I guess it could be a TB, but those usually show all around driveability issues if the TP sensor goes off rather just hard WOT only. Or at least I can't ever recall anyone reporting that before.

 

I'll see what I can figure out about my fuel situation this week. Thanks for the help

 

Just put the new TB on aaaaaaaaaaaaannnnnndddd, big surprise, same problem. But, it actually is a hell of a lot quieter which I'm happy with. Testing fuel pump soon

 

Well I just tested the fuel pump straight off its nipple. I jumped the tabs in the main fuse box. Pressure was 58 PSI and after 5 minutes it read 48 psi. So it passes Mazda spec

What would you do next? I'm starting to research the secondary injector set

 

check fuel pressure in engine bay as you are accelerating when afrs go lean .

 

This would be the best thing, but you need a special fitting that goes between the factory fuel line quick-disconnect fittings. It has a side port that you can connect a line and pressure guage to while also supplying fuel to engine. You can insert right where the connection where the metal fuel line transitions to the nylon fuel line on the side of the UIM near the brake booster

https://www.aeromotiveinc.com/produc...6-access-port/

BHR sells it if you have trouble finding one

https://black-halo-racing.myshopify....l-line-adapter

 

Thanks I already sent BHR a message, I'm hoping to get one by Saturday. I'd rather just get the right thing than jimmy rig up a hose clamp special.

EDIT: Nevermind his is $80

 

Well you'll need some other parts like a threaded nipple, hose and clamps, gauge or if you have an electric gauge a pressure sensor will screw in there instead, but require power wiring etc. it will also need a plug for the -6 port. Talk to Ray first, he may include that, edit: BHR site says the plug is included



.

 

Ray does in fact include it. I picked up a slighty cheaper one on amazon (1 day shipping) but ended up paying a bit more than BHR's price once I found out I needed the plug.

 

Unplug barometric sensor and go for a drive. You'll get a CEL but if you can give it full throttle that's likely your problem.

 

no dice, no dice.

 

.

 

Well, fuel pressure drops to 30 psi or less when wot

 

It's either the pump or the internal filter. I should be able to ship my spare pump out tomorrow, but I haven't put my eyes on it in a while. It should be out in the shop and I'm going there tomorrow.

 

Good thing you aren't boosted!

 

I know this whole situation could have easily been identified if I had a fuel pressure gauge but I hate the way gauges look in cars so I never wanted to get them. But I suppose having an inline removable gauge is definitely worth having.

I know failures happen on new stuff, but this thing is very low miles and I just switched to premixing idemitsu at the start of the summer.... wonder if that had anything to do with it.

 

That is quite unlikely. Much more likely it is just a **** poor pump

 

I know I'm just having a hard time digesting the fact I spent 300 and got almost zero life out of it.

Although I can't say I bought this car for its reliability

 

Check the filter under the pump before you jump to conclusions .................

 

More likely the fine filter around the pump than the sock filter at the bottom; the S2 pump module is different than the S1.

https://www.rx8club.com/series-ii-af...thread-261755/



.

 

Its a similar type of prefilter isn't it ?

 

If the sock filter at the bottom has debris you can see it easily because the actual filtering surface is exposed on the exterior side of it. The fine filter element assembly on the pump discharge you can't see at all.

 

Highly, highly unlikely. I use the same stuff and have for years, 8oz every 2 or 3 tanks now (stopped using it with every fill up).

I've never understood when people say this, my car has been nothing but reliable...

A faulty fuel pump could happen to any car any time especially when swapping OEM parts for aftermarket (I understand the S2 pump is technically OEM but not for an S1).

 

Air, fuel, and fire. This is why I agree with teams opinion from years ago that a fuel pressure gauge is one of if not the most useful gauges you can get. Mine has helped me identify issues a couple of times.

 

Well props to you for calling the proper diagnosis