TERRIBLE GAS MILEAGE!! Really upset..

**My00Z28** · 02-15-2012, 12:13 PM

This is how I do my mpg. I drive till I fill up and reset my trip every time I fill up... So let's say by time I fill up I'm at 200 miles, I fill her up all the way and do the math like you... 200/##=##... That's the best way IMO... And driving city short trips is killer on mpg, all the stop and go... Take it on the highway to really test her out. My car in city is like 11-15 but I hot rod it often lol.

**My00Z28** · 02-15-2012, 12:15 PM

My daily trips are like 5 miles also so it barely gets to warm up lol

**flybird** · 02-15-2012, 12:41 PM

Lmao. I dnt hot rod. I keep my rpms near 2000-2700

**pajeff02** · 02-15-2012, 01:55 PM

Originally Posted by flybird

The reason I did it this way is bc its most accurate and ive noticed my gas guage sometimes dnt know where its supposed to be. (fuel sending unit)

Sulpher deposits can adversely affect the sending unit. Use Chevron Techron in your gas -- follow the instructions and run 12 gallons to a bottle. One or two treatments should clean up your sender -- if not, it may be a more serious issue.

**flybird** · 02-15-2012, 03:42 PM

Evry 3000 miles I am now using fuel cleaner to clean the system out. I use kroger 87 gas bc I get a discount evrytime

**0rion** · 02-15-2012, 04:29 PM

What kinda fuel cleaner are you using currently? You could also do sarge's 2 stroke deal and that will do a good job of cleaning it or you can also add seafoam. Will most likely take a few applications to get it clean like jeff said.

**My00Z28** · 02-15-2012, 04:41 PM

Originally Posted by 0rion

What kinda fuel cleaner are you using currently? You could also do sarge's 2 stroke deal and that will do a good job of cleaning it or you can also add seafoam. Will most likely take a few applications to get it clean like jeff said.

that 2 stroke thing was cool at first because of the money you save but i found if you fallow the amount he says to add it seems to be over treated because my car started to burn it visibly

**Too Fast** · 02-15-2012, 05:52 PM

So how have you checked your odometer accuracy? I am always doing it. Even before GPS, when I drove to N'Awlins and back in my '67 GTO powered by a .030 over 428. I'd watch the highway mile marker for 20 miles, to help pass the time and calculate exact MPG, watching the difference as the 1/10s would gradually get off track. With that car, I would go 103 miles indicated but actual was 100. You better believe I was putting in 16-17 gallons every ~180 miles, getting about 11 MPG. Gas was really cheap back then (1996, I think the year was), and I could fill the tank with 93 octane, get a Coke and a bag of snacks, and STILL get change from my $20 bill.

**pajeff02** · 02-15-2012, 05:54 PM

Originally Posted by My00Z28

that 2 stroke thing was cool at first because of the money you save but i found if you fallow the amount he says to add it seems to be over treated because my car started to burn it visibly

For every 5 gallons of gas add 1 ounce of oil. That makes it about a 640:1 ratio and I can not imagine that you would actually see or notice anything akin to burning oil. I run TC-W3 in every vehicle we own and have never had an issue.

**flybird** · 02-15-2012, 06:39 PM

.030 bored over? ? Have I been saying it wrong the whole time????? Holy sh¤t.. I said bored over .30 when the long block was replaced. Is it .030 ovet and not .30 over? Man I feel dumb

**35th-ANV-SS** · 02-15-2012, 06:56 PM

it's .030

**flybird** · 02-15-2012, 07:01 PM

Fml wow. No1 cared too tell me till now. I made an ass of my self.

**35th-ANV-SS** · 02-15-2012, 07:02 PM

It's not really a big deal man haha.

**flybird** · 02-15-2012, 07:18 PM

Ha ik just ive been saying it like tht for a year now.

**0rion** · 02-15-2012, 07:59 PM

everyone knew what you meant.....common error.

**0rion** · 02-15-2012, 07:59 PM

well.....everyone except you

just messing with ya

**My00Z28** · 02-15-2012, 08:15 PM

Originally Posted by pajeff02

For every 5 gallons of gas add 1 ounce of oil. That makes it about a 640:1 ratio and I can not imagine that you would actually see or notice anything akin to burning oil. I run TC-W3 in every vehicle we own and have never had an issue.

Yup I've had people telling me I'm burning oil when I used it and now that I stopped I haven't seen or heard anything? Maybe they were crazy or something.

**Too Fast** · 02-16-2012, 02:23 AM

Originally Posted by flybird

.030 bored over? ? Have I been saying it wrong the whole time????? Holy sh¤t.. I said bored over .30 when the long block was replaced. Is it .030 ovet and not .30 over? Man I feel dumb

No biggie. I didn't catch that until now, and besides, if you really had bored it .3 over, that'd be huge and without doing the math, it'd be like a 55 cubic inch increase, instead of about 5.

So in conversation, people usually say the engine is 30 over.

**FMBL** · 02-16-2012, 05:32 AM

Originally Posted by pajeff02

For every 5 gallons of gas add 1 ounce of oil. That makes it about a 640:1 ratio and I can not imagine that you would actually see or notice anything akin to burning oil. I run TC-W3 in every vehicle we own and have never had an issue.

I have been doing the same on 3 cars for a little over a year with no problems.

**Smittro** · 02-16-2012, 05:54 PM

So your engine is NOT bored, just has remanded specs..ok

13 mpg city is about right.

You should never expect the maximum estimated MPG's to be what you'll see..

The cold hard facts are they just don't get that great of mileage to begin with (though you'll hear different I think they need better math..

), and lumbering around town will chew up fuel quick.

Remember,, we're talking about a poorly breathing (specs & pics of actual N/A 3800II heads that I own upon request) , under powered engine moving a heavy car..

IAT trickers as the others say are just garbage.. They won't fool the PCM into making anything but later headaches.

Anyone claiming they're getting great results from an IAT modification is prolly a ricer or just a plain moron..

I've unpluged them on both OBD2 and OBD1 speed density cars with little or no performance or adverse effects except it did'nt like to idle sometimes..

Fuel mileage did suffer in a minute way, but nothing overly eye opening, and it certainly was'nt gallons

Secondly, you should not need to add any fuel/oil additives to a new engine, they are designed to run on octane ratings such as 87, but GM usually recommends better.

Additives don't "fix" anything, they simply mask a problem that will likely return upon it's discontinued use.

May even get worse..

You should get 100k++ out of the engine with just basic maintanances and repairs..

Millions before you have done so well over 100k without any mechanical knowledge at all other than gasing up, oil changes, and sometimes having it fixed.

Also additives won't "fix" the "floating" guage these cars have.. It's a GM thing..

It comes from a couple places.. From bad tank baffle design, to a poorly thought out cartrage fuel pump layout.. = You'll just have to live with it..lol