I was on the competion's forum...no need to flame...and I ran across a VERY interesting topic about someone who pinned down the real issue of the 3,800 RPM hesitation...I truly believe its worth giving a look...



3,800 RPM Hesitation - The Secret You'd Be Scared of.......if you're still reading, its time to click bitch ;-P

 

For the ones who dont like reading, the fuel pump can work on 2 modes, low, when the car idles and high, above 3,000 RPM. When the computer turns on the HIGH mode, to send more fuel, there's some kind of slow down and the electric load is felt (aka hesitation). Turning the HIGH mode seconds before the 2ndary injectors (with RPM activated switch) would then "prepare" the injectors not to hesitate. Its poorly explained but I suggest you guys read along....youll be more intelligent

 

It sounds like he did a good job. BUT think about it...having to flip a switch everytime you plan on going above 4K RPM? Um...I don't know about you all, but my Rx7 rarely sees the bottom of the tach...and I wouldn't want to be reaching for a switch while accelerating or racing somebody...but still, he did a good job.

 

you didnt read everything....



rpm activated switch or you could set your pump to HIGH mode all the time.....but it would kill it pretty fast...3-4 years is what they say

 

I read it all, but really fast I guess....

 

I don't believe it. Sorry call me skeptical, The Fuel Pump has 2 wires. You can put a Voltmeter on it and read 12V all the time. There is aditional fuel pressure that comes from the Regulator at the end of the fuel rail. This is controlled by a soleniod to reduce emissions. Fuel Pressure raises 6-10 PSI with vacuum on the regulator.



Just pulling the Fuel Pump Relay will NOT kill the motor. The Fuel System is presurized, It will idle for quite sometime with the fuel pump relay pulled.



The ECU does indeed control the pump, but it doesn't vary the volume of fuel, Besides that the Fuel System has a return line on it. Any additional volume of fuel would go right back into the tank.