nogoer

Bought my car privately and had i even known to do a compression test back then i doubt it would have been a convenient thing to organize. Not an excuse though and i did go into the car knowing an engine replacement could be a future possibility so no hard feelings on my end.

Results....(2004 out of warranty)
Rotor 1 - 6.7, 7.0, 7.8 @225 rpm
Rotor 2 - 5.3, 5.5, 5.6 @225 rpm

Obviously rotor 2 is shot or close to it in spite of the car running great and seemingly having decent enough power. They tested each rotor 3 times to make sure the results were valid. Service manager suggested that sometimes de-carbing helps to bring compression back up, but that he has a few times seen it have negative effects.

This test was mostly just for a state of the union so i could make an informed decision about replacing the motor or trading the car in. Since this is now my baseline i dont have any way of knowing or guessing at the remaining lifetime of the engine or if the low rotor 2 has been like this or is just now getting this low.

girth

iTrader: (1)

Sorry about your situation, and though you'll probably get flamed anyway for buying an '04 without a compression test, it looks like you did plenty of research.

Whether you decide to pass the buck or run it till it needs a new motor, at least you know. Good luck.

9krpmrx8

iTrader: (46)

Yeah that engine is done despite the slightly low cranking RPM. The lack of power is a tricky thing, my first engine that died was that way when I was bone stock, it felt fine but then all of the sudden started stalling and then the dealer confirmed it was low compression. When I got the new engine it felt like a new car. The power loss was so gradual that I just didn't notice it since at the time I was doing all highway miles.

nogoer

Researched yes, researched deeply, not so much. The past few months ive been debating trading it in anyway for something more mod friendly and with more stock power. I didnt think i would get the mod bug or realize that mazda overstated the HP numbers i was seeing when i was looking into the car. Once i did the basic mods within a week of ownership i discovered most did nothing for power and the regret starting creeping in. Dont get me wrong though i throughly enjoy this car and the debate is heated because its not always about HP!

I don't notice any lack of power, although i dont have any idea of what its actually supposed to be. I have had the car just over a year and only put about 3k miles on it in that time, but theres no noticeable difference in power now then from when i first got the car. I did start to see low idle issues a few weeks ago but then i failed emissions for the SSV stuck, spent a weekend tearing it out and cleaning it and then proceeded to realize the idle was now back to normal. The car runs clean, quiet, and smooth with no bouncing rpm needle, no major vibrations or other issues to note.

What it comes down to right now is i DIY almost everything with my cars not just to save money but because i enjoy tinkering with cars. An engine replacement while well within my capability is not within my actual ability because i dont have a garage or things like a hoist/lift. So now im going back and forth between spending the extra for labor or just taking more of a loss on trade and putting that 4-5k into something else. Theres no guarantee a new engine will last or there wont be added costs during install and spending 50%+ of the value of the car to replace the engine doesnt seem like an efficient use of my funds.

jamesf

iTrader: (1)

you could always just drive it into the ground to get your moneys-worth and then when it comes time use that $$ you would have spent on mods you put it into something else.

9krpmrx8

iTrader: (46)

Yeah if you only put 3,000 miles on it then the chances are that the power was down when your purchased it. Whether it's worth fixing or not is dependent on many factors. But if you can't do it yourself properly then it's probably not worth it financially.

nogoer

I agree and it most likely means i have some time left before i really have to worry about driveability issues. I "can" fix it properly myself, but a dirt driveway just isnt the place to rip apart an engine. If i can find a reputable shop within driving distance then it would affect my decision, but right now i dont think the cost of the dealer swap or the risk of an unknown indy shop doing it are worth it. Im going to keep my eye out though, i dont mind dropping the 4k as long as i know im not getting screwed as soon as i drive away or dealing with ineptitude during the process.

poacherinthezoo

From your posts it sounds to me like you would rather off-load this car and start fresh than roll the dice on a new engine. I can 100% sympathize with you on that. It may be worth it to start looking around and test driving some potential replacements (it's free even if you do decide to keep the 8). You never know, you might find something you really like.


[While it may be down in power, a decent miata can be had for not all that much money, and that car is super-mega mod-friendly, while retaining many of the RX8's lovely handling attribute. With only 3,000 miles put on the RX8 in 1 year I'm assuming it's not your primary car].


Sorry to hear about your situation, and I hope you are able to come to a solution that you are happy with. Best of luck to ya.

nogoer

Yeah i think this is the case. I know forums tend to highlight problems more than solutions, but the reman QA issues do exist and even at a 1% chance of a reman failure it is a gamble i dont think i want to take. Having to replace the engine once is one thing, having to do it again shortly after the first time and dealing with the added cost and hassles is a completely different story.

acroy

at the risk of starting a war -
maybe try the Seafoam or water injection as on other treads on the board, run it for a while, then re-test?

9krpmrx8

iTrader: (46)

Yeah sure seafoam will magically repair the physical damage done to your engine already,

TeamRX8

iTrader: (25)

it's a lot higher than 1% IMO

monchie

I may have to try seafoam or de-carb, and maybe it might improve the compression, even though if its just a little bit or something...

j9fd3s

i was talking to one of the techs at the dealership, and they had a car come in with low compression, and the service writer (who was new) sold the decarb process.

the decarb took that engine from 7.8's to 8.0, which is barely failing to just passing.

car came back about a month later for the same low power complaint, so the tech was thinking engine.

if the service writer was not new, they would have decarbed it, tested it and then done the engine right then, maybe