cars jerking under load

BryanDyer

New Member
Jun 13, 2012
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Georgia
just replaced a bad afm so the car runs much better now
idles perfect timings perfect runs perfect but if I get past about 3 lbs of boost if I was it on or If I just stomp it I can't boost the car jerks really bad loses power same feeling as when you try to boost with a knock sensor code
my vacumm is also perfect right at -19-18 psi at idle
just wanting to hear what you guys think it could be
changed plug wires plugs checked coils
but have not checked for a boost leak yet which I know is a possibility but not the only one
much appreciated for your input thank you
 

IndigoMKII

New Member
May 9, 2011
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Madison, Virginia
Okay well, are there any CEL codes? Does the CEL flash when it 'jerks'?

As said before, check for boost leaks and CEL codes then return with more information.
 

BryanDyer

New Member
Jun 13, 2012
654
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Georgia
checked for leak
no leak
I don't think this is a leak issue when I stomp it it like loses all power but if I eas the boost on it doesn't do it so I'm wondering maybe my igniter or the coils
 

BryanDyer

New Member
Jun 13, 2012
654
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Georgia
yes I know
the way it jerks though seems like a fuel cut and it does it around 2800 rpms that's why I don't think it's a boost leak
like eiter a fuel cut spark or igniter proble.
I was driving home left from a light and it did it for about 4 seconds in 2nd gear until I let off the gas just no power not bogging but just dropped all rpms no power until I finally let off and then got pack on the pedal to go I just have no idea
 

IndigoMKII

New Member
May 9, 2011
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Madison, Virginia
We just need a big stick to smack some of these people with. People come here asking for help, someone offers a few words of advice which is then instantly ignored and further needless information is delivered.

OP, check your codes as stated many times before.
 

BryanDyer

New Member
Jun 13, 2012
654
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Georgia
pressurized all the piping from the inlet to the turbo
funny thing though I was driving today and it didnt seem to be jerking so I boosted in 4th and it ran fine hit 15psi
went around the corner downshifted to 2nd and boosted all te way through 4th no jerking hit 15psi
it seems the car has fixed itself I really do not know how or what caused it but oh well no problem now haha