Rebuild or New Engine?
 

My rx-8 has been sitting for 4 years in garage. I drove through water and it never started up and did not have full coverage. At the time, one shop told me they could fix it for 500. Brought it back next day and the guy who was going to do it no longer worked there was fired. Another guy told me the engine was bad. What all would I need to change? Could I do a rebuild with water damage. What all would I have to replace since it has been sitting for a while?

There's no way to answer that from here. You need to properly diagnose the problems it actually has. It could be as simple as dead coils, or as bad as cracked metal parts.

Pull the spark plugs and see if there is oil, coolant or gas on them. If they're dry, that's a good start. Put fresh gas in it, charge the battery and report back on what happens when you try to start it.

In most cases with these engines, a rebuild requires one or more of the big parts to be replaced. Your best bet, if it is bad, is to get a rebuilt one from a professional rotary rebuilder. New engines don't exist.

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Thanks for the info Loki. I will try that first.

In my opinion, any rebuild costing less than $2500 is highly suspect. It may run but it won't be up to full strength and may need to be rebuilt again soon after.

At a minimum, assuming all the metal parts are in good condition, the parts alone are going to be around $1000. This is almost never the case.

If your engine ingested water then there could be significant damage just from the water being in there and causing the combustion chamber to rust over four years. If this is the case, just get a remnaufactured engine from Mazda.

If your car is a 2004-2008 6MT, search for this part number: N3H3-02-200R-V0 (you should able to find it from a dealer for <$3k + core and shipping).

Thanks man, yes, it has been a while. Would you happen to have part # for 2008 auto?

Mazda charges more for the auto rebuilt engine than the manual, seemed like it was around $700 more or so

Ok thanks. I'll look into it.

Yeah, it’s kind if weird. There are multiple part numbers and I don’t understand the difference because the cost jumps around a lot. The engine without the anti-theft sticker (whatever that is) is about $1200 less than the engine with one. And then there is another auto engine part number with an even higher price listed as a short engine, but no explanation. So I’m not sure if it’s new rather than rebuilt, though it’s hard to believe new automatic engines from 2008 are still around. I have no idea. :dunno:

There's this:
N3Y2-02-200R-V0 for ≈$3000
Which Mazda call "Hp AT RX8 Eng W Rdot Labl"
https://www.mazdafactorypart.com/oem...l-n3y202200rv0

But I have no idea what "Rdot labl" means in tangible terms.

There's also N3Y2-02-200R-00 and N3Y2-02-200 which are both ≈$4000
https://www.gossettparts.com/oem-par...t-n3y202200r00
https://www.gossettparts.com/oem-par...t-n3y202200r00