Bad gas mileage!!!

[screamin86]

alright i do drive alot but i barley go 250miles to a full tank on my 98 camaro!!!:bs: i got it in july with 65,5xxmiles on it and i am about to trip 78k and so far i have changed plug wires coil packs and tires and regular oil change every 3kmiles and about 90% of the time i run midgrade gas and it seems to do better on my mileage than anything. anyone have anymore ideas on whaty i could do? i am filling it up 2-3times a week and its killing me!!!!

[youngsc]

Re: Bad gas mileage!!!

Switch back to 87 and check your cat for any blockages. Check your air filter and any other regular maintenance to make sure there is no unnecessary stress on your engine or car.

[screamin86]

Re: Bad gas mileage!!!

ive thought about just gutting the cat and gettign a o2 sim but i dunno if i should do that or put the 2 1/2 catco on that i pulled off of my 86 when i switched to true duals but ive heard that it will not work from some people and some say it will so i dunno

[youngsc]

Re: Bad gas mileage!!!

I haven't had any problems with mine so I don't know what to tell you there. I guess if it were me I would replace with anything that would be less restrictive so the catco and sim would be my first choice.

[screamin86]

Re: Bad gas mileage!!!

only thing is it doesnt seem any less powerful just poor mileage

[youngsc]

Re: Bad gas mileage!!!

I'm at work now so I don't have my manual in front of me. I'm pretty sure all it's going to say for poor gas mileage is to perform a routine tune up, change fluids and filters, make sure tires are properly inflated, etc. You haven't gotten any codes have you? Maybe seafoam it and see how it performs after that.

[badinfluenceRS]

Re: Bad gas mileage!!!

spark plugs...i'd say that would be the most effective part of a tune-up
air filter?
02 sensor maybe?

[youngsc]

Re: Bad gas mileage!!!

Oh yeah, I thought I read spark plugs up top. If you haven't done those def get those changed. That will make a world of diff. My car had 58k on it and all original stuff, I started getting a code and changed the plugs and wires. It's driven like a new car since.

[screamin86]

Re: Bad gas mileage!!!

yea plugs are the only thing i havent done yet and im kinda dreding it but i may end up doing it next weekend since i cant this week ive gotta go get my motor and work on the 3rdgen some. what is a good performing plug for the 3.8 i run acdelcos in my v8 thirdgen and i like em but expensive

[youngsc]

Re: Bad gas mileage!!!

I just got some regular plugs nothing special. My car was so bad it was stumbling so I needed anything. I wouldn't recommend anything with more than 2 tips as I've heard they cause more problems than their worth. If your dreading changing them because of the back two don't sweat it. I never changed the plugs on mine and it took about two hours and I didn't have to get underneath it once all from the top. I would recommend wearing gloves so your hands don't end up like swiss cheese though.

[CDNFB]

Re: Bad gas mileage!!!

Make sure you reach operating temp around 210F. If you are colder than that you are going to use more fuel.

Also, use your Air conditioning at the right times. Use only when necessary at slow speeds in city. Always use it at highspeeds on highway. Cars with window open at highway speeds burn more fuel than those with windows closed and airconditioning operating.

Change all your fluids to synthetic (power steering, engine oil, trans oil, diff oil) This is good for a few HP and better milage. (Please don't start the old leakage rant again!!!)

Keep your tire pressures high. The harder and narrower the tire the less friction and better gas milage.

Be aware of your driving habits. Hot-foot driving.....Bad. Anticipating traffic, picking routes with less stopping and higher more consistent speeds, and try to coast (foot off the gas long before needing to stop) as much as possible.

[CDNFB]

Re: Bad gas mileage!!!

Also, make sure you have a good front end alignment. Any mis-alignments will cause front tire friction....thus use more gas.

[youngsc]

Re: Bad gas mileage!!!

Also, use your Air conditioning at the right times. Use only when necessary at slow speeds in city. Always use it at highspeeds on highway. Cars with window open at highway speeds burn more fuel than those with windows closed and airconditioning operating

You've been watching mythbusters haven't you?

[screamin86]

Re: Bad gas mileage!!!

well right now i am not using the a/c thats for sure but the engine temps i alwasy thought were extremely low. i never changed the thermostat but im thinking whoever owned it before me may have put in a colder one. like the gauge always points at the first quarter mark or right below it

[CDNFB]

Re: Bad gas mileage!!!

Yeah, your going to need to get that temp higher to get a few more MPG. My car (in the summer) will run just a hair below the gauges indicated 210.

I get 320 miles per tank in the summer (in the city)

I'm only getting about 290 now (winter) but the engine temp doesn't get over 160 very often.