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Need help diagnosing a problem!

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Old 07-22-2007, 08:16 PM
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HamMach1
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Default Need help diagnosing a problem!

I get a feeling it's all tied into each other so let me explain...

First: when i start the car, sometimes, more times than none, it will slowly start up after it cranks like it will sound like it rose from the dead slowly.

Second: driving, under acceleration, the initialmoment i step on the pedal it feels like it jerks/bucks, and under deceleration it gives a violent buck like im tapping my brakes with a bit of force (but not slowing down...)

I feel that it's all tied in though. Anyone have a clue as to what I should check? I also get the typical "ticking" sound from the engine, I think it sounds most like a twig snapping. The reason I wish to have this problem figured out is because for one, it's annoying, and two, my warrenty's coming to and end Sept 15 I believe so I'd like to have this checked out and fixed before I end up selling my life to have it fixed lol.

Thanks ahead of time ....really.
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Old 07-22-2007, 09:13 PM
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oxfordgt
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Default RE: Need help diagnosing a problem!

check your fuel pump.
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Old 07-22-2007, 09:44 PM
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99mustanggt
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Default RE: Need help diagnosing a problem!

Could be your TPS,they tend to make the car buck when they go bad.
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Old 07-22-2007, 10:01 PM
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72MachOne99GT
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Default RE: Need help diagnosing a problem!

The bucking at acceleration? does that happen at mainly low low rpms??

if so, there is a chance its just old plugs.. i konw that i was getting a buck/chunk at low rpms when I gave it some throttle, changed the plug, and it certainly helped quite a bit....

as for the bucking on decel.... same story, if I keep the car in gear, but wind it down in gear, it'll buck at low enough rpms.. that hasnt gone away,, not sure what causes it,, but i would not assume it isnt normal

No guess as to the sound under your hood, unless its that nasty backfiring sound I experianced the other day...
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Old 07-22-2007, 10:35 PM
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HamMach1
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Default RE: Need help diagnosing a problem!

ORIGINAL: 72MachOne99GT

The bucking at acceleration? does that happen at mainly low low rpms??

if so, there is a chance its just old plugs.. i konw that i was getting a buck/chunk at low rpms when I gave it some throttle, changed the plug, and it certainly helped quite a bit....

as for the bucking on decel.... same story, if I keep the car in gear, but wind it down in gear, it'll buck at low enough rpms.. that hasnt gone away,, not sure what causes it,, but i would not assume it isnt normal

No guess as to the sound under your hood, unless its that nasty backfiring sound I experianced the other day...
Yeah it's the worst when I'm at lower rpms. If I'm up higher, it still does it but just gives a minor jerky feeling. I havea feeling a car isn't meant to be run this way and feel this way while driving.
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Old 07-22-2007, 11:01 PM
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72MachOne99GT
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Default RE: Need help diagnosing a problem!

Yeah it's the worst when I'm at lower rpms.
Well, if I'm in any gear just about , not usually first, but if I let the rpms get anywhere near 1300 or so while im decelerating in gear,,,

i'll get that bucking sort of feeling most of the time..

MY guess *and thats what it is, strictly a guess* is that its got something to do with the transmission, but not necessarily a problem,, just sort of something it does because of mechanics or something..

But the low rpm acceleration feeling like a cut out, or sort of chugging, .. like I said, it went away for me once I replaced my plugs..

*and it actually had JUST started to do it before my plug blew out, and now its stopped since I put a new one in... *
just a thought
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Old 07-22-2007, 11:26 PM
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HamMach1
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Default RE: Need help diagnosing a problem!

ORIGINAL: 72MachOne99GT

Yeah it's the worst when I'm at lower rpms.
Well, if I'm in any gear just about , not usually first, but if I let the rpms get anywhere near 1300 or so while im decelerating in gear,,,

i'll get that bucking sort of feeling most of the time..

MY guess *and thats what it is, strictly a guess* is that its got something to do with the transmission, but not necessarily a problem,, just sort of something it does because of mechanics or something..

But the low rpm acceleration feeling like a cut out, or sort of chugging, .. like I said, it went away for me once I replaced my plugs..

*and it actually had JUST started to do it before my plug blew out, and now its stopped since I put a new one in... *
just a thought
Ok thanks for the advice. Pardon my stupidity but when yall stay plugs you mean the spark plugs right?
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Old 07-23-2007, 12:00 AM
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BatMobile00
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Default RE: Need help diagnosing a problem!

do a tune up. plugs, air filter, fuel filter, pcv, all that good stuff. and if the problem still occurs, it is likely a bad coil
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Old 07-23-2007, 10:22 AM
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72MachOne99GT
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Default RE: Need help diagnosing a problem!

but when yall stay plugs you mean the spark plugs right?
We'll let it slide this time, just don't ask again.. lol..

But yea, spark plugs.


I hvae ngk* or nkg. .oh wait, theres a box next to me....

NGK TR55...they come pregapped, but still check them with whatever that little tool is * have no idea what its called* but it has the multiple widths to gap with just to make sure they are correct.
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Old 07-23-2007, 10:55 AM
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Brute03
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Default RE: Need help diagnosing a problem!

i've had the same thing for God knows how long, i've gone through 24 plugs, new fuel and air filter, new COP's checked the tps, new MAF and it still bucks when i let off the gas...... sort of feels like i'm getting bumped from behind. i think i'm just gonna man up and takeit to the shop [:@]
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