gabeslezak

I have a 2004 rx8 MT with 43,000 miles on it. Takes about 1.5 seconds to start. Sounds like from other threads that's normal? But anyways after the car warms up and im at a stop light or in a parking lot just idling the rpms fluctuate after 25 seconds or so. Its like an engine misfire for a normal engine, runs at about 1k and will dip to like 900 and then back to 1k real quick. I can feel the car shake during the half second it does it. It never goes about 1k or lower than 800. It kinda vibrates the whole time it idles too (nothing real serious but you can see the stick shift vibrating) ive been reading forums for several days but nobody seems to have my problem. Seems like everyone elses is more severe. Ive seen youtube videos where the rpm doesn't move at all so there must be something wrong. I just bought it from a dealership less than a week ago and the dealership is an hour away so I dont wanna drive there and find out my small warranty doesnt cover it. It only seems to do it when the engine is warm and only when im completely stopped. The ac doesnt seem to play a role. I paid about $17,000 for this car after taxes and my outrageous 24% apr. Any help is appreciated. I have new plugs wire and coils in the mail but I have a feeling it wont fix it. Also just put lucus fuel system cleaner in but that was only 5 miles ago so it hasnt even gotten a chance to take effect. Thanks guys!

patriotjj

Your symtoms are exactly what my symtoms are, when I had a vacuum leak at the same time of my engine having low compression. You said you couldnt find another post like it, go to the "new member" tab, and my post about "vacuum leak--thoughts??", sounds like the same symtoms I was having. Starts were about 1.5-2 seconds. Car would vibrate at idle mainly only when hot. Took it to get a compression test, and the engine failed it horribly.

gabeslezak

I just read your whole thread. Crap low compression? That means you need a rebuild doesn't it? Or could a vacuum leak cause it? Sounds like we have the same problem except my car isn't showing any warning lights or check engine lights. Thanks for the quick response. Also where did you get your compression test done and how much did it cost

patriotjj

I am not near the smartest person on this forum. But from my experience, and from what I have read(hours and hours), your best bet is to stop throwing parts at it, and get a compression test ASAP, you may need to have the plugs and coils in, as some Mazda dealerships will try and say those should be updated before a compression test. Because I myself, 1k Miles before i got the compression test, threw coils/wires/and plugs in, and it merely coated the real problem for just a little bit. As for the warning or engine light, mine wasnt as well. Vacuum leaks could cause those symptoms, except for the longer starts i believe so if you want to do a quick check just to see if yu have any, do the "carb cleaner" trick. But you only want to get a proper rotary compression check from a dealership, 150-200$. But yes, a rebuild or Reman.

gabeslezak

Crap. Do you think the dealership I got my car from will cover it? I have a 3 month or 3,000 mile warranty with the car and if it fails the compression test you think the dealership will put a new engine in it or no because it hasnt completely failed yet?

patriotjj

Only thing i could tell you about that, is what exact warranty did they offer you? I have an 08, with the 8 year/100k miles that covers main engine parts(seals/gaskets etc), read and check your warranty, if it covers main parts, then yes, if your car fails the test, they will not make you pay for the test or engine. You can also read my "Failed Compression..BUT", thread.

RIWWP

iTrader: (2)

Failing a compression test means that the engine is failed. They are equal statements. It is one of the unique attributes of the rotary, in that while they "die" a bit faster than piston engines, they can run for long past being legally dead. Piston engines self destruct in short order, not rotaries (except a few possible cases that don't apply here).

If you are still within that 3 month 3,000 mile warranty, then yes, get that compression test ASAP, and if you fail, have the Mazda dealer contact the dealer you purchased the car from so the Mazda dealer can bill your dealer for the replacement. Don't try to convince your dealer on your own. Have the Mazda dealer contact them first. They have less wiggle room to try to keep from covering you. Given how much you paid and at what interest, i'd bet that they will try to get out of covering you.




You paid $17,000 for a 2004? How long ago? I paid $19,000 for a 2005 loaded GT with 8,600 miles back in 2007... 2004 MTs with good compression are worth ~$9,000 tops, $7,000ish is more fair. Low compression is more like $4,000, and no compression is under $2,000. I had to look up your IP to make sure that you weren't talking a foreign currency. Did they hold a gun to your head on this? It is pretty much robbery.

And people sell their 8s when the engine is dying, to hand off the repair cost to a dealer, warranty, or a new owner that doesn't know to do one. It's why we spend so much effort trying to get new owner's the info to get a compression test first.

gabeslezak

Yeah im paying over 4 grand in interest and it has the red and black leather interior, one owner, red, not a scratch nor dent on the car, the bottom of the car still has red paint from the factory, it was never driven in snow. Unfortunately it sounds like rx8's have a ton of engine problems. I think I paid 12k just for the car before tax. I purchased the car 5 days ago

Chrishoky

iTrader: (9)

Yea you got shafted. Thats way too much, even for a car that is spotless on the exterior. The engine is not as prone as to problems as people make it seem. Unfortunately it is common that people dump off their problem of a car onto someone else, which is what happened in this case.

RIWWP

iTrader: (2)

You got completely hosed on base price and interest. You may have fallen for the justifications the dealer gave you but.... no.


Get that compression test.

patriotjj

+1^^ what chrishoky and RIWWP said, thats ALOT of money for an 04 with that many miles on it too. I paid 7k for an 08 with a couple dings on the front hood and 68k Miles, still under warranty for another year.

gabeslezak

Yeah I know I paid a **** ton but I had zero credit so that's why my apr is so high and for some reason in ohio dealers are selling them for 12k and more but you can find them cheaper on craigslist. Thinking about buying an extended warranty from endurance just so I don't have to worry about the car

patriotjj

Hey, but it is an AMAZING car in my opinion, absolutely love it. Just take it as those are signs of low compression, and if it fails, youll have a better engine then you do(most likely), also are you having low rpm(smooth) power loss? As that was another little symptom I was having.

Chrishoky

iTrader: (9)

You can always try the lemon law in this case? You say you purchased the car only a few days ago and its already giving you this much trouble? I dont know the legality of these things but I would look into that for sure.

RIWWP

iTrader: (2)

Actually, it looks like you might be in luck for that...

Ohio's Lemon Law:
http://www.ohioattorneygeneral.gov/I...uto/Lemon-Laws
In this case, you can only get out of the car if they can't fix it... but they will be able to. It won't be on you.

gabeslezak

So even after the 3 month warranty is up I can still get the car fixed under the dealers expense with the lemon law? And it doesnt seem like it has much power loss. It redlines and all that. Sorry Im just at a complete loss right now. I absolutely love the car but this idle problem is just incredibly stressful for just buying the car. I don't have another car to drive while they do the compression test and stuff

gabeslezak

I just read that the lemon law doesnt apply to used cars

RIWWP

iTrader: (2)

New owner's have NO idea what a health RX-8 feels like compared to one that is near death. Time and time again new owners think that the car feels fantastic, find out the engine is dying, they get a replacement, and are completely blown away by the difference.

A dying RX-8 will only feel like a dying RX-8 if you really know what a healthy one feels like to begin with.

The compression test should only take 1-2 hours. Seriously, go get it done. You don't want another $5,000+ bill on top of the overpaying that you already did. Get the test now.

patriotjj

Oh trust me... My car literally only had 1.5-2 second starts and the idle was rough when hot, literally the only problems. I could get to redline QUICK, power seemed great and everything after the first 10mph(but the Rx8 is naturally not speedy fast off start), never in a million year would i think the engine has failed, it got Mid 5's and low 6's on all faces.. Yeah, my car went in on.. Monday for test(took 2 hours for call), and wont be getting it bAck until late next week.

And RIWWP, i cant wait to see what it feels like with the Reman. Never felt it.

RIWWP

iTrader: (2)

Whoops, you are right. I didn't read thoroughly. It does for some states, but not Ohio.

So yes, you only have that 3m 3k to get the issue fixed under warranty.

gabeslezak

I left my old car at the dealership. Might pick it up friday and then take my rx8 into the dealer after work monday. So if I didnt have warranty, has anyone ever heard of using that engine restorer **** in the silver bottle/can meant to restore compression? Wondering if anyone tried it on an rx8. Kinda hope I get my engine replaced so I dont have to worry about it for awhile

gabeslezak

I studied my rpms a little more closely today aftet I got to work and it was idling about 800rpm and still felt the misfire like cough but rpms barely changed (maybe like 20 or 30rpm more) it doesnt feel like its going to stall at all it just kinda "coughs" once and awhile. I can try taking a video for you guys and hopefully we can figure out the problem and help other people with the same problem. Im assuming its a fuel problem or maybe its the oil being injected and not burning completely causing the cough. I know the manual recommends 5w-20 oil but does anybody know a better oil to put in? Can I put the lucas oil additive in or will it just cause more problems? Ive heard of people using synthetic In thier rx8 and claim its better for the engine than 5-20 but I also see people saying its absolutely retarded to put synthetic in. Thanks for all the help guys. Also the engine temperature is fine and oil ppressure is a little above half.

RIWWP

iTrader: (2)

OIL IS NOT THE PROBLEM.



Seriously. There are two possible results from oil:

1) You have oil, the engine isn't seized.

2) You don't have oil, the engine is seized.

The weight, type, or brand of oil you have in it has NOTHING to do with combustion control or idle stability. The only thing it impacts is e-shaft bearing wear, which will take >100,000 miles to ever become a problem if you consistently use a thin oil. Otherwise, the only time oil can be the problem is if your engine is seized from running out of it.



Idle stability problems could be one or more of:
- Compression loss
- Coil failure
- Plug wire failure
- Plug failure
- front O2 sensor failure
- MAF dirty
- ESS dirty/misaligned
- electrical grounding problem
- clogged cat
- Vacuum leak
- clogged air filter
- carbon caked engine
- failed coolant seal
- failed oil control ring



You still need that compression test.


And the coolant temp needle will not tell you if you are overheating. It doesn't move until 235F, and you can have a coolant seal failure as low as 220F.

And the oil pressure needle does literally nothing. Full left = engine off, middle-ish means engine on, full right is only possible under some diagnostics. There is no oil pressure sensor in the engine.

gwilliams6

Please take all our good advice and immediately just go and get that rotary compression test done. STOP beating around the bush with talk of other temp solutions.

After that come back to us with the numbers and we can tell you if the engine is failing and then you may need to use that warranty to get a reman engine replacement.

There really is NO other choice in what to do first.

patriotjj

PLEASE... Do not be blinded and be in doubt that your engine has possible failed or failing. I was in your shoes man, tried replacing a bunch of stuff, cleaned everything also, you might think your idle isnt bad, mine wasnt either, the needle would jus tick 20-100 range for not even half a second, but you could def tell the idle was a bit off. Compression test before ANYTHING. Seriously