Canucklehead

As the title says, I have an 04 that just had the engine and wiring harness replaced at a Mazda dealership. As for aftermarket parts, it has a racing beat intake and cat back exhaust, nothing else. The drive home was fine, but the next day, I took it for a drive and when I pulled up to a stop sign in neutral, the engine died and I had to restart it (this symptoms are the reason I got a rebuild, I took it in and was told bad compression was causing it, the compression numbers backed that up so I went for the rebuild, issues persisted so i got a new wiring harness). Some more details; the idle is steady when first started, then slowly gets more choppy as it heats up, then finally sputters and dies unless my foot is on the gas. It’s backfiring sometimes just from revving it up to 3-4K which from what I understand is not good. Every now and then I think I may hear a hiss from the engine bay indicating a leak, but I’m unable to find an exact source or even be sure if it is a leak I’m hearing.

The engine light is still on and I am getting the following codes:

-Secondary air injection system control “B” circuit low (P2259) (this one is reading twice)
-Evaporative emissions system leak detection pump control circuit high (P2402) (also reading twice)
-Intake manifold tuning (IMT) valve stuck open bank 1 (P2070) (Again, two readings)
-secondary air injection system (P0410) (yet again, double readin)
-catalyst efficiency below threshold (bank 1) (P0420)

before I get roasted for this post, please believe me when I say I’ve read through these forums as well as others. I’ve been on quorra, yt, you name it, I can’t find someone in the same situation as me. I’m willing to put more money into this car to get it running properly but I need to know what to tackle first, if it’s worth it at all. A

CaymanRotary

If the Mazda dealership did the rebuild, can you not just take it back to them? If I dropped God knows how many thousands to have them fix the entire engine and wiring harness and it only lasted one day I’d be mega pissed. I’d probably rain hellfire on their asses. Is the car straight piped or do you still have a cat? Probably also have a vacuum leak in the intake manifold. Best way to find it is with a smoke test. If you still have a cat, it’s likely clogged which will ruin even a brand new engine. I find it hard to believe though that Mazda would make such a rookie mistake but these are strange times...

Canucklehead

Well, sort of funny story, the car itself spent almost a full year at the dealership with multiple long delays due to faulty parts and other mishaps. I do plan on taking it back there but I at least want to have a better idea of what could be the main issues at hand, that way there’s no chance they could mess up a diagnosis, or run improper tests causing another long wait (I won’t say I’m happy with how they’ve handled it but at the same time, my rx8 is one of maybe 3 I’ve ever seen in the area, and one of the only ones to be serviced there).
Also, it is not straight piped, stock exhaust up to and including the cat, racing beat kit after that. I appreciate your insight about the intake leak, I took a quick look over the whole engine bay a few days ago but I’ll take another look there.

CaymanRotary

Have your catalytic converter inspected too. It's likely clogged which probably ruined the new engine. I would have a compression test done first just to confirm if the engine is toast or not. If the engine is indeed ok, you will then want to have the cat taken off the car and inspected. Those would be my first moves. It's not worth fixing anything without first confirming the engine is ok. Otherwise you are basically flushing more money down the toilet.

dannobre

iTrader: (3)

Reset the ESS sensor profile and see if that helps. I have seen 2 dealer swapped motors that they didn't reset the shaft profile and they ran like crap until it was reset

The other codes are SSV and and air pump/CAT related so as suggested I would check the CAT as well.

Check and see if the SSV actuator/valve moves freely when you push on the arm.

I would take it back and bitch

Why did they think it needed a wiring harness? Seems a bit strange unless someone pinched it or broke something pulling the engine

chanrx8

So, if you remove the CAT and have it straight piped, will it sound very LOUD? Does the RX8 require a CAT or not?
do have this P2070 code as well and fairly newly rebuilt MT 05 engine (<5k miles).

CaymanRotary

Yes, it will definitely be louder. Your best bet is to add in a resonator to the straight pipe to make it sound more normal.