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Backfiring and sluggish over 3k rpms/bad MPG

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Old 03-06-2009, 05:08 PM
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BladeX10
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Default Backfiring and sluggish over 3k rpms/bad MPG

Finally got my car out for alittle while after the 2 weeks of rain. Everything went fine until it went above 3k rpms. Then the car starts to backfire and it seemed really sluggish afterwards. Also. The car ran through 2.5 gallons of gas in like 8 miles and i was left pushing the car on the freeway.. lol.

Can someone tell me whats up?
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Old 03-07-2009, 01:55 AM
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93StreetFox
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Could be a number of things. Sounds like its misfiring. Give her a tune up. Now i notice your car is carbed i would definitely look into that. Maybe its time to rebuild that carb? I can tell you more with the more details you can provide.
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Old 03-07-2009, 03:35 AM
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BladeX10
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Wellll.. The car sat for a year and a half.. This was the first time driving it since i got it. Its still got everything it had on it a year and a half ago. I just dont know where to start heh


Also.. It only does that misfiring when its being driven. I can rev it past 3k in park and itll be fine
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Old 03-07-2009, 12:42 PM
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projectresto83
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auto or stick??? Do a tune up first, plugs, fuel filter, wires, cap, rotor, and check the timing then report back.
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Old 03-07-2009, 01:53 PM
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BladeX10
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Its an auto. Im in the middle of doing a tune up right now as we speak. Ill let you guys know
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Old 03-08-2009, 11:10 AM
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Jon82387
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sounds like either timing or possibly moisture in your distributer cap, hopefully the tuneup will fix it and check your timing while your at it.
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Old 03-08-2009, 11:12 AM
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wowvfast
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holley carb?
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Old 03-08-2009, 12:13 PM
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mjr46
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Originally Posted by BladeX10
Finally got my car out for alittle while after the 2 weeks of rain. Everything went fine until it went above 3k rpms. Then the car starts to backfire and it seemed really sluggish afterwards. Also. The car ran through 2.5 gallons of gas in like 8 miles and i was left pushing the car on the freeway.. lol.

Can someone tell me whats up?
if it's carbed , you might wanna check the floats and or needle and seat
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Old 03-08-2009, 12:29 PM
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BladeX10
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If the battery was dead as a rock.. Would that alter the performance? I had to jump start it and on the drive.. If i put the windows up or down.. The RPMS would bounce around. heh

Im about to go run up the store and get some new wires,cap and rotor, fuel filter, spark plugs. Anything else?

Where is the fuel filter located? I looked underneath briefly but didnt see anything
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Old 03-08-2009, 12:40 PM
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mjr46
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explain your set up ..is it a stock 84.5 mustang carbed set up???
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