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Unhappy Missing at 4-5k rpm under load only.

Am I looking at an afm thing?

The 'sweet spot' has a hole in it.

In especially second and third gear, with the pedal depressed OVER half way, I get dead spot in acceleration.
(complete dead spots like nothing)

Doesn't happen with the clutch in.



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Old 06-14-2004, 04:27 PM
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Speed and ref. sensor connections (mine are questionable)??
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Old 06-14-2004, 05:43 PM
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Ok, nother hint...

Doesnt really happen in 1st that I notice.

Usually right around 4100rpms.
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Old 06-15-2004, 05:58 AM
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Check that afm. A guy on the "other" forum had that problem and it was solved by a new AFM...I say see if you can borrow an AFM to check your car with.
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Old 06-15-2004, 06:33 AM
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Sometimes a flat spot is a vacuum leak where the intake bolts to the head. Also check the o-ring between the throttle body and the intake manifold.

Here's another potential; the tach. Gordons was bad and would disrupt the coil signal at certain rpms. His problem also impacted his smog testing showing the car running rich.

Sticking flap in the AFS would also be a problem.
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Hugh - So Cal 83 944 Driver Person
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When was the last time you changed your timing and balance belts and/or cam chain and tensioner?
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Old 06-15-2004, 07:05 AM
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Hey.....I think you are on to something..

loose bolts from intake to head.

I just had a engine noise increase as well (normal rev noise). I did my head work a year ago and had several loose cam cover bolts a few months ago.

Torque to bolts I will........





--kinda leaning against afm since it is only in certain gears and under load....wouldn't it do it in neutral as well?
--oring 1 year old
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Old 06-15-2004, 07:58 AM
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What about the ignition wires? My roomate had a similar problem and that fixed it.
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Old 06-15-2004, 08:02 AM
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The "under load" is much different than "in neutral".

This is why the smog tests use a dyno.
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Hugh - So Cal 83 944 Driver Person
NOT a 'real' Porsche -- Its Better!!!!
When was the last time you changed your timing and balance belts and/or cam chain and tensioner?
New Users please add your car's year and model to your signature line!
Never break more than you fix!
Old 06-15-2004, 08:59 AM
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So AFM could still be a factor?

Or maybe the good ole flap?
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Old 06-15-2004, 09:45 AM
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Could be that the harmonic resonance of the pulsing air flow through your specific intake is causing a standing wave at those exact rpms that interferes with the ballistics of the AFS flap.
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Hugh - So Cal 83 944 Driver Person
NOT a 'real' Porsche -- Its Better!!!!
When was the last time you changed your timing and balance belts and/or cam chain and tensioner?
New Users please add your car's year and model to your signature line!
Never break more than you fix!
Old 06-15-2004, 01:25 PM
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I can buy that.



First torque the bolts I shall....


Next

Check the AFM I will...
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Old 06-15-2004, 01:58 PM
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