Mazdagirl23

I am pretty new here. I have been reading a lot of posts, but haven't commented or started any threads of my own until now. I just got my 2005 RX-8 in July (traded a kid straight across for my bad tranny BMW, hoping I got the better end of the deal. Now Im not so sure). When I got the car, the kid I got it from told me the starter was going out. My car was not included in the few 05's with the recalled starter that Mazda replaced. I don't know any of the history on the car whatsoever. I never noticed long, cold starts until I watched everyone's videos with their upgraded starters and 1 second starts. My cold start is 3 or 4 seconds maybe, but it starts on the first try every time. On hot starts, sometimes it can take up to 8-10 seconds to start, sometimes it wont start at all. I have watched video after video on bad starters and have noticed the same thing in every one of them. The RPM gauge acts different than mine does, and I am hoping someone has an explanation (please bear with me, I don't know a whole lot about cars, and I am a girl ). It seems like everyone's RPM gauge stays on 0 when they are having a long start. My gauge goes up to maybe 500 RPMs. If my car is going to start, the gauge will stay there until the car starts. If it is not going to start, the gauge will drop back down. There are a couple other issues I have noticed with my car: my idle drops when I am in drive, but sitting at a stop light, and my car vibrates. The RPMs drop to about 800-850, then they come back up to around 900-950. The only other issue I can think of is the other day, I backed out of my driveway and as I was backing up, the car stopped suddenly, as if someone slammed on the brakes. It did it twice (and scared the crap out of me). What would cause this?!? Any advice is much appreciated! Thank you.

Mazdagirl23

My car has 83k miles on it.

The other day, my car sat for 10-15 minutes in 45 degree weather, and still wouldn't start. I have ordered an upgraded starter. It should be here in a few days.

Legot

iTrader: (1)

Your engine is toast. Sorry.

The vibration is likely it struggling to stay running and maybe a collapsed motor mount. It would have been cheaper to fix the bimmer. Rx8s are practically worthless.

Is this an automatic or manual? A new engine will be cheaper for a manual.

Legot

iTrader: (1)

Don't get me wrong, it's one of the most lovely vehicles in the world, it's just a pain to take care of sometimes.

If you decide to stick with it you'll see how rewarding driving a perfect one can be.

patriotjj

That doesnt sound to good.. As I was having the same problem. Long starts for COLD and HOT, was taking about 2-3 seconds to start, had vibrating at stop lights with the RPM jumpin around a bit. Turned out to be engine failure. After that starter, dont throw anymore parts on it until you can get a rotary compression test.

Mazdagirl23

It is an automatic. The more I read, the more I think it is low compression. I absolutely love the car. Realistically, what would it cost for me to rebuild my engine? Am I just looking at replacing all the seals?

200.mph

iTrader: (9)

when has your ignition been changed last? have you cleaned the sensors with normal maintence? do you have a cat? any check engine codes? it sounds like compression loss but you need to get it tested to be sure. 80k is also around the time for a fuel pump too

200.mph

iTrader: (9)

maybe a local member can help you out but a comp test sounds the right direction if your maintence is up to date

Legot

iTrader: (1)

It's most likely low compression, probably caused by other easily fixable problems. You will still need to have the engine rebuilt, but if you don't fix the smaller things first the new one will likely go within 20k miles.

I believe that the cost of a 4 port rebuild from a competent builder is in the $3k-$5k range. Not including the cost of removing and reinstalling the engine. In addition to that you would need to clean the SSV, MAF, possibly grounding (all of which are really cheap), as well as replace the ignition , plugs, and wires ($300-$500 for the best quality). The fuel pump should be replaced as maintenance at that millage, as 200 mentioned.

You will probably also need a new catalytic converter (or hollow your current one out for free). New they are ~$1700, and there are no useable alternatives to the OEM one aside from a midpipe. Midpipes/hollowed cats are great, but you won't pass most emissions tests.

Of course, it might just be other problems but chances of that are pretty slim. Get a compression test at a mazda dealer and let us know the results before buying more stuff.

Khurram

+1 with what 200 said

Get the compression test done, if that checks out then get the upgraded starter.

Mazdagirl23

The guy I got it from said he just changed plugs and wires. He said there were only 2. I have 2 new plugs and wires in my trunk that he gave me. This is my first rotary, so I believed him. Then I learned there are 4 so I don't know what the heck he was thinking. Or did for that matter. I don't know when anything was done as far as maintenance goes. I've only had it since July. I've put 3k miles on it, almost all highway. I had to replace the coolant overflow tank because the lip broke (where the cap screws on), and the radiator, the nipple broke while replacing the overflow tank. I cleaned my MAF last week. I do not have any check engine codes, but it does feel like it hesitates slightly when I hit the gas. I don't know anything about the cat. I've already ordered the upgraded starter, so I guess I'll just put it in and cross my fingers that one of these days we will have the money and I can convince my husband that I need a compression test.

200.mph

iTrader: (9)

comp tests are usually between $100-125 and before you start dumping money in it i would get that done first. because you dont know what the previous owner did with the ignition i would replace everything if the comp test comes back ok. check your cat, unbolt the front and inspect it with a flash light. all 12 of the ignition components can be had for under $300 and you can get lifetime warranty coils and wires from autozone

gwilliams6

I agree compression test FIRST If that is good, then other stuff like new coils, plugs and wires,cleaning sensors etc. Sorry it is an auto 4-port engine. they tend to fail sooner due to carbon buildup since they have lower rev limit and the auto doesn't do many wide -open-throttle shifts (WOT helps break down and burn up carbon buildup that can damage apex seals inside the engine)

Mazdagirl23

Since I had already ordered my starter, I went ahead and put it in a couple days ago. I have a comparison video of my starts cold, warm, and hot. They are better but my hot start is still twice as long as my cold start. However, it went down from around 7-8 seconds to 4 seconds or so. Here's the video if anyone is interested.

http://youtu.be/NxHQVbzxauk

Mazdagirl23

Did I read somewhere that there was something you could use to clean some of the carbon out of the engine? Maybe seafoam? Or something more specifically called decarb something or other? I try to rev it up but it is hard to get it to rev up higher than about 5k, which isn't enough is it? If it were up to me, I would for sure choose a manual over an auto.

Chrishoky

iTrader: (9)

Sorry but seafoam wont really help you if you have low compression

gwilliams6

seaform is a debated topic here, yes it is often done on rotary engines but most believe it has only a fractional effect on helping compression in a failing engine.

ftf1337

I am having the hot start issue as well but the car drives very well ... any updates MazdaGirl?

Khurram

ftf133..provide more details about your ride.

what year,
6spd / Auto
Miles
How old are the coils, plugs, wires
How old is your battery, starter and alternator
Do you have older starter or new upgraded starter.
Also, an estimated difference between cold and hot start would be helpfull