"LAG" at 7500 rpm's - RX8Club.com

04-16-2010, 09:26 PM

#1

rob1987

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"LAG" at 7500 rpm's

This is my second rx8

, my last one did not have this problem.. When revving to redline or in gear to redline the motor seems to "lag" in power for a second at about 7500 rpms. same spot every time.. Only thing done to it is an aem cai but it did it all stock as well.. Any input would be great. Thanks!

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04-16-2010, 10:09 PM

#2

Old Rotor

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Please give us the history on your car, year MT/AT,miles etc just anything you can add... The service it's had parts replaced. Have you Seafoamed it?

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04-17-2010, 09:03 AM

#3

rob1987

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the car is an 04. 6 speed. It has 62000 on it. I just recently replaced coils wires and plugs and seafoamed it. Other than that thats it. Its really weird

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04-17-2010, 09:17 AM

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heyarnold69

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I've had the exact same problem .. it was my fuel pump...

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04-17-2010, 09:28 AM

#5

rob1987

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dit it worsten over time? Did you ever find a reason as to why it only cuts out at about 7500? Think it could just be a fuel filter?

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04-17-2010, 03:58 PM

#6

Marky_Marc

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Is 7500Rpm not when the third port opens? your cat ok?

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04-17-2010, 04:39 PM

#7

Dirt_Nasty

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Quote:

Originally Posted by Marky_Marc

Is 7500Rpm not when the third port opens? your cat ok?

Pretty sure, I had the same problem on my AT 8, and it was the Dynamic intake port valve sticking.

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04-17-2010, 05:01 PM

#8

MazdaManiac

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APV opens at that point (actually 7250).
Many RX-8s exhibit a "lag" at this point due to sudden changes in the fuel map to compensate for this opening.
It will be worse in some gears than others.

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04-17-2010, 05:06 PM

#9

Brettus

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Quote:

Originally Posted by MazdaManiac

VDI opens at that point (actually 7250).
.

fixed

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04-17-2010, 05:09 PM

#10

rob1987

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Thanks for all the replies, as I stated I no longer have the stock intake on I have the AEM CAI. After doing some looking I found the MAF that came with the CAI (used) was covered in grime. I took that one out and put mine in and there is no longer what seems to be "lag". Thanks for all your help though!