Hello,

After hitting what I believe was fuel starve on my RX8 on the track this week, I might as well replace the pump as a preventative measure. It would appear the S2 pump is the way to go, but I see on Mazdaspeed's site that there are four different part numbers for that pump:

N3H1-13-35ZE
N3H1-13-35ZF
N3R1-13-350
N3R1-13-35Z

These look to me like revisions. Does anybody have an opinion on this? I'm going to call Mazdaspeed to order the thing, and I'll ask them then. But I thought I'd also ask the membership here if I needed to look for a particular one.

The fuel starve I believe I encountered went like this. And I'm only uncertain that's what it was because, in seven years of competing in this car, I've never seen this happen. I ran the car on fumes when I autocrossed it.

I did two sessions in the wet on Blackhawk Farms, and only used about a quarter tank of fuel. The last session was allowed to run longer, and was dry. Because I had used so little fuel throughout the day, I did not keep an eye on it during this session. It appears to have gotten very low, very quickly. I used around a half a tank in 15-20min.

In a fast left-hand sweeping corner, where my data says I was consistently hitting 1.3g+, the car just died. I had no power at all, though the engine continued to run. I would get very brief bursts of power. This continued for maybe a minute as I limped back to the pits. After that it was fine. I filled the car up and drove it home three and a half hours.

 

Check the part numbers for it at MazMart and see if they match up.

 

unless you replace ur fuel tank to S2, S2 fuel pump is NOT a direct drop in replacement you WILL NEED to do modifications.

there is a thread about it , search.

 

nycgps is right, there is some modification required. The DIY is on fuel pump replacement thread. It is doable.

 

If you get the S2 left and right side fuel level sensors it's a direct drop in swap. I did a short writeup documenting it in the thread, however be aware it may throw off your gauge. The S2 has a gallon larger fuel tank. Not a huge difference on the gauge but if you run your car below quarter tank just be aware.

 

You asked...

N3R1-13-35Z is S2 Complete Fuel Pump assembly.

N3R1-13-350 is S2 Pump Motor Only.

 

The diagram on the website clearly shows that too. It's only a partial solution. It's also not a legal mod for autox below Street Prepared.

It made more sense for this to be added/moved to the S2 pump thread, but whatever.



.

 

really ? sweet.

but I gotta check my 2nd 8's fuel tank to see if it's melt, cuz for some reason I can smell fuel in the rear wheel well, the 8's ECU was never updated to the newer version, hell the plug on the tranny even melt because of heat.

if it's not melt, I will just get new sensors, if it's melt, well, gotta get a new tank, S2 it is.

 

Yeah the sensors direct fit into the series 1 from the series 2 tank. They shouldn't melt, their at the bottom of the tank and don't take any heat.

If you're gonna be in NYC any time soon I have the S2 right side sensor with the fuel hose, I didn't use because my fuel ring on the right side didnt budge, so I stayed with the S1 sensor on that side.

You can have it lol the dude who sold me the S2 pump threw in the sensors free.

 

Sweeet

but blah, I am not in NYC right now, won't be back for another 4-5 months

Naw, I was gonna say my fuel tank might have deformations due to heat, it's part of the original 420F recall(whatever it's called) , asks dealerships to check the top of the fuel tank for deforms and melt connectors right by the CAT, I have a melted connector, and now I sorta can smell fuel in the rear wheel well, so I *think* there is something wrong with the fuel tank. this AT 8 has been sitting for 2+ yrs, had no time, but now Im starting to work on it, might as well try to fix everything before I take it back on the road.

I probably just gonna grab all the S2 assembly locally. thx tho