I have had the airflow sensor of my car replaced with a used one just to troubleshoot some CEL problems. The problems are gone after that but I noticed some power degradation especially during acceleration. My Rx-8 is the high power version. Could the problem be the sensor? At Mazda they told me that there are different sensors for the high power and low power cars. If they installed the sensor for the low power rx-8, could this degrade performance ?

maybe

The MAF sensor for the AT and MT are the same part number according to the RX-8 parts manual, so the dealer knows not what he says. If you have an oiled air filter element or oil in the intake pipe/filter area, the sensor element may be contaminated with oil. Clean the MAF sensor according to instructions found elsewhere on the forum. I think that is in the DIY section. Do a search.

You could (and should) clean your MAF, but it doesn't sound like that's it.

Sounds like plugs, or a coil.

S

The first step was to clean the MAF with ultrasound, second to replace sparks, coils and plugs and battery, the problem persisted so I temporarily changed the sensor and it is ok now but I notice some degradation in acceleration.
Do you think I should leave the used sensor and pay about $100 or get a brand new and pay about $500? If it is exactly the same and it doesn't affect performance then I shouldn't replace it but the dealer told me clearly:
1 for High power
1 for low power
1 for Japan imported cars
and that they are all different, they might fit but will affect the car

Well, the dealers service guy can tell you anything he/she wants. Print these pages out and ask why the MAF sensors for the AT and MT have the same part number. I'm sure he/she will have an answer for you. :yesnod:

I'd ask why the sensor is so expensive.....as i recall it is about $150 new??

I got mine 110 something a while ago.

Just a backup.

but your dealership is bsing you.

Thanks a lot, that was all helpful. As far as the prices are concerned, all prices for almost everything in my country is about 150-200% more expensive than the USA so don't compare them.