very high Fuel Consumption

i have a 99 Saturn SL2, auto, with 112000miles. It used to do over 300miles off a full tank of gas. If i drove conservatively it used to do 350 miles per full tank of gas. But during the last year it does less than 200 miles with a full tank of gas. and i'm tired of going to the gas station every ~190 miles. Any idea what the problem is? any suggestions?
thanks

What does your temp gauge read normally? If the engine is running too cool, your wasting fuel. Also, if your coolant temp sensor is bad, that will also waste fuel. Do you have a check engine light on? Checked your air cleaner? Had a tuneup lately?

What does your temp gauge read normally? If the engine is running too cool, your wasting fuel. Also, if your coolant temp sensor is bad, that will also waste fuel. Do you have a check engine light on? Checked your air cleaner? Had a tuneup lately?

Thank you for the response, temp gauge is the same as the day I first bought it. NO lights on. air filter is new. I do regular tuneup. any other suggestions?

Ok, but what does the temp gauge read? Your ECTS could be shot telling the PCM that your car is not warmed up and dumping a rich fuel mixture. You could have a leaky fuel injector or a lazy O2 sensor.

Ok, but what does the temp gauge read? Your ECTS could be shot telling the PCM that your car is not warmed up and dumping a rich fuel mixture. You could have a leaky fuel injector or a lazy O2 sensor.

thank you for taking time to read and respond to my posts. the temp gauge is at 1/4th mark. It has always been at that mark from the day I bought it. What should I do? Should I be replacing the ECTS? or what can I do to make sure what the exact problem is?

Is your SES light on? Are you sure it's working? Does it come on when you first start the car?

Is your SES light on? Are you sure it's working? Does it come on when you first start the car?
There Are no lights on. Yes it comes on when I start the car.

That's a stumper. Everything I can think of that would cause this would trip a SES light and throw a code.

I removed the ECTS and found a small crack on the sensor. replaced it. and I hope this will fix the problem. I'll post an update.

My mpression is that the temp gauge should read just below half way up the scale. If it reads lower than that, its probably aged enough to be affecting things. We have a 98 and a 92 SL2 in the family, and both of them got replacment ECTS after we bought them (used), though the SES light wasnt telling us of any problem. Since then, both cars gauges read about mid scale on the temp scale in normal running, and give over 30 mpg on highway driving.

i had this same problem with the same car at 124,000. we finally settled on a fuel pump for a $108 and it did not help at all. i tryed treatments and my mechanic did everything he could think of. and then while fixing something else he pulled off the top of the throttle body housing and that dang thing was almost clogged shut with carbon build up. we cleaned it with god knows what probably brake fluid. lol. and it has not sucked gas like that in over a year now.

hi sorry new here where exactly is the ects thing at? I have a 96 sli with 152,xxx, and I am getting like 19 mpg when 6 months ago i was still getting 30, my temp guage is always at half or a little above, but I want to at least give this a try. thanks in advance

http://www.saturnfans.com/forums/showthread.php?t=37884

ECTS replacement completed with a 13 mm deep six point socket on a cold engine.

didnt realize this was the name of the sensor. I changed this one day in front of Pep Boys, with a mad hot engine, cuz my temp guage stopped working. Luckily, the one I bought For $4.50, it was brass, and had the thredlocker, so I was good on that one. Guess Ill try and figure out what else is causing my sudden fuel economy to go down the tubes. Thanks for the help!

Sometimes the obvious is the most overlooked. What's your tire pressure like? I've owned two SL-1's and reached 150K+ on both before trading them in. The only two things I experienced that brought gas mileage down considerably was either low tire pressure (usually the culprit) or old spark plugs/wires.

my tires require 35psi, and thats where they always are. 1 week before all of this started happening, I changed the plugs, wires, pvc, fuel filter, ects, IAT, and both O2's. So I have no idea whats going on. I have an engine out of a 2007 cobalt ss, sitting in the shop, so maybe I'll just do a swap, who knows.:evillol: Thanks for everyones help!:biggrin: