I'm trying to determine if I have a unique fuel starvation issue or if this is common to all RX8's before I tear into the fuel system on the car. Any input/experience would be appreciated.

- We have now had the problem on three different Solo courses this year with 180 degree or greater left hand turns including the Newport Pro event and a test-n-tune at Grissom this weekend. We determined that the car must have 3/4 of tank or more fuel onboard to prevent the fuel starve when accelerating away from the 180+ corner (occurs about 50 to 100 feet after the corner exit). It's consistent and gets worse with successive runs as the fuel load is reduced.

- The thing that really has us scratching our heads is, the car was run at 12 plus events last year plus a tire test which included skidpad work in the counter clockwise direction and no fuel starve was noticed running the fuel level down to 1/8th tank. The fuel starve appears to happen much sooner now?

- I realize it is common for the car to fuel starve once the low fuel light comes on and the pick-up is located in the lefthand saddle tank but I have not found any other instances of fuel starvation on the forum above 1/2 tank. The fuel gauge operation was also checked.

Any thoughts ?

Thanks-

Chris H
2006 RX8 Sport, Base Model

 

I never run anywhere near that much and have never had it

maybe a weak fuel pump or partially clogged internal fuel pump filter or bad pickup

 

Thanks Mark -

That's pretty much where I'm at. It's just strange that if their was a flow restriction or a weak pump that the car would still perform well under full throttle for extended periods (Pro Solo Launch etc). The only time it occurs is following the hard, sustained lefthanders...

 

We only had a problem if under 1/4 tank and long sweeping left.

 

^ Agreed,

You must be running a pretty hardcore tire/suspension setup to pull the kind of Gs needed for fuel starvation at 3/4 a tank.

 

Mine did it when the stock pump crapped out. Hasn't happened since the mazsport pump upgrade.

It got progressively higher in the tank...at first it was 1/4 tank..then 1/2...after a while it would do it at 3/4

 

I've always used the low fuel light as a "fuel starve indicator" when autocrossing, but I was suprised to find that I could fuel starve the car with about 1/3rd of a tank during long duration left hand turns at track days.

Yours still seems excessive Chris. I'd say it's time to call Mazdacomp and order a new fuel pump.

 

I have had it at 1/2 tank--replaced pump--no probs.
olddragger

 

Thanks everyone...sounds like a fuel pump R&R is in my near future.

Chris H

 

Check out the Mazsport fuel pump.

 

he has to stick with the OE pump due to class competition rules

be advised that you'll need a special factory tool to get the fastening flange that mounts the pump to the tank off and on, numerous threads on it for a search

 

Thanks...I found the thread with removal procedure, I'm going to give it a try without the specialty tool first. Hopefully, this is a one time repair.

Chris

 

be careful with the rubber gasket---its $50 to replace and make sure the pump doesnt turn when you are taking the top off.
its not hard to do.
after you get the old one out take it apart--you will be surprised.
see fuel starvation thread.
olddragger

 

Update - I installed a new, stock fuel pump sourced from the great guys at Mazdaspeed ($100 for Mazdaspeed members) a couple of weekends ago. Removing the plastic ring is a challenge without the factory tool, but once it's off, everything is very straight forward.

This weekend was the first opportunity I had, at a solo event, to see if the fuel starvation was corrected. With the fuel light just turned on, I am now able to make a 180 degree left turn again (at max g load) without starving out during WOT acceleration.

I can only assume that something internally in the pump malfunctioned or became restricted over the winter months.

Chris H

 

^ Awesome. Glad she's back in tip top shape Chris!

 

=( i wish i could be a mazdaspeed member so i can buy these pump at cheaper price XD...

 

i have the same problem, new pump below 3/4 of tank, my car starve

help!