ECU/Ignition Replace
 

Replacing the ecu with matching locks including ignition lock and key.

While researching, I found some conflicting opinions as to whether will also need 'ECU rebuilt with "as built" data from Mazda.' .

Will I need anything other than matching ecu/locks/key in order to make the swap without having to reprogram the keys?

If you can find a 2004 ECU, you could have it flashed to the Race Tune by Racing Beat.

This removes the 'security' features, enabling any key (that fits the ignition) to start the car.....

....plus you get the nice 'crackly' race tune to drive with.

Worked for me!

$300 and the red security light flashes forever, but prolly cheaper than having the dealer dink around.

.

By 'security module' do you mean the keyless entry module?

eg:
https://cimg1.ibsrv.net/gimg/www.rx8...0c7f1fafbf.jpg

In other words, I'm wondering if I get the ecu,locks, key *and* keyless entry module from the same '04 mt, then swap into my '04 mt-could I forego the programming.

The ECU needs to be programmed to the other CAN modules in the car. Ones that come to mind are the power steering module and the traction control/DSC/ABS unit and the dash.

I had an issue with mine as well. Put in an ECU and reprogrammed it and all was good for a while.

( after the tech and I spent about 3hrs trying to figure it out...on the line with MNAO Techline a few times too. It is NOT that easy to do..sometimes you have to do steps multiple times to get it to work)

About a week after that it wouldn't start...and wouldn't connect to the WDS.

Dealer couldn't figure it out...after about an hour they said that the ECU was screwed again....so I took it home . Spent about 2 hours going over everything I could think of....and finally found the stupid fuse that supplies the power to the OBD connector had blown. After that everything worked properly and it started right up. Never did really sit down and figure out the reason...might have been the power source for the immobilizer module? Haven't had a problem in the last 6 or 7 years so not sure where the issue came from in the first place.

Thanks for that. .. let's me know what the situation could be and what I may be in for.
Looks like I've got some decisions to make.

What is yours doing?

i have an ecu if someone needs one

Have you checked shaft sensor signal?
Although that wouldn't explain the fuel pressure drop out...sounds like something is dropping the ECU signals.

Does it get worse when it is warm? or will it run long enough to warm up?