454 crusader backfires qt 2200 rpm

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CaptMike
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454 crusader backfires qt 2200 rpm

Post by CaptMike »

I have 91 and my Port engine wont throttle past 2200 in gear without backfiring and dropping rpm. It gets to high rpms fine in neutral. I am changing caps and rotors tomorrow. Any other ideas?
koviak
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Post by koviak »

Change your fuel filter. Popping thru carb is most likely not enough fuel to carb.
Dennis
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g36
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Post by g36 »

while your changing cap and rotor make sure the mechanical advance snaps back if you twist it and let go. if not or it hangs up then your advance isnt operating as it should and the timing will be off or nonexistant
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alexander38
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Post by alexander38 »

Good thoughts on both. If it still backfires check fuel pump and if its a Q- jet check filter in the carb
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JimmyM
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Post by JimmyM »

we had same thing after tuning her up...turned out it was the NEW set of wires....

Jimmy
sehord
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Post by sehord »

My Stbd engine is doing the same thing... 2200 Rpm I get a loud rapid popping sound..... I thought it was a rod or lifter knocking but now I think it is a backfire/pop... But I am not loosing any rpm after, I am just getting the popping at 2200 and up.... We ran some tranny fluid down the quadrajet to see if I had some carbon to break free but no avail.... wires and rotors are next in my book too.... did you ever find your problem?
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