Dodge Neon low mpg

[Gealii]

Originally Posted by Antigrav01

Gealii, do you mean just replacing the exhaust system? Because I was going to do that anyway for performance and aesthetic reasons. Not any time soon though.

it was the headers i had to cut beings i could not get anything up next to the bolts to loosen them. the rest of the exhaust was fine. replacing normal exhaust does not include headers so hope you never have to do this if you drive easy u shouldn't have to. The only reason mine quit was because everyday after school i would be doing about 130mph bumper to bumper with 2 other kids...never again and the oil pump quitting was actually what got me into ecomodding so i guess i should be thankful for it

[fltrplntman]

Originally Posted by Antigrav01

Im assuming no spots should be underneath a car whatsoever, no matter how small. If yes, then yeah I probably need something to do with my oil fixed. Sensor, pump, hose, whatever. Ill check into it soon. Engine temperature stays rather cool, so I doubt its the coolant. But yeah, 2000neon, I think I was turning right. It didnt immediately turn off, but it didnt last long.

None of my brakes drag (that I know off), but the rear ones arent tight at all. Basically if my front brakes ever malfunction while im driving, im screwed.

Actually now that I think about it, ive been having this sort of mpg every since I got the car and the oil level was perfect then. Gahh, friggen oil and timing belts. Id go electric if they could match the same range and power...and price. Im kind of eager to get everything checked over soon to see if simple maintenance was the problem. I suppose I could go ahead and do it early... And if it is a wearing out timing belt, thats something I need fixed immediately. What should I look for in terms of wear and tear in a timing belt that might not be obvious? I dont have any experience doing this .

Gealii, do you mean just replacing the exhaust system? Because I was going to do that anyway for performance and aesthetic reasons. Not any time soon though.

EDIT: I just went outside to check the oil level and its right on the max line, though I remember it being a little higher last time I checked before. Its also getting a tad brown. I also have an MSD ignition coil. I dont know when that was installed. I know I didnt do it. Not that I forgot to mention it before, I figure I might as well now since I was just under the hood.

Timing belts will show small cracks around the teeth of the belt. BUT.. Just have it changed. Its expensive, but at the same time, its cheap insurance. If the belt breaks, it smashes most of your valves. At least 4 of them. This repair is much more expensive.

Have an alignment done. Older cars tend to start sagging in the spring department. This tends to change camber and toe in/out, causing drag.

Have your oxygen sensors checked. If these start going bad, they tend to fail rich, = more fuel.. less mileage.

Make sure your thermostat is working properly. The new style T-stat fails open, causing the engine to run cool throwing off the fuel mixture.

Tune up.. plugs, wires, and air filter if you haven't already.

Use a quality fuel injector cleaner such as Techron. This will do wonders if the injectors are dirty.

Seafoam.. Only pour it in the tank and in the oil. NEVER suck it in the engine via a vacuum line. It could pool up and get sucked in the engine and hydralock it.

A thinner weight oil will help a little too.
Hope this helps.
Good luck!

[Antigrav01]

My dad knows a mechanic that will change my timing belt for $300. He's the one who replaced the speed sensor and solenoid. Ill check the condition of the belt when I get back to the parking garage my car is at (im sitting in class right now).

As for alignment, ill have that done when I get my new wheels on. Theyll need new tires, so once these wear out, ill buy and mount new tires on my new wheels and get an alignment the same day. And im going to get lowered and stiffer springs eventually (1.5" lowered at the most), so I think it would be a waste of money to replace my current ones and then replace them again with the lowered springs. There doesnt seem to be any sag right now anyway. They seem to be in good condition.

[2000neon]

When you say that engine temp stays cool, how do you know? If it is by the factory temp gauge, on my 2000 it only showed about 1/3 of the way up the gauge. There were two marks, one about 1/3, one about 2/3 of the sweep of the gauge. Mine always ran right at the lower 1/3 mark or just a hair above. I always thought it looked low (would assume it should be right in the middle) but I guess not.

[fltrplntman]

Originally Posted by 2000neon

When you say that engine temp stays cool, how do you know? If it is by the factory temp gauge, on my 2000 it only showed about 1/3 of the way up the gauge. There were two marks, one about 1/3, one about 2/3 of the sweep of the gauge. Mine always ran right at the lower 1/3 mark or just a hair above. I always thought it looked low (would assume it should be right in the middle) but I guess not.

Most cars have 2 temp sensors. 1 for the gauge, and the other for the Fuel Injection. They usually run between $7-$20 depending on the car. If its running low, you may think of a new thermostat also.
By the time everything is all said and done.. you'll have a pretty reliable little car. ;-)

[Milwaukee]

bad Thermostat can cause this terrible gas mileage.

Had couple fleets I notice summer it was great on gas but the colder outside it was WORSE and notice it get longer to warm up it turn out thermostat wasn't work correct it let engine running cold make computer think cold need injector more gas gas.

[Antigrav01]

Im not sure where the needle should be on the temperature gauge, but it looks low to me. Even after driving for half an hour at 55mph+ speeds, the needle is about at 1/4. Actually, heres a perfect picture I found of what it looks like. Mine is just a little bit higher than the one in this picture. http://www.thecarconnection.com/imag...rument-cluster
Does that still seem suspicious? Well, im glad the replacement parts are cheap.

How exactly would this effect gas mileage though? I mean, I completely understand things like faulty spark plugs or clogged intake filters causing a problem in efficiency, but a thermostat or temperature sensor?

[2000neon]

Hmm so it's a 1/4 way up on the gauge? Yeah that seems low to me too. I don't have the car anymore so I can't even go out and check, but I know that mine never made it up over 1/2, except when it overheated... Anyways, it always drove at just at or slightly above the mark at 1/3 rd of the way up the gauge (assuming your gauges are the same as mine, but I think they are). There is an old school way to check if the thermostat is working, stick it in a pot of water on the stove and crank the heat, you should see it open. And use a meat thermometer to check temp.

[Antigrav01]

You know the two thin lines between the bold ones? Mine never seems to go past the bottom thin one. Maybe thats more like 1/3 actually.

[2000neon]

As a reference: My gauges looked like this,
2002 Dodge Neon Gauges Photo #47448868 | GTcarlot.com

My temp gauge was always at the second line, the one a little below half. So anyways I guess my point is, even if it seems low on the gauge, it may not actually be, see if there is some way to verify the temp or where it should be.