Hey guys, so I recently bought an RX8 after much research(Last car being a g7 Celica) and am now having a few troubles. First and most prominent is starting the car. it takes anywhere from 3-7 seconds starting cold, and when warm it takes much longer, not to mention it doesn't always start. Second thing is gas mileage; I didn't buy a car for the mileage, but I'm getting around 8-10 MPG. The coils and plugs were replaced at 60k and had the MSP-16 software upgrade done also has a 08's battery. This weekend I will check to see if I have the upgraded starter(No mention of it on the service records) and I'm also getting the recalled clutch pedal installed on monday.

So obviously for the starting issue I assumed starter motor or possibly low compression, but accounting for the Low mileage I'm not sure what to think(Doubt it's cat because it just passed smog) any ideas?

I'll be doing a Mazda engine cleaner this weekend because I have some handy but other than that I'm not sure what to do.

Cold Start
Warm Start

2004 Rx8
Miles: 73k
Tranny: Manual 6sp

 

has it had a compression test done?

 

No but I'll get one this coming monday.
Just a little frustrated paying $100 for a comp test right after buying it.

 

sounds like a new engine is needed.

 

if its the engine, you dont need to pay for it.

 

how dirty are your MAF and air filter?

 

Can't speak for the MAF but the air filter is clean.
How long does it take for a new engine installation?

and if the new engine blows out, I assume that one I'm paying for? or does the new engine come with another warranty?

 

clean your maf. it takes 10 min.

New engine could take anywhere from 2 days to a week (depending on who, and how knowledgeable ). If you're under 100k miles, replacement of the engine is covered under warranty.
Do a search for replacing engine...

edit: no, engine doesn't come with new warranty. However, the 'car' warranty will always be 100k miles, even if you go through more than 1 engine!)

 

Rx8Solider, thanks. Based on the slow cold start we at least know that it needs a new starter right? Or can slow cold starts be due to low compression as well; I havn't found much info at all on slow cold starts despite my extensive searching.

 

the slow warm start is a pretty big indicator of low compression

 

What temps are you seeing when you start the car? Cold temps usually have an effect on the start.
I don't think you have loss of compression. Your idle at warm start seems on.
So, to answer your question: Yes, cold start issues could be caused by bad starter. Find out which you have, and replace if needed.
However, don't rule out cleaning the MAF sensor. I'd do that before doing a decarb of the engine...

edit: just watched the warm start again. Yeah, that's slow! May be compression... maybe not

 

has your car ever stalled at red light/stop sign ?

but it does look like u need an engine, because seriously even my last engine start faster than yours.

 

low compression engine can idle fine most of the time.

 

Never stalled randomly. Always idles beautifully, stays right between 900 and 1k rpms. rev's nicely, power shoots up at 5k rpms or so. The only symptoms really just seem to be confined to the starting and gas mileage.

and solider, I live in cali, middle of january and it was 55 today


But if I am able to get the engine replaced for free I'll be happy, I was considering TRYING to blow the engine before it reached 100k but then got worried about missing a service record or something...

 

if you have low compression you will have hard starts while warm and low gas mileage, all signs point to yes on this one.

as far as idling, you shouldn't have a big issue as long as seals are intact and at least giving some sort of compression.

be aware that it will most likely get worse untill you lose a face or two. go get your engine replaced after a compression check to confirm the issue

 

Yikes, taking it in monday. I might just leave it there!
Is there any way to know how long I have till it goes?

EDIT: And what is power loss like when you're down on compression?

 

not really any way of knowing, just means the motor is on its way out. could be months or weeks, even a year or two. But one thing that definitely doesn't happen is it get better.

im not sure how to categorize power loss, other than the words power loss. less power

 

Lol I meant as far as HP losses, with lower compression how much hp is lost, or is there no significant power loss with lower compression?

 

At least try all the easy stuff , Clean the MAF , check the plugs , check the coils again , see what starter you have , do both computer resets , unbolt the cat and inspect it . put a midpipe instead of cat and see if that helps . When I got my car i was trippin out on how it acted because I was not familiar with the renisis or rotary's for that matter .

Mine :
Idled rough
Started hard when warm (though not as bad as yours)

I replaced coils , plugs , air filter , cleaned the MAF , did both computer resets , changed oil , tranny fluid , put a full agency exhaust with cat delete (loud), premix in gas . After I did this my car runs sooooo smooth now , Sometimes I have to look at the tach to see if its even running .

The single handed biggest difference was taking out the cat and cleaning the MAF . Ive never got so much results in 15 mins then I did from taking the MAF out and spraying it down with brake clean . I just searched the **** out of this site and found almost everything I needed to know even though I jumped the gun on a few and started a thread .

 

bite the bullet and get a compression test, it will tell you 100% if it is a compression issue. dont spend a bunch of money trying to chase a smaller problem.

low compression can lose anything from a few HP right up until all of it, depending on your compression and seals

 

your butt dyno will not be able to tell the "slowly but surely" dying engine.

 

Not getting technical but don't all engines start dying as soon as they are started up for the first time?

 

Lol hotdoghogie.. yeah i guess they do. As does everything else..

and ok, Im taking it in monday to do the clutch and ill get a compression test done.

Tomorrow I have a bunch of spare time so I'll check everything out, clean MAF maybe do a de-carb, painting my calipers like a good little ricer

I'll unbolt the cat tomorrow and see if that does anything. let you guys know in 12 hours!

 

...... you are in denial

 

I have a warranty...

If it truly is free I'd love a brand new engine.