Stumped: Oil burning and Gas mileage

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Stumped: Oil burning and Gas mileage

Postby 98_Q45 » Thu Apr 26, 2018 4:59 pm

So for the past week I’ve been doing long highway driving cross country mixed with city. Today I checked my oil this morning, and I was a quart and a half low (oil only barely registered on the dip stick, but a full quart bought it up to a few notches below the full line). This is over a period of a few days and my last half quart re-fill was maybe 600/700 miles ago. Even if that’s considered “normal”, I’m adding oil every 500-1,000 miles to keep from running low. The smoke from engine also seems to still be there, but this is after I’ve already replaced valve covers. I can only see a drop of oil every few seconds under the car with engine idle.

Gas mileage also seems a bit off. I changed fuel filter and both Pcv valves. It seems when starting up cold, fuel smells fill the engine and I get some rpm/engine rock.

I’m hoping to get a new compressor in before summer, but I’m thinking if it’s sucking down this much gas and oil without a/c running, how much more will it take? These gas prices don’t really help, I’m barely getting full tanks with $30.

Otherwise, it’s doing good on the road for the most part. Just can’t do over 70/75 before oil and gas just starts evaporating. Doesn’t help when mofos all around are doing 85/90.

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Re: Stumped: Oil burning and Gas mileage

Postby macgiver » Thu Apr 26, 2018 5:12 pm

mac , almost sounds like drippetty leak got too low , then those long trips kinda ruined your engine,unfortunately topping it off a little late ? Through no real fault of your own , when motor reaches "critical mass " so to speak ( deterioration imminent) we're not always on top of it - checking oil & such :tisk: Only other thing comes to mind - who if anyone has access , worked on , changed motor oil etc.? Sabotage / Fatal error- not such a long shot. Ie. sand in the block / LubeBoy forgot to put oil & drove ,
hears engine CLUNKING -NOW puts oil in ? :facepalm: 1998? - Almost forgot -How many miles? A/C may be a moot point here hate to say.

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Re: Stumped: Oil burning and Gas mileage

Postby DurableOilAMSOIL » Fri Apr 27, 2018 12:58 am

What type of oil and filter are you using?

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Re: Stumped: Oil burning and Gas mileage

Postby Q451990 » Sat Apr 28, 2018 8:37 am

If there's visible oil dripping under your engine, you have a heck of a leak... I'd clean everything with a foaming engine degreaser and look for the source.

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Re: Stumped: Oil burning and Gas mileage

Postby 98_Q45 » Tue May 08, 2018 9:01 pm

Hey I’m back. Forgot to come back and read the replies. Ya know...being on the road and all.

For one, my engine isn’t toast lol. It’s still going strong. And it’s fairly quiet except a hint of ticking noise that you’d have to really listen to. But nothing that seems to affect performance. Now, idk about the prior owners..but I’ve never let it run more than 2 quarts low. I overfilled it once before because the Dp was bone dry. But I threw in 3 quarts and it ended up being about 3/4 quart overfilled. And when it’s overfilled, it really smoked up!

I been using syn blend high mileage of all different brands. Purolator boss/pure one filters. But my upcoming oil change, I’m using Mobil 1 high mileage, as I find the dirtier the oil gets, the worse it smokes. But it’s always a clear white smoke, only visible when car is off and fan isn’t keeping it in the engine.

Today it smoked up pretty bad. Hit 90 degrees and 90 mph..not trying to burn the car up either

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Re: Stumped: Oil burning and Gas mileage

Postby moe7404 » Mon Oct 08, 2018 6:25 pm

i hope iam not to late. try some Marvel Mystery Oil. in the fuel. 4 oz to 10 gal. MMO is very forgiving of the amount you put in. hopeing to seal the piston rings.

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