i need some help guys/gals.... i am getting horable gas mileage. I dont know what is going on. i am getting like 200mile to a tank of gas... its starting to **** me off... it all started when i put a can of seafoam in my tank, i also put some of that z max bull **** in my oil. so i dont know what it might be. please help... do you guys think it would be my knock sensor? please help.

 

the knock sensor has alot to do with your gas mileage....might be just that, when i changed mine it was a real big jump in gas mileage.

 

First of all, is your car well mantained? Spark plugs, air filter etc...

 

Is your SES light on? Your post is vague...meaning it provides very little info for those who are trying to help you.

With what you said, it could be a number of things. Being that you mentioned did not mention an SES light, I guess you don't have one lit.

Perhaps your coils are dying?

What EXACTLY is your gas mileage? (Miles/gallon)

 

I am pretty sure all oil addatives are bad. So change your oil right away. Check your air filter and spark plugs. Does the car idle smooth and not hiccup or stutter? The seafoam might of fouled up the o2 sensors and that would cause bad gas milage. They usualy go around 80k miles or so anyway. So the seafoam might of been the straw that broke the camels back before the fly could land on it later. Also if you have over 100k replacing the KS would probably be a good idea also. Some advice on that is go to autozone or whatever to get the KS its like $120 and find somebody that has very very small hands.. a friend thats a midget or maybe a kid thats like 8 years old and have them change it. I had a drunk midget do mine was a piece of cake for him.

 

Also check O2 sensors, tire pressure level, and maybe add in a bottle of fuel system cleaner. Good luck.

 

thank for you all your help guys... my car is very well taken care of.. spark plugs, oil, premium fuel, airfilter, ect. I am going to try to knock sensor. since ive read that it did have alot to do with gas milage and so on. I dont have any codes what so ever. Well thank you for your help guys.