Ok so background on the car.

I bought this car about a year ago, its is a 2004 mt 6 speed, had 23,000 miles on it. I talked to the previous owner who said he babied the car... not good. I had the coils and sparks plugs changed about 32,000 mi. The car ran fine other than the normal rough idle at stops (which the dealer said was normal). Recently I got 3 codes with a check engine light. P0456 - Evap emission system leak (small), P0302 cylinder 2 misfire, and P0455 Evap emission system leak (large). I cleared all 3 codes and about a day later got the Evap emission system leak (large) again and cleared the code. I have in the last week or so noticed that under hard acceleration from 3rd to 4th it hesitates when going into 4th gear. Also when downshifting from 5th to 4th. I tried getting on the highway in 3rd gear and going as fast as I could. 3rd gear seems to have power loss and so does 4th. When in 3rd gear trying to redline it has troube in the 6,000-7,000 rpm range. Once I reach 7,000 rpms it wont go any farther. It seems to cut in and out and wont accelerate anymore until I shift to 4th at which point it still has a little bit of trouble. I still of course have the really rough idle at stops. Any advice. Im seriously at this point just questioning wether or not this car needs a new engine. Is it bad to wish death on this engine for a new one? Any help would be appreciated!

 

fuel pump?

none of those necessarily point to a bad motor.

 

I just had the evap leak code on my '07, they replaced the gas cap (check the bulletins, there is one about this) and found a sensor that was leaking which they replaced. You might want to try cleaning your MAF and run a can of BG44K through it.

 

I was checking the other day my intakebox (run a K&N filter) and my screens were black (assume from the filter's oil). I found today that besides ckecking the airbox it is very important to check the MAF and clean it if necessary . Most people use Carbon Cleaner. Do you just spray the cleaner and let it evaporate? or you do something different?

 

Finally got around to fixing the 8. I first took the advice here and replaced air filter and cleaned the mass airflow sensor. No good. I decided to finally take it into the dealership. They said that 3 of the 4 coils were bad and I replaced them. When I came back to pick the car up the guy said that they had test driven it and it still didn't seem like it was working right but to drive it for a week and see if it cleared up, but that I might need to replace the spark plugs.( Just replaced a year ago). I took it out on the highway and still got the same problems. I immediatley brought it back and told them to go ahead and do the plugs because he had said if after that it didn't fix the problem it might be time for a new engine. They said to forget about the plugs and they would run the test required by mazda to consider a new engine. I got a call later with them telling me my CAT was so clogged it was no wonder it wasn't working. They put a new one on and my god... I can't believe the difference. It's like a brand new RX-8. I've fallen in love all over again!

 

brand new cat is not cheap at all

 

Thankfully they paid, not me :-)

 

This is a good thread that indicates a Cat causing loss of power and the related bad coils.

 

Sounds like a nice Christmas present!!! Glad you fixed the problems!