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J

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Discussion Starter #1
i wanna try something higher because my mechanic said i have some noise comming from the engine and yes i do hear it so i was thinkin of putting a higher gas in it to see how it will run with that but my car says it only takes unleaded fuel only? so i dunno if i can use premium or not? just wanna try it and see how it rides...if i use premium in a unleaded fuel car that means i wouldnt have to use a carbueter fuel additive or fuel system cleaner right?
 
M

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Discussion Starter #2
run a carb/fuel injection cleaner with a tank of AT LEAST midgrade unleaded. It could only help, and youll get better gas milage too
 

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Premium is unleaded also. You can't buy leaded gas anymore so yes. I recommend doing so once a month for that motor. It helps keep the injectors clean.
what type of noise are you hearing though?
If the mechanic says its a spark knock. that is a good sign of a few things...
Knock sensor not working (It senses ping knock and tells the computer to advance the timing enough to stop it)
Or the EST is faulting (Electronic Spark Control Module) Or the timing chain has alot of slop to it. so much so that the computer can't advance it enough to get rid of the spark knock.
That model motor you CAN adjust the timing so if it is a spark knock, then have the timing reset to "base timing" which is located on your engine label on the radiator support. When a timing gets sloppy the base timing can be off so the computer cant advance the timing enough to let it run properly.
 
K

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Discussion Starter #4
yes i doesnt matter youll just better gas mileage but the cost of it will even out so try mid grade gas first...
 
R

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Discussion Starter #5
Use Mobil premium. It will clean out everything. The knock you hear might be from dirty lifters, especially at this age. There was a secret recall on the cams in 305 engines made from 1975-1983. You might check with NHTSA web site for recalls on yours. If your engine has a lot of sludge in it, use a de-sludging chemical to restore lubrication to all your expensive lifters. Best one is "Power Tune" from Mercury boat store. Just spray contents into valve cover, drive gently for 2 days, then change oil to Mobil Synthetic 0W-40. drained oil will look like street tar. The foaming action from the butyl cellosolve (active ingredient) will have removed all the oil contaminants and your lifters will be quiet again!!! E-mail me back with your results!!!
 
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