2004 GT Manual
~65k miles - original engine
Premix w/ Idemitsu or Protek-R (whatever I happen to have onhand)
BHR Midpipe (thanks RIWWP!) and Ignition w/ MSD wires
AEM CAI
Plugs have ~200 miles on them (just changed them this weekend)
Oil catch can (installed this weekend)
AP w/ MM Tune
No CEL's
Re-Medy Water Pump and Thermostat

Last weekend I changed my plugs. Since then, in SECOND GEAR ONLY, i've been noticing an odd lull then surge in power roughly between 5k and 6k RPM when WOT.

Now, I don't have a VFAD valve as I have an AEM/Mazdaspeed intake. Apart from that, all else seems to be OK. We all know the VFAD opens at 5500RPM, however even with the VFAD I've never felt this before.

I'm a little out of ideas.

 

sense no one else will help i will try. You said this started after you changed your plugs this sounds stupid but pull your plugs back out and check them, check the threads in the block and make sure you put then in an tq to what the book says. I have seen this before with bad plugs and people that have put them in but didnt put them in all the way and didnt tq them.

 

Are the screens in your AEM still in place? I have seen them come loose and fall down in the pipe and cause all sorts of weird issues.

 

I'll definitely try. They were torqued to factory specs the first time but who knows. Thanks.


As far as I know. I'll pull the intake apart and make sure. Didn't think of that. Thanks!


Anyway, I just received my latest calibration from MM so if this still occurs after the flash, I'll try and log it.