I have posted before about my sudden oil usage increase. Up to 18k miles, I was getting what seems to be the average of 3000 miles per quart. I brought the car in for the previous flash last spring when the car had 18k miles. When I got it back it idled roughly. The mechanic had no idea why. It then started using oil at approx. 1000 miles per quart. I now have 22k miles and the oil usage has stayed at the 1000 miles or less per quart. No changes in driving habits.

Also, I have noticed a drop in mpg. I was getting 18 to 19 mpg in mixed driving and 22 to 23 on the highway. Now I'm getting 17 to 18 in mixed and 20 on the highway.

Typically, I would expect a car that is now nicely broken in to have reduced oil consumption and slightly better mileage. The rough idle is annoying and is bad enough that it rattles the sunroof.

The dealer says nothing is wrong and won't even look at it. They checked the idle issue at the last recall and flash and said the new flash would fix it. It did nothing.

Any ideas out there as to what could be the issue? The car runs great and there are no oil leaks or tell-tale residue in the tail pipes. It has a new air filter and the oil is changed with Castrol 5-20 every 5k. I drive smoothly and do occassional high revs, but mostly shift around 5k.

At the spring dealer stop, when I got my car back it had a few miles put on it. I didn't think too much about it, because I figured they needed to test drive it. Is it possible that someone could have over revved the engine and done some sort of damage? I have not owned a rotary engined car before and I can't understand what is going on here.

 

chuck out my thread here, i had a similiar problem with my fuel economy at around 18-19k. cel came on one time, indicating catalyst below efficiency threshold, i spoke with my service writer, and we decided to clear it and see if it came back. it never came back, but right after my gas milage tanked. this is what we found when i took it in to get it looked at.

https://www.rx8club.com/showthread.p...86#post1008486

 

Link?

 

whoops

 

I think you need to take it to another dealer, even if it's out of the way. Contact some 8 owners in your area and find what dealerships they like. Also, be sure to document your complaints with your dealer.

I doubt it was over-revved as the rev limiter would stop that. The only way I know to over-rev is to downshift into too low of a gear.

 

Lurch 519, thanks for the idea. I have flooded the car twice and the CEL has come on and been cleared for the same catalyst problem. That was over a year ago and the CEL has never come back on. It doesn't explain the oil issue either, which frankly, bothers me more.

Georgia8er - this is my second dealership and I have been driving 40 minutes to get there. A guy from Mazda NA recommended them, saying they are the best in the area. The first dealership charged me $300 when my car flooded and had to be towed there. They wouldn't give it back until I paid. I wrote a nasty letter, but to no avail. I will never go back.