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my baby is sick...starts missing at full throttle

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Old 02-13-2009, 06:46 AM
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yoxtheox
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Default my baby is sick...starts missing at full throttle

runs fine but when i get on it, it falls on its face. starts scattering and missing, my guess is the tps sensor. i have a new throttle body (bbk) on the way and it comes with the sensor. but i would like your 2 cents. thanks a ton
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Old 02-13-2009, 07:53 AM
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OneGearhead
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how much power is your car making? my buddy has a fully built 331 in his car, and this happened to him at one point. he did some research and it turned out that it was cold air kit. he upgraded his bbk to an afm power pipe and it fixed the problem. i guess the bbk couldnt move as much air.
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Old 02-13-2009, 10:02 AM
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Riceinator
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Does it do it all the time, or after the it gets warmed up?
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Old 02-13-2009, 04:28 PM
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Snake
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I ran my 93 for awhile (accidentally) without an air filter. My car started doing the same thing, regular acceleration was fine until I got on it, then it would bog down and backfire and do all kinds of nasty things. This lasted for almost 2 months until a friend of my dad's suggested looking at the mass air sensor. Took a look at it and it appeared to be fine at first glance, but I figured I would GENTLY (and I mean gently) take a toothbrush and some alcohol to the wire inside the mass air sensor. I couldn't tell at first that it was dirty, but after seeing how bright the wire got I realized it was just dirt buildup on the wire that caused the problem, for me at least. After cleaning it, it ran fantastic again immediately.

Oh, and, I put the air filter back in.
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Old 02-13-2009, 07:10 PM
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mjr46
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Originally Posted by yoxtheox
runs fine but when i get on it, it falls on its face. starts scattering and missing, my guess is the tps sensor. i have a new throttle body (bbk) on the way and it comes with the sensor. but i would like your 2 cents. thanks a ton
has it been tuned up lately?? cap, rotor, wires and plugs if not
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Old 02-13-2009, 07:16 PM
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yoxtheox
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thanks for the tips.....just a little more info..it only does it at 3000 rpm and up
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Old 02-13-2009, 07:31 PM
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mjr46
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spark travels a path of least resistance to ground ad under load..ie WOT FIRING VOLTAGES WILL RISE and if the weak link are oldwires/high resistance in them, then spark will jump out of the insulation and ground out on the block
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Old 02-13-2009, 08:23 PM
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yoxtheox
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i have fms wires on it....fairly new
but i will get a new cap and rotor
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Old 02-13-2009, 08:53 PM
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I'm having the exact problem but I have replaced every thing in the ignition system and the fuel system minus injectors rails and lines.
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Old 02-13-2009, 09:39 PM
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mjr46
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Originally Posted by Mabii
I'm having the exact problem but I have replaced every thing in the ignition system and the fuel system minus injectors rails and lines.
clean th maf and run a koer test
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