Doing This Will Make Your Car Get Better Gas Mileage

Rev

your

engines, today I'm going to help answer a very common question, Scotty, suddenly my car is getting worse, gas

mileage

, what could be happening? The first thing I should check, of course, is the air filter, I don't know how. Many clients that I have visited, their car was slow and consumed bad fuel, the first thing I did was take out the air filter box and I discovered that it was all clogged with dirt, I checked it from time to time, I know that people don't do it . Look at things a lot these days, but check

your

air filter, they get clogged, you'll get horrible gas

mileage

, and don't fall for any of those silly claims some companies had that said, Oh, our air filter

will

help you.

better

gas, it's a bunch of nonsense, the filter that comes with the car was designed for the car and a lot of times if you don't get that OEM filter but you get a cheaper aftermarket one, it's worse for the car because they don't have as much filtration area and then clog faster, so you

will

get the worst gas mileage.

Now the next thing about the worst gas mileage is that you want to keep the oil clean and you want the right weight, whatever your car requires the use of the oil cap because of course the lighter the viscosity, the lower it is. the friction, the

better

the gas mileage, I've seen people put in heavier oil than the car was designed for, sometimes these things get 8% to 10% worse gas mileage, especially in a modern vehicle that could use 0w 20 oil, that is a really light oil, it requires using that oil, use the correct oil, you will find that they changed the oil and your gas consumption went down, you probably put the wrong oil in, now Another common thing that causes bad gas mileage is a dirty or faulty mass air flow sensor,

this

is the mass air flow sensor from a GM, if you look inside you can see there are little wires, those things can get dirty and then they give a false reading, I have a whole video on how to use mass air flow sensors to clean cars, it's called making your car run better with a little spray cleaner and you can do it from time to time. at a time to prevent dirt from building up in them, because if these mass air flow sensors send bad data to the computer you can get really bad gas mileage, anyone who knows how to use a scan tool can connect the tool scanning. and you can read the mass airflow data, if you're really into cars you can even get a thirty to forty dollar scan tool that will read the airflow and you might want to put it in your car when it's running normally. write down the data of what it's like when warming up and idling on the disk and see what the data is, your gas mileage will start to get worse, just plug in your scan tool, see what the mass airflow data is and , if it is very wrong you can try to clean it, if that doesn't fix it you can just replace them, they just bolt on and come apart, they are very easy to change on most cars, another reason why you can get bad performance from gasoline, especially in a late model car, you could just have a weak battery, absolutely everything works by computer in modern cars, if the battery does not have enough voltage the systems can fail, now it may seem crazy, but I have even had clients, One had a Mercedes that the engine cranked fine, but wouldn't start, and I have to admit I spent a reasonable amount of time checking all sorts of things to see why the vehicle wouldn't start, but I figured it out when I put my battery tester in the battery and showed that it was no good and needed to be replaced, even though it was starting the engine pretty fast, that would never have happened when I was a young mechanic, if the battery died it was good enough to start an old carburetor car, but these modern fuel injection computers

make

things work, hey, I had enough voltage to turn the engine, but there wasn't enough to turn on the fuel injection system and the electronic ignition system, as soon as put a new battery in the starter it worked like a champ so as crazy as it sounds check your car battery if it's getting worse gas mileage and while you're at it these machines also check the alternators and the The alternator and batteries work together so you just want to test both, it all takes like four minutes with one of these machines.

Now, the next common reason I see cars get worse gas mileage has nothing to do with the engine itself. , it has to do with the transmission, the transmission does exactly what it says, it transmits the engine's power to the wheels to

make

them spin, if it doesn't shift through all the gears smoothly you will get the worst gas mileage, and if it slipped , you will get the worst gas mileage, the transmission has a lot to do with gas mileage and with the modern computerized automatic transmission it is often a good idea to pay a mechanic like me to perform a transmission scan with our sophisticated scanning. tools, I've seen cars like

this

Mercedes behind me that show up four or five different transmission codes when you plug it in, and then I explain to the customer, that's why you're getting bad gas mileage, your transmission isn't working right, now The next big reason you can get bad gas mileage is because the problem in your brake system, the brakes are supposed to do nothing while you are driving down the road, then when you step on them they are supposed to squeeze the brakes. rotors. or the drums to make all the energy in the car turn into heat and stop the car, which is great when they work, but they get old a lot of times the brakes stick, all you have to do is lift the car. in the air they make the four wheels spin, if you see some they drag or you can barely turn them, your brakes are drag and it would be like driving with one foot on the brake and the other on the accelerator, now Years ago I had a client who was getting bad gas mileage on a BMW, I checked all kinds of things and couldn't really find anything wrong with the car, so I said, okay, we're going on a road trip you drive, so he driving his BMW and I looked at him, and he had one foot on the accelerator and one foot on the brake, and I told him why do you have your foot on the brake, he said well, that's how they taught us, one foot on the accelerator. one foot on the brake, so I made up some flimsy excuse and said well, yeah, let me go after you and I'll follow you and see if your car looks funny, well, the only thing I was looking for was to see if your headlights brake lights were on and the whole time I was driving down the road I had my brake lights on, which means I was driving down the road with one foot on the brake and the other on the accelerator, and of course, I was accelerating badly. mileage there was absolutely nothing wrong with the car, I couldn't find anything wrong with it, it was because I had one foot on the brake and the other on the accelerator, and stepping on the brakes will do the same thing, of course, now the last common thing To get bad gas mileage is to use the wrong fuel in your car, most modern cars are made to run on regular gas and they run fine, but let's say you have a car that needs super octane gas, if you put gas in it normal at least in modern ones, it will work fine but it will worsen gasoline consumption, it will not be as efficient, and vice versa, as crazy as it may seem, if you put high octane gasoline in it.

In a car that is made for normal gasoline, you can actually get worse gas mileage, the thing about high octane gasoline is that it burns slower and can also take more pressure before exploding, a high compression engine has to have a fuel that doesn't ignite too soon, while a low compression engine doesn't have to worry about that, you put high octane gas into a low octane engine, it won't destroy anything, it won't ruin it any better, but in fact you might make the gas mileage worse by

doing

that. . Hey, engineers design these things to work as best as possible on whatever fuel they're supposed to run on, don't mess with how they designed them, they know what they are.

Speaking of which, they have to work hard to try to get these cars the best gas mileage possible, and if you go against the way they designed it, that's a reckless move, now I bet someone will say Oh, Scotty no. You know what you're talking about, I have a very old car, it was made for regular gas and I put high test gas in it, and it actually improves the gas a lot, yes that can happen, but here's why it can This can happen because your old engine hasn't been taken care of and carbon is building up inside it, and as carbon builds up, carbon takes up space, so if it takes up space inside the engine, that increases the compression ratio. and it makes your engine a higher compression engine now, the more carbon in there, the less space, so when the piston compresses it, the pressure is higher, so you're actually driving a higher compression engine, in which case, older testing the gasoline will make it run better, but if you take apart an engine that old and want to do a physics test, clean all the carbon out of it, whistle it clean, and put it back together, you'll find that you'll get the same gas mileage it always had with regular gas, and if you test it high it won't make it run any better, that's a bit of a strange consequence of a high carbon engine, things aren't as simple as people usually I think they might be, you have to understand the big picture if you're going to talk about an old engine, all the things that can happen inside it, but for a normal modern car that you've taken care of, it says use regular gas. use regular gas you will get the best gas mileage with it so now you know the reasons why your car may have worse gas mileage and what you can do about it so if you don't want to miss another of my new car videos repair, remember to ring the doorbell!