I have 2000 Blazer Trailblazer. I bough it a few weeks ago and I noticed I am only getting about 10 mpg. I replaced plugs (double platinum), wires, air filter (fram) and did an oil change. It only has 73000 and I can't figure out what is causing the low mpg. I don't have any misfires and it seems to run pretty well. What else could I do to better my mpg? If anyone could give some advice that would be great.

 

I would love to help you because I've been on this journey for a while now as well.

The first thing that comes to mind from your post: have you used seafoam yet? If the engine is running well, then I would just pour half a can into a full gas tank and save the other half for later. If you still have crap mileage and it's not showing signs of improvement, then pour the other half of the seafoam into the induction system. Go to youtube to learn how to do this. It's very easy. The reason I suggest seafoam is because it's <$10 and pretty easy to operate and can be the easiest fix in the case that you have gummed up injectors.

Spray MAF cleaner onto the MAF and let it dry thoroughly before reinstalling. Grab throttle body cleaner and clean off the blade and the hole in the middle. Then pop off the belt from the tensioner pulley while the car is cold (for convenience) and spin all of your pulleys to see if any need to be replaced. Spray the PCV valve with throttle body cleaner.

Check your differential fluid. If it's black and soupy or if you can't find any in there, then pop off the cover and install a new one then fill it up with good fluid. I put Royal Purple diff oil in mine and am very impressed. My MPG went up by 1 after the diff change.

Use synthetic oil, by the way. This is probably the easiest way to start getting better mileage. It's only got 73000 miles which is fair, but who knows what's lurking in the engine. Flush it out! I bought an engine flush from Napa that I was satisfied with. Cheaper than the BG engine flush we sell at the shop and very easy to use. Use the product then if you want to go nuts with it, run a quart of new oil through and drain that out (unnecessary). Fill it up with Royal Purple. It's worth it, my friend. After my first RP oil change on this engine I noticed a 1.5 MPG increase on the highway.

Align and balance. You/whoever might discover some suspension issues when they have the wheels off. If your wheels are pointing opposite directions on the alignment rack then that is a big explanation. The tires need to be balanced also. If you trust your shop (hopefully), you can ask them to look at the rotors and see if they need to be turned. Brakes are easy money for shops, so be careful.

If after all of this you still are having trouble with your fuel economy, I don't know what it would be unless you're riding on 35 inch tires.

 

I'm gonna say use the search function and look for fuel system diagnosis!!!! trust me with these trks u wanna check your fuel pressure....... U may just find the issue right there!!!!