in a good bit, where the engine starts really stuttering, and ill run over and shut it down. let it sit for 15 minutes...come back, start it up...and rev like there's no tomorrow. I get the most white smoke with this method, and every vehicle ive owned always seemed to run better after words.

once the white smoke is gone and the jeep has cooled down, then i change the oil and filter, because it will get gunk in your oil. Also, if this is the first time doing it, you may want to go ahead and change your spark plugs afterwords, because it might gunk them up as well.

You might try resetting your PCM and then apply some "milder" driving habits as others have suggested. The PCM will resample data from the sensors and adjust it's engine control profiles based on the new data.

I reset my PCM and drove at 60-65 highway and kept a light foot on the pedal around town. My mileage has gone from 17 to 21mpg in the space of a couple of weeks, approximately 500 miles...

BTW, the SeaFoam stuff is great too! Well worth the application.

Cheers.

I dont know if I would do the sea foam thing all the time, I have had some bad experience with useing something like sea foam through a vacuum line while running. Once a piece of carbon came loose in the combustion chamber and got lodged in between a piston ring and cylinder wall, it started knocking pretty good It eventully came loose and stopped knocking, but if it had not come loose we where looking at explaining to the customer of the car that the knocking started when we did the tune on it.
So now I use marval mystery oil in the gas tank and in the engine crankcase on a regular bases and it works great.
Useing it in the tank will loosen carbon in your combustion chamber slowly with out the harsh all at once method, it acts as what they use term as a top oil for the rings and valves, just dont use it just before you are going to get it smoged because it will show up as unburned hydrocarbons and may not pass.

My XJ is 2.5 4 cylinder 87 year and it did not qualify for the clunker thing because it was rated at 20 mpg.
I have gotten good mpg on it, and what eveyrone else is saying just keep a good tune up on it and proper tire pressure, "except when wheelin" and learn to drive like one kid said her drive like an old man, myself I am not old but I like my cheap insurance rates for good driver, and besides here in California speeding tickets are out the roof in cost now.

What kind of injectors should i get?

wait. 2.5. Speeding? That's possible? It's barely possible in my 4.0 lol

As for gas mileage improvements, the Chevy Volt can be leased $0 down first month paid $275 for an entry level trim...