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Hesitation at 7k?

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Old 06-01-2008, 07:06 PM
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Hesitation at 7k?

Hey guys,

I was Motorsports Ranch today, and I noticed that my car was hesitating momentarily at around 7k rpm under hard acceleration. Nothing huge or enough to upset the car, but enough that I noticed it. I've run several track events this season and never noticed this issue before. Other than that, the car ran fine, even in the 90+ degree heat.

The car is basically stock engine-wise, with nothing but an "Isley special" exhaust system. Running name brand 93 octane fuel, 10w40 dino oil, no premix. Any idea what might be causing the hesitation?
Old 06-01-2008, 07:16 PM
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Ports open up around there.

There's a normal dip there.

Get the Access Port from MM. Problem solved.
Old 06-01-2008, 08:15 PM
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Originally Posted by Razz1
Ports open up around there.

There's a normal dip there.
+1 Last intake ports open up at 7,250rpms. I've noticed that slight hestitation as well...seems more pronounced when the a/c is running for some reason.
Old 06-02-2008, 01:10 PM
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never had it that I can say
Old 06-02-2008, 02:33 PM
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Do you notice any difference in the sound coming from the front of the car? Like a gurgle or popping sound? When my car needed new plugs it would misfire and lose power around 7k and make a strange noise.
Old 06-03-2008, 06:41 PM
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Originally Posted by SHOWOFF
Do you notice any difference in the sound coming from the front of the car? Like a gurgle or popping sound? When my car needed new plugs it would misfire and lose power around 7k and make a strange noise.
No different sounds or misfires. Car pulls strong to redline - I personally have just felt the slightest pause as the tach sweeps past 7,200rpms.

FWIW, my car has 26K miles and is an '06 (comes from the factory with the revised plugs). Plugs should be changed every 30K miles, so I'll be changing mine anyway this summer before Solo Nats.

Last edited by chiketkd; 06-03-2008 at 06:44 PM.
Old 06-16-2008, 10:49 PM
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it could be the fuel filter???
Old 06-16-2008, 11:55 PM
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Fuel pump.
Old 06-18-2008, 01:41 AM
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I doubt it's anything faulty. I noticed it some time ago. Just a slight hesitation at WOT. Seemed to happen right after my shift to 4th if I remember correctly. Didn't notice it at Buttonwillow a couple weekends ago.
Old 09-09-2008, 09:55 AM
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Swapped in new OE spark plugs this weekend and the slight hesitation at 7K rpms is gone. Car pulls strongly to redline -- especially in the 7-9k rpm range.
Old 09-15-2008, 04:09 PM
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^glad you found a fix. I also had a similar issue but it turned out to be the coils. I also swapped out the plugs and plug wires when the coils were done.
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