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1987 mustang 5.0 misfiring while accelerating?

1719 Views 5 Replies 6 Participants Last post by  Carlson
i have an 87 mustang 5.0 i left it in my garage for a year or two and decided to take it out it again it only has 111K miles on it. but when i turned it on it would start for a minute then turn off by itself and i check the spark plus there were ok but i check the plugs and i seen one wire burnt so i decided to buy a new set and once i did it started and stayed on but it still misfires when accelerating like going into first then it gets worst when going into second but theres is no power at all its really sluggish. wondering what you guys think it is i really need this fix asap
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Should have just hid it in the garage so no one knows you own a girls car.
is it fuel injected or carburator if so your injectors could be clogged and same for your carb could be dirty. And when you leave a car sitting there you need to run it every other week to keep the gas from collecing particles in the gas tank and clogging your fuel pump and or injectors/carb try looking at the inside of the gas tank if it seems to rusty you'll need to replace it. And start from the source of fuel. Could also be a bad distribuator
Would suggest replacing fuel filter first. If you left car with full tank gas most likely OK. If not need fresh gas in tank. Also suggest oil and filter change, check inside air filter and exhaust for mice nests. Also most likely some lifters bled down while sat and will need to run awhile to refill, Check all fluids too, Hope tires aren't dry rotted.
Another thing to check (to go with making sure the firing order is correct) would be the electrical side of things ie HT leads resistance, check for a cracked rotor/distributor cap and make sure all inductors in dizzy cap are all clean and not carbon'd up. These things can often cause a misfire under load. Also check points gap and condensor should it have these, being an older vehicle.
double check your firing order to make sure its correct,should use the 5.0 ho firing order on it,sounds to me a plug wire is mixed up,does the car idle smooth or rough?
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