Wow I had no clue this was possible.

[JHarris1385]

Pep do you think you have excessive exhaust?

[Pepino]

maybe im not sure, how do i know whats normal and whats excessive?

[JHarris1385]

Just wondering if you are running rich, I was and had to replace my fuel pressure regulator. Do a serach and see if you can open it up and check the condition.

[VehiGAZ]

Pepino, something is waaaay wrong - your mileage should not be that bad no matter how fast you drive. I drive ~90 mph on the highway to VT and I get at least 13 mpg.

If you have an oiled air filter (like a K&N) then you should clean replace your Mass Air Flow sensor (MAF or MAS). It measures the air coming into the engine, which the ECU uses to decide how much gas to squirt into the cylinders. The FPR regulates the pressure of the fuel in the lines, which also affects how much gas goes in. If either one of those is off, so will your fuel mixture.

You can get a new or rebuilt MAF at AutoZone, or you can use CRC MAF cleaner.

[Pepino]

i thought i got average miles per tank (260) but if you think that i am that bad then i must be really bad lol
i have the normal filter the one that come stock of course i check it all the time and its perfectly clean, one time i got only 153 miles per tank thats like ifi was driving a ferrari!! but then i changed fuel filter and it went up to 260 and its been around there all the time!
what can i do! where can i find a fuel pressure regulator? how much are they? i know nothing about car mechanics i am 19 and have no idea about anything of this stuff, back in mexico i never had to change oil or fix anything as soon as there was something wrong my dad sent the cars to get fixed so your help is appreciated

[VehiGAZ]

Sorry to alarm you Pepino - I thought you were getting 150 miles per tank regularly. 260 miles per tank is about right if you drive hard on oxygenated (10% ethanol) gas like I do.

If you don't know your way around an engine, then changing the FPR is no place to start learning. Any mechanic should be able to take care of it for you - an hour's labor to install it plus the part, which you could get at an Isuzu dealer, online, or from an AutoZone or other parts store. It may help, it may not.

[JHarris1385]

Do a search on here about the fuel pressure regulator.

I disagree - It is a very SIMPLE instal. The hardest part of the install is getting an allen wrench to turn the rear bolt (honestly).

It is about $70 bucks and if you can get the allen bolt off it takes no more than 20 minutes. I did this install and I am no mechanic.

I jumped from about 10 mpg to about 14-15 with just that. I am now running 17.5 average - and dont forget I am lifted with bigger tires.