First i apologize for starting a new thread but after searching and reading for about 1,5 hour I was more puzzled than before.

I own a 6mt 2004, European specs 231HP RX8.
The car is stock with the exception of a cat-back exhaust.
I always redline the car more than once every day and i use semi-synthetic 5W30 oil (suggested oil for Europe by Mazda).

The car is giving me much trouble lately.

First 1 year ago at 15,000 kms i replaced the engine. Was a factory fault seal problem.

After that the car was running great until a 3 weeks ago and 20,000kms (sum 35,000kms).

The car "is stalling" from 4500rpms to 6500rpms and after it was ok. (Looked like a turbo lag except no turbo on the car).

I went 2 weeks ago for an oil change (scheduled) and read P0171 code.

We changed oil and oil filter , replaced the air filter with a brand new one and cleaned the MAF. Also the dealership gave me a new (European) ECU update.

Right after the update the car was very hard to start. Needs holding on the ignition for about 5-10 seconds (if you think this is nothing count slowly from one to 10) in order to start.

I went on my way and the car continued the same. I drove it over the weekend, same problem, then on Monday i skipped work and the car remained parked.

On Tuesday morning as i started the car got a steady CEL. I drove to the dealership and it was a P0410.

I described them about my revving problems and they suggested that a new catalytic converter was needed. The deleted the CEL code.

I drove the car same behavior and last Friday I left it in the parking. Surprise, surprise on Staurday morning as i started the engine CEL steady again. (with steady i mean not blinking, just on).

Went today in the dealership and this time i had P0410 and P0171.

The new Catalytic converter was installed today.

The told me to drive it for a few days and tell them what happens.

As I was about to leave, the head tech suggested that maybe coils need replacement and to return in September (after the holidays) for coils replacement.

Car still hard to start, car still "stalling" at same rpms.
I went for a drive, did some 60kms in "drive it like you stole it" mode and the problem remains.

Any suggestions , info , anything would be much appreciated. Thank you for your time reading this and plz remember that English is not my native language.

 

Your language skills are perfect vampyre. I understood every word.

Do they have the failed engine test in Greece? A lot on engines in the States are being replaced for various reasons. We all have our own theories. I would definitely do the coils as a precaution. Have you noticed any power loss in lower areas? Did the dealer check the plugs for fouling?

 

Thank you

There is no such test unfortunately. I have read the various threads for US.
The plugs were replaced twice in a 5 day period because after the engine replacement I had this problem and thanks for this forum I informed the techs about this issue. They had no idea and the main dealership was clueless.

But to answer your question , no they did not check the plugs. (I suppose you mean spark plugs).

No power loss under 4500rpms. Only around 4500-5000 and up to 6000-6500 the "turbo lag" issue. After 6500rpms car behaves great.

EDIT : Sorry, I forgot to mention. I have erratic idle rpms. Cold and hot the same. The idle is like 1000 jumps to 1200 jumps to 700 jumps to 900 etch.

 

If your cat died I would suggest having them check and change the coils and plugs. They should do this under warranty for you. Generally speaking I have seen failed coils as part of the reason why the cat. converters are dying. Your '04 probably has the old part number there is a new upgraded coil part number now that should be more durable...hopefully.

 

Hey i had the same problem mazda seed it was my headers but i left it alone and now it fix it self all do i dont redline asmuch and i also use 1 bottel of lucas syntech after 3QT of castrol syntech

 

P0171= System too lean ON 2 Fuel system
P0410= AIR system problem ON 2 AIR system

Maybe there is something going on with the intake. Try cleaning the MAF sensor.

 

Already done MAF cleaning. (its in first post).


Contacted the repair shop and we are going to change spark plugs and coils.'

As for the coils @shaunv74 i have the original ones on.

Lets hope this is it. I will update as soon as sparks and coils replaced.

Thanks.

 

I think that the following points should be checked

Your plugs and coils in connection with the dying cat causes your troubles.

Maybe the MAF itself gets faulty ? Check your air filter too.

Also try to use an injection cleaner and drive the car at the ranges where the problems occured. Maybe the fuel injectors needs a cleanup.

Greetings from Austria

 

Coils changed today 3 out of 4 were damaged, changed all 4.

As i saw where the coils are I understood the problem. Tsk, tsk, tsk Mazda put the coils on a solid metal plate. Great job for making sure they will overheat and burn.
Was it so difficult to have a panel with holes so that coils can "breathe" a little? :sigh:

Anyway problem solved will change spark plugs also to be on the safe side.

Thanks for all the answers.

 

Glad you figured it out, does it drive better now?

 

Certainly. There is a small hesitation around 6500rpms but car starts ok, idle is ok and after i took it from the dealership i did a 50kms drive just to check things out, changing gears at 9500rpms and car runs great. 5th gear 8500rpms 214kms/hour.
As i took it for a test drive from shop after coils replaced i was finding it difficult to not make the car go sideways. (i always drive with DSC off and many of the roads here are like glass. Before flaming me plz keep in mind the i drive rwd cars for the last 20 years and none of my previous cars had DSC and stuff like that).

The head tech said to drive it form something like 200kms and after a couple of weeks report back to them. If still there is "hesitation' will change spark plugs also.

I am thinking of changing spark plugs anyway (i have 4 new ones) just to be on the safe side.

Anyway shop is closing tomorrow for 2 weeks and i will leave for holidays (with the car) and return September 2nd. If there is still an issue i will update this thread.

Thank you for your interest.

 

Glad it worked out! Enjoy.