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5th and 6th port question.

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Old Nov 8, 2008 | 09:27 PM
  #1  
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From: milly ga
GA 5th and 6th port question.

well i have that famous hesitation at 3800 rpm so i put new terminals on my battery(mine were stripped out really bad) and wired open the ports. Well it still isnt fixed so imma check all the grounds i was just wondering if whoever has done this if your idle got worse. now that i wired open my 5th and 6th ports when i first start it up it wants to die. anyone ever had this happen?
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Old Nov 8, 2008 | 11:23 PM
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From: Houston Tx
Yes with the Aux Ports open, this slows the air velocity down and hurts the fuel mixture.
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Old Nov 9, 2008 | 01:26 AM
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S4 RX7... I run mine without the 5th and 6th port sleeves/actuators... it just idles higher around 1500rpm... runs with 550cc secondaries.
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Old Nov 9, 2008 | 02:06 AM
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3800 rpm hesitation is due to a stumble in the primary/secondary fuel injector transition, which also happens to be at 3800 rpm like the aux port activation. It doesn't have anything to do with the aux ports however, so put them back the way they were. You're killing idle and bottom end power with them open at all times.
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Old Nov 9, 2008 | 04:19 PM
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the 3800 hesitation has very little to do with 5/6th ports. it's fuel related issue, sometimes cause by bad grounding. mazda released service bulletin regarding this issue.

the the simple things first

replace the fuel filter, inspect the fuel pump, check the fuel pressure, should be 37psi.

the most important injectors. send them for cleaning to rc engineering or witch hunter.
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Old Nov 9, 2008 | 06:47 PM
  #6  
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From: milly ga
sooo if my ground is good its my injectors?
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Old Nov 9, 2008 | 07:13 PM
  #7  
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From: milly ga
so whats next? all grounds are good
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Old Nov 10, 2008 | 01:22 AM
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From: milly ga
how do i smooth out that transition? i checked all the grounds and they seem to be ok
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Old Nov 10, 2008 | 03:16 PM
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There's no one answer to solve it 100% of the time. Most people will tell you to clean/replace all major ground points. Mainly, the ECU grounds to the block, and the body grounds (driveside shock tower & under trailing coil...). I can tell you this: my NA motor had a slight 3800 rpm hesitation under partial throttle, and no matter what I did to the grounds, it never went away.

Now with my new turbo engine, the hesitation is completely non-existent, which leads me to feel it was more ECU related than anything. My Rtek lowers the injector staging point to 3500 rpm, has new fuel maps & new solder points on the chip itself, which may be the reason for the improvement.

Bottom line: sometimes regrounding works, sometimes it's something else. No one can seem to agree as you can see in any of these threads:
https://www.rx7club.com/search.php?searchid=6277408
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Old Nov 12, 2008 | 12:10 AM
  #10  
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From: milly ga
i think you may be right because i was out driving and it seems the more i get on the car the less the hesitation but when i start it up and drive the next day it does the same thing
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