Fuel cut info...

[Spooled]

Here is a link to a page that I found when I was looking for info on the fuel cut problem. It isn't about the MazdaSpeed, but it is about the older Mazda ECU in the RX-7 turbo, and can explain why some people get fuel cut and some don't.

http://www.scuderiaciriani.com/rx7/fuel_cut_info.html

It is based on absolute pressure (atmosphere + boost) in the manifold, so if you are at a lower altitude, or the barometric pressure is high (ie - nice weather), then you have a better chance of hitting fuel cut. It is also based on RPM. I hope this helps some.

 

[Elderain]

I didn't think it was fuel cut, i thought that was more of a common misconception. I thought it was actually spark cut, someone said. Or am i confusing 2 different things here. Maybe it was late when i read that post, ill try to dig it up.

 

[Elderain]

here, it was discussed in this thread

http://mazdamp3.com/vbb230/showthread.php?s=&threadid=29747&highlight=spark+cut

 

[boostisgood]

I said it was Spark cut. This is info I got from a Mazda Engineer. He explained it in the most logical way. Why would fuel be cust, causeing the eingine to go lean, thus possibly causing detonation? It is Spark that is cut, thus eliminating the most common denominator in causing detonation. The point of heat to ignite the air/fuel mix.

 

[Elderain]

yeah what he said, i knew i heard about it somewhere

 

[nrcooled]

Spooled- The MSP uses a MAF sensor and not a MAP sensor. There is no way the ECU can tell what the pressure of the manifold is

 

[turboge]

Its a flow cut derived from mass measurement of air. Injectors are shut off. A spark cut will cause fuel to fill the cylinders and once the spark comes back cause be more prone to detonation or increased pressures.

 

[Kenetix]

This type of cut in the rotary was designed to cut spark to the leading rotor causing an overly rich condition. One of the problems with this system is that when an defensor was designed for it, the rotary is so tempremental to engine detonation most people blew their motors. This is the only reason the 13b turbo has a reputation for engine failure.