First off I would like to say I have searched for hours on this subject as it isn't the first time it has happened and have found nothing like this.

So I recently bought an 04 AT RX-8 GT (young and stupid, should have gotten manual ) with a little over 95,000 miles on it, now just over 100,000. Mazda service reports showed it had got a new engine replacement at 70,000 miles in 08/09.

In the 5 months of owning it, this is now the third time it has quit on me in the rain. The problem seems to happen whenever I go through puddles, not even an inch deep, and water splashes up under my car. The CEL will start flashing and acceleration until about 4000 RPM is VERY rough and it kind of sputters(I guess this is the way to describe it). I should mention it only takes one puddle and it starts doing this but after 4000 rpm its fine until it drops below that. After a while of trying driving to find a spot to pull over, it'll die as soon as i get to a good spot (thankfully). My brother did point out that the left side on the passenger floor became abnormally hot. I let the car sit for an hour or two and it runs smoothly afterwards.

The only things I have noticed like this while normally driving it, is when I have my foot on the gas and below 4000 rpms is there is a faint whistling sound, until I take my foot off the gas or rev past 4k. I have also noticed that the acceleration is slow to respond at times and it can sometimes take a second to turn over even on a warm start.

 

I am going to take a guess it's something with the Eccentric Shaft Position Sensor. It's located near the bottom pulley.

 

also could be O2 sensors.

also check spark plug wires are pushed all the way in.

 

how low is your intake

 

sounds like you are getting water in your intake.....

is the intake still stock?

if so, take out the air box and see if there are any water stains in the accordion tube

 

Its your maf sensor , when the water gets sucked from underneath, it wets the maf, as a safety precaution it will not rev past 4k unplug the sensor and dry it out and everything will be fine, I have the same issue in a car wash lol car dies so now I hand wash. Your maf should be damp if that'd the issue