Increasing Fuel Mileage...

[Corey Bechtold]

Airjer or any other Mechanical wizards,

I recently bought a 1998 Chev 1500 with the Vortec motor. I have been trying to get it in tip top condition. First I replaced the brake pads and one rotor. Next I scanned the "Service Enging Soon" light and the code lists the EGR valve as a possible culprit. I don't know what that means but I'm sure it's nothing major (according to the dealer the compuer can reset the perameters to turn off the light). The truck has had a lot of warranty work from the original owner and it's in great shape.

That being said I have ran 3 tanks of gas through the truck and the fuel economy has been right around 15mpg. That is a mix of highway and stop and go driving. Is there anything I can do to improve the gas mileage? Also, should I worry about the "S.E.S" light? Lastly, are there any maintanence issues I should look out for with that engine?

Thanks,

Corey Bechtold

[UMDSportsman]

My comment before about the fuel filter, i don't really know if it will help gas milage, but the ten or twenty bucks you spend on a fuel filter every year will definetly pay off in the money you would spend having to replace the fuel pump.

[Scott K]

corey,

p0404 is usually from egr pintle sticking, or someone has had it off and put it on backwards, pintle for the egr should go towards the intake. remove egr ck if its on right and make sure it moves freely without sticking.

[Bassboy1645]

I cut of my catalitic converter mainly for the nice sound but I noticed an increase in mileage when I did this I was always told that old trucks back in the day had good mpg because they had no emission control dump in them.

[Macgyver55]

Quote:

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I cut of my catalitic converter mainly for the nice sound

but I noticed an increase in mileage when I did this

I was always told that old trucks back in the day had good mpg because they had no emission control

dump

in them.

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I sure hope you kept it! Its against federal law to remove or alter your emissions components or to even install an unapproved replacement converter. I believe it is also illegal to sell a vehicle that has had the converter removed.

[theoilman]

In almost all applications just changing from the OEM air filter to a K&N (or any other brand of oil wetted gauze) that mounts in the standard air box will not improve fuel economy. Some who say they get an increase are comparing it to a very dirty paper filter - not a fair comparison; compare it to a clean paper filter!

How do the oil wetted gauze filters improve flow efficiency? They Don't Remove Small Particle Dirt! People report long term higher maintenance cost on the engine - because these air filters let in all the small particle dirt! You literally are sandpapering the whole inside of your engine when you install one of these filters.

Only a vehicle that has a grossly undersized air filter for the amount of air flow required will get much increase. (Ford 1999-2003 7.3 diesels for example have one of the worst undersized air filters anyone has ever built in a vehicle)

If you change the complete intake system to increase sizes and it is properly 'tuned' can you get an substantial increase in fuel economy, but the real catch - None of this increase comes from the air filter, it all comes from the much better designed intake. And if you use an oil-wetted gauze filter you are back to the high wear sandpapering again!

In addition, car and truck manufacturers are now (for the last several years) starting to deny ALL engine warranties if it comes in with an oil-wetted gauze filter installed. The oil from the filter gives some emissions sensors troubles, plus the high wear situation caused by not removing enough dirt from the incoming air.

Another problem: cleaning them. Most people do not clean them properly, most people do not clean them often enough, and most people do not reoil them with enough oil (with no oil or too little oil you let even more dirt through).

Solution: Use a dry, high-flow, high-efficiency air filter! Small particle efficiency 50 times better, clean it with a shop vacuum - 5 minutes and you are on the road again.

[DinkADunk]

Quote:

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In addition, car and truck manufacturers are now (for the last several years) starting to deny ALL engine warranties if it comes in with an oil-wetted gauze filter installed.

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Are you sure about that statement? Do you care to site GM, Ford, or Dodge service letters that state that engine warantees are voided by the use of these filters?

[Valv]

I don't understand what's the problem stating a product is not as valid as claimed. K&N has been "the best" filter for many years, until recent studies proved the opposite.

Yes many mfg won't even work on your vehicle if they see it installed, and definitely won't honor any warranty.

I run several diesel trucks and I don't even come close to the K&N, there's a lot better filters out there and they don't cost as much.

[Whoaru99]

Manufacturers can't flatly refuse service or warranty repair for using aftermarket parts/fluids/filters unless they prove the damage or incorrect operation is the direct result of using said products.

IMO, this falls into the "Tie-In Sales" provisions of the Magnuson-Moss Warranty Act.

How far one takes it just depends on how hard you want to push the buttons and how many bridges you choose to burn pursuing it...

[Sonicrunch]

^^^As of late, I have been hearing of problems with the MAF and oiled filters. It seems the oil gets on the MAF's heated sensor wire causing erronoeus readings and premature failure. I can neither prove nor disprove this, it is only what I have heard via the grapevine.

Regarding fuel mileage, everybody has given good advice. I would like to add synthetic oil to the list. At the least, synthetic in you differentials. People may argue over synthetic in the engine and tranny, but I don't think anyone will argue against synthetic in the differentials.

[Jeremy airjer W]

Corey, I read up on that code last night. Basically the computer comes up with a desired EGR position based on the readings from the MAF and TPS. The computer then commands the EGR to match this position. It can monitor the posistion of the pintle and it needs to be withtin a certain percentage of the desired EGR position. I would imagine that you guys have a Snap-On scanner or equivalent? If you do then there is a test under the special tests function to check EGR. You can use the scan tool to open and close it while watching the actual posistion and the desired position. You will hear the engine start to struggle to run or even stall while you open the EGR. This is good! Even though the numbers may not match we know that it is functioning. As far as driving around with the check engine light on I personnally would not long term. If anything else fails you'll never know it. Little problems can turn into bigger problems if left unchecked!!

[Bassboy1645]

I sure hope you kept it! Its against federal law to remove or alter your emissions components or to even install an unapproved replacement converter. I believe it is also illegal to sell a vehicle that has had the converter removed.

Mcguyver55...I know...It still has a cat on it....it had 2 but ones gone...Everyone in town does that and the cops dont care as long as they dont catch you and your buddies reving engines in the neighbor hood at night same thing as straight piping in my book only I was cheap enough to not buy the pipes

[ScoutII]

Human nature is to use gadgets to make something better. A little improvement when I use this or that, but the real way to get better gas mileage is to drive responsibly. Avoid JACKRABBIT starts, slow down before a turn(brakes are not the only way to slow down, just take your foot off the gas pedal will slow you down), drive the speed limit or a little less, all things you can do and they don't even cost you money. I know it is a gadget world out there, but sometimes a simple less reactive way can get the job done better. Also it is a good idea to have your vehicle in good repair and operating at manufacurers recomended specs. Some fine tuning doesn't hurt, but it still takes energy to move an object.