Hello, i am the proud owner of a red 2004 gt rx-8. I love this car but it failed emissions here in colorado. Here are the stats hc levels were at 6.4 limits are at 1.2, co was at 4.5 which was good, co2 was at 438.9, and nox was at 3.333 limit is 1.5 so that failed too. So it failed hc and nox. Trouble codes pulled at the station were p0410(secondary air system malfunction) and p0031 upper 02 sensor. I ordered a new o2 tonight and was thinking about ordering coil packs and spark plugs. The owner i bought the car from was very deceitfull and pretty much lied about everything maitenance wise. I also pulled the air filter and it was full of oil, so i made a oil catch container as theoil was all over the intake side of the engine. This is my first rotary rx8 so i am trying to get advice on making this car pass emissions. The car starts and feels good, that is a slight miss in the rpm. Should i buy a new cat they are on ebay as a whole bolt on for 300 dollars. Sorry for the long posting just want to make this car perfect. Thanks in advance....

 

Search for the cat, there are only a few viable options. Most of the aftermarket cats will fail on this car. Try replacing the upper o2 sensor first and seeing if you can pass emissions then.

It is always a good idea to get plugs, coils, and wires changed if you have no clue when they were last done.

 

Thanks for the reply, i ordered 02, coils, plugs and bought a magnaflow direct bolt on cat sytem. I hope it will work. Anything else i should be looking out for? Thanks again.

 

Look for posts by hiflite999 he bought a specific magnaflow(I think) cat for $100 that has worked for him. A lot of aftermarket cats can be killed by the rotary VERY quickly. One guy killed his in a few autox runs iirc. So you might buy this cat and you could be buying a new one very soon. Also if you don't catch a bad cat in time it can cause engine damage.

 

its been my experience that the cat does 90% of the emissions clean up work.

there really is no other emissions equipment on the car, the air pump only runs on cold start. so once you make sure the engine isn't misfiring, it needs a cat to pass emissions.

with a new OEM cat emissions are really really low.

 

Yes ordered a cat yesterday. I am not gonna drive it untill all the parts have been changed. I dont want to toast theengine. Thanks for all the replies. I will keep u posted when i take it back to emissions.

 

I take it you live near the Denver Metro/Boulder area, if you live in Colorado and have emissions testing?

Its great that you bought all those parts, but had I seen the post earlier, I would have suggested that we install my spare ignition components on your car, and see if you pass the testing then.

Sorry that you bought a less than perfect car.
What year is it, and how many miles on it?

BC.

 

Yes i am in denver. They are strict here. Its a 2004 with 90k miles on it. I was just suprised that it didnt pass since its not that old. I paid 5200 for it but it has hail damage. Truthfully it probably has been run like that for sometime ,too much fuel going into the cat probably destroyed it. Previous owner just was not truthfull about anything.. oh well i will make this rx good again. I am looking for body panels to replace the hail damage? Where are you located?

 

Thank god i got a backup car a snow tank 91 audi 200 20valve putting out 300 horse. 180k miles on odo. Runs perfect. Yet ugly. Lol

 

That explains it, took the old cat off guesse what it was gutted. Anyone need a guted cat for racing free if you pick it up here in denver

 

If your getting high co's etc. Try this if you have determined your cat is ok:....Have 5 or 6 gallons in your tank prior to emissions test add 1 gallon of denatured alcohol (Home depot) and add another gallon or 2 to mix it up: you will pass emissions with readings like a new car. I have done it and it worked for me twice on 2 different cars.. At least then you can get through emissions and fix what ever may be wrong.

 

read everythinf before u reply ur 0.02 next time

 

My 2004 RX8 just failed emissions in Colorado because of HC GPM 2.0096/ limit is 1.2000 and NOs GPM 1.7462/limit is 1.5000. Equipment all passed, smoke passed. This car has a new/rebuilt engine and it only has roughly 2000 miles on it, if that matters. It sure matters to me since it cost a pretty penny! Bought the engine from Mazda. Any ideas? It runs fine, no misfire, no trouble cranking, even below zero.

 

CAT and/or ignition failure.