bad mpgs and burning oil....bad shortblock?
06-02-2006, 12:22 AM
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bad mpgs and burning oil....bad shortblock? Could shortblock gone/going bad cause these two issues?? Ive gone from a 228/228 114 cam only to a f13/stock ls6 heads full bolt on car and my mpgs are still about 12-13 on the highway. Given the tune isnt 100%, but its no where near bad enough to cause those mpgs. i cant think of anything else that could be causing it. the oil burns about a qt a month or so...its not too bad yet, but im really beginning to think its the bottom end giving up 
06-02-2006, 12:28 AM
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mine went bad, the rings went away. I had unsmooth bores causing it to burn a quart every 300-400 miles. Only had 30,000 miles. Do a leak down, mine had a few holes leak down 26-27%. Good luck
06-02-2006, 06:34 AM
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I'd try the easy things first like changing the plugs, fuel filter, maybe running some top end cleaner through it. (you'd be surprised on how much this helps)
If you don't see a change, then do the leakdown and compression test. Maybe check to see if you have any injectors stuck open. If everything is sound after that, then it's all in your tune.
If you don't see a change, then do the leakdown and compression test. Maybe check to see if you have any injectors stuck open. If everything is sound after that, then it's all in your tune.
06-02-2006, 06:49 AM
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the only thing i havent changed is the fuel filter. Its done the same thing with the stock 26# injectors and the 42# svo's. Ive seafoamed it, no change. New plugs went in with the heads and cam install. Leak down and changing the fuel filter are the only things i have left. The overall performance of the car isnt that great either.
06-02-2006, 07:42 AM
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Originally Posted by ninobrn99
the only thing i havent changed is the fuel filter. Its done the same thing with the stock 26# injectors and the 42# svo's. Ive seafoamed it, no change. New plugs went in with the heads and cam install. Leak down and changing the fuel filter are the only things i have left. The overall performance of the car isnt that great either.
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06-02-2006, 11:42 AM
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Originally Posted by ninobrn99
which two cylinders?? 5 and 7??
1. 1% / 210 PSI
3. 1% / 200
5. 12 % / 185 (Washed ring, Maybe intake valve, slight valve leak)
7. 6% / 205
2. 5% / 200
4. 20% / 200 (Both valves leaking slightly)
6. 3% / 195
8. 1% / 195
