Working on my 04 yesterday and when i put every thing back together it wont start... what's new.
Background:
Was drilling hole for turbo ecu
Took all of right side dash out
Only thing i unplugged was air bag and washer fluid container
I unplugged the positive side terminal on battery *some people say this is bad*
***this is that worst, when i took the washer fluid container out it tilted over and slowly dripped on the top of my ecu, which i had the cover off of, stupid me.***
I used as much paper towel as possible to dry everything off.

Problem Story:
I went to crank the car and it acted like it was going to start then it died down
Went to try again and the starter wont crank and the fuel pump wouldn't prime
The center console doesn't display the mazda rx-8 message or anything
The key symbol flashes

Then i went back and dried out the ecu a little more with paper towel, and when i went back now the fuel pump wont turn off, with the key out.
I pulled the relay and it didnt stop then i pulled the fuse and it stopped, i was worried it would flood the engine and i didnt want to go through that again.

Currently i unbolted the ECU and layed it out to air dry.
I'm hoping it could be a power relay that blew, any help would be appreciated

 

Drilling hole for Turbo ECU? You always disconnect the negative battery terminal and you never place a container of liquid over your open ECU.

If the ECU has water damage then it surely could be that but you would need to have someone who has a clue about diagnosing electronics actually test things.

 

I know i did alot of dumb stuff during this, and the water thing made me feel dumb.
i have a basic ecu reader if you think i could pull some info off of that
I have the greddy kit and i was reading off the install manual to have the emanage inside the car and the display and they said where to drill.
Again i realize what i did wrong with the battery terminal, just wondering with the symptoms if there might be anything besides the ECU like a relay
thanks for the input

 

First off, you don't want to use the E-mangle, it's ****.

Secondly, there is an access hole right behind the washer reservoir that just has tape over it so there is no need to drill.

Lastly, you need to know electronics before you can begin to troubleshoot this problem. You can start buy checking fuses but honestly I think you are in over your head already.

 

I've heard/read that its crap already and to get the COBB
I'm really trying to turbo it so i can sell it, gonna get it tuned for like 5lbs of boost
I think i saw the hole but it was the size of a dime or smaller and i dont think it was easy to get to from the inside. also i already drilled the hole

Do you know of any threads or places i can learn, i prefer to read and learn instead of giving up and paying a professional

 

Nah man, that thing is fried. You can try putting it out in the sun to dry it out. But if all you did was dry off the outside with a paper towel then started it up theres a 100% chance you shorted it. Water is conductive so you basically made a whole bunch of little jumpers to various resistors and wires within the PCM.

Again try drying it out in the sun, preferably when theres no rain in the forecast....

 

Also a turbo kit adds $-1200 to a cars value, please not the - symbol. Nobody wants a car thats turbo'd they assume its been beaten up and destroyed. They would much rather have a clean stock car that appears to be unmolested.

 

I would start by reading thru the major horsepower threads and stickies. But if you are trying to turbocharge it to sell it well you shoudl just sell it now because that makes no sense at all.

 

Drying in the sun might not get all the moisture out unless you take everything apart. If you applied power while it was still wet, there is a good chance you fried some components.
Drying in an oven might do the job, but if you are inexperienced, might make matters worse. PCBs are dried in specialized ovens with low/no humidity, but you have to verity the components within the board to ensure you do not exceed their thermal capacity.

 

I didn't want to suggest an oven as their internal sensors are usually 50* +/- of actual. But that would be the best solution.

 

I don't even know where to begin with this one.

Unfortunately you're in a world of hurt here with that PCM. It's toast, no real way to sugar coat that.
E-Manage is an absolute piece of ****. when it came out in like 2005, it's what people used because there were no other options.
Yes, cobb is an option but you need to find a used one because the very last RX8 Cobb AccessPORT was sold last month and there are no more being made. Ever.

But none of that solves your PCM problem.

 

You *NEVER* unplug the positive battery cable first.
The fuel pump not turning off means the fuel pump relay, and possibly other relays are stuck closed.

Disconnect the battery properly, go over your fuses and test the battery, and connect everything properly. At least you'll know it's all good before you bring a new ECU into the mix. I can't promise your ECU isn't fried, but do what you would do with a cell phone that got wet: dry it the **** out before you power it on.

 

Shady, you are correct, some components are very sensitive to heat, so unless you have a bill of materials, or have an idea of what components are on the PCB, don't do it.

Desiccant packets would work, but will take time to completely dry it out.

 

Guys i could use a quick response. There is a local mazda parts store that is willing to sell me a new ecu for 150 bucks, im willing to take the fall cause i screwed up
however my question is my ecu is a ND3Z and the one they are selling me is a N3H6 which they say is a direct crossover
is it worth it to go for and i there anything i should check first before reinstalling it so i don't fry the new one??

 

N3ZD, if that's what you mean. It should swap over.

The new ECU the antitheft system will need dealer programming to work together.

The dealer should be able to tell you if their ECU will work if you give them your VIN.

 

do you know what the difference is in the lettering?
the 18 881R,A,B,D,E for the N3ZD
and the 18 881J,H,G for the N3H6

Also the computer system messed up at the mazda place so they don't have one and i have to wait for one to ship now

 

Also if i were to buy a standalone ecu would i be able to bypass the immobilizer because i'm pretty sure my car went in to immobilizer mode which kinda pisses me off cause my key hasnt changed

 

The immobilizer is inside the ECU. The ignition barrell talks to it and it allows the car to start. If you go standalone you can do anything you want, but you'll need to figure out how to wire it up. They're not exactly plug and play.

 

If it was me I would dry out the ECU and the wiring.....and then try it. It is an expensive PIA trying to change the ECU. The fuel pump resistor is on that side...as well as relays for the air pump etc under the ECU as well.

 

I set it in minute rice for an hour and took a hair dryer to it, still didn't start
I just ordered a N3H6 ecu and am gonna call my insurance to see if i can have it towed to mazda, they said they could reprogram it for $240 or less which is 2 hours labor
Unless anyone knows places in washington that will do it for cheaper...
The ECU i found was used for $71 after tax

I really considered the standalone cause it would be nice to have and able to manage anything but i'm not looking long term at this car anymore because i want to get an rhd rx7 from canada

I hope this goes smoothly
Also since you guys have all bought rx8s what do you think a fair price i could sell mine for '04
6-speed with 104xxx miles, greddy exhaut and 18x10.5 wheels, all stock

 

wow, idk where to start. your car isnt worth much at all and even less without a rotary compression test. $71 for an ecu is pretty cheap. hope it works for ya, if not i have one sitting in my garage from an 04 6speed

 

About $3,000

 

I ordered a n3h6 18 1881J PCM and mazda is saying they can't program it

What PCM do you have?

 

n3h6. i cant make out the rest of the #s from the pic on my phone. it came out of a 04 6spd

 

Apparently the last numbers matter a lot because I gave Mazda an n3h6 and they're saying they can't reprogram it which is bs because it came out of 04 6 speed