engine is failing if not starting while hot if plugs/coils are good. Check those, and examine if your losing power around 6k and beyond. Also theres the new hot plugs which I failed to purchase as well

 

I believe my engine was flooded, took out the plugs, dc eccentric shaft and cranked it and some fuel came out from the holes, put everything back together, still doesn't start... now checking the PCM??

 

I have this problem with my RX-8.
The way I understand it the thermostat that instructs the management system that the car is warm before turning the engine over is prone to fail.
Therefore it sets the fuel/air mix for a cold start in every situation. Hence our cars start on the money every time when cold, yet never when they have been warmed up.
I have been told that this fault will not show up on mazda's own diagnostic.

 

Who told you that crap.....the ECT sensor failure is easily diagnosed.....and will show up on the iDS scan.

The PCM looks at the ECT temp sensor data and the IAT temp sensor data on starting and will even throw a code if that is too far from the expected range

If you are having warm start problems...get a compression test to rule that out...and then go from there. It would be a good thing to know anyway....

 

i never have acold or warm start problem.

 

A mechanic who specialises in diagnostics with 30 years experience told me that. He also stated that the engine coolant temperature sensors rarely show up or give a fault code read on the diagnostic. Especially if the engine is tested from cold. This stands to reason as I only ever have an issue if the engine has been worked up to a high temperature over a sustained period of time.
As for the possibility of compression issues, I am very doubtful, my engine is pulling harder and faster than it ever has before at 24,000 miles.
Apparently the crank shaft sensors are also prone to failure.

 

How can you say that your engine is ok without the proper diagnostic? It looks like you rely on what a tool says for everything else so this is kind of a nonsense.
I'm sure that your engine is ok at 24000miles though.
I only had 1 ESPS failure on a car that hit a pole with the nose so i don't think that those sensors are so prone to failure as you may think.

 

I have already had a full diagnostic done at Mazda prior to posting.

 

Posting in this thread as I'm having the exact same issue now.

Already had the new starter put in 2-3 years ago, and it was great until about two weeks ago.

Have had all recall work done on my 2004 MT, and last week replaced the plugs/wires to boot.

Brought it in for a compression test, it tested better than when I bought it (expected) and the numbers are great.

So my question is, where do I go from here? Car starts fine, with a slight hesitation over what it was two months ago for example, when it's cold. Cold starts are never a problem.

When the engine is hot/warm though, it struggles, often times taking 8-10 seconds to start, usually over two starting attempts.

So now I'm left with the starter, which is relatively new, the coilpacks, which were replaced with the starter so are pretty new, maybe the solenoid for the starter or fuel injectors? Any advice would be appreciated. I've actually had great luck with this car mechanically (go figure) but this one has be stumped.

 

Battery ?

worst case is your engine is going down.

Compression test doesn't mean 100%, do a vacuum test too.

 

The battery was also replaced 2 years ago with the starter and the coilpacks, so I don't think that's failing.

What's involved in a vacuum test?

I also tested whether or not it might be the fuel pump, by turning the key to the start position, holding it for 5 seconds, return to off, wait two seconds, then rinse/repeat 9 more times. Didn't make a difference.

The car has never flooded before, and if I hold the pedal down (no fuel) it will never start. If I give it some gas (pedal halfway down) it starts, although it seems like it works best to get it to start turning over, then push the pedal down on the 5th or 6th crank.

 

do a video to show us the cranking speed . I recently had issues with hot starts and it turned out to be a worn out starter . Cranking speed was the key ...

 

When your engine is hot try running it when stationary for at least 30 seconds and up to a minute before turning it off. This should help until you identify the issue.
I still haven't got round to a fitting a new ECT sensor yet (not that anyone seems to agree this could be a problem on here) so I can't confirm if the guy is indeed a 'tool' or not at this time.
Let me know how you get on with this one and I'll keep you posted on any progress I make.

 

I'm bringing this thread back from the dead...

I'm new to the RX8club (obviously)... bought an '04 yesterday w/ a newly rebuilt motor w/ all Atkins seals... I wasn't informed that it was having this exact same issue; both times (test drive and pickup) the car started right up and then today I started to notice this exact same problem after having driven it around for 15-20min, shut down, and then tried to restart... on two occasions I tried to start up and it took more than one 8-10sec crank w/ no turn over. I did notice that the longer it had been sitting the shorter it took to turn over and that's when I realized that it was a hot-start issue and not a flooding issue (that, and when I push the gas pedal in to shut off the fuel flow it doesn't even crank)... I'm going to start by checking if the starter is the original or one of the new-er ones, then I'll check the ECT sensor... I bought it FROM a local IMPORT PERFORMANCE MOD shop and I've seen the pictures of the engine rebuild they just did on it - and that's the most frustrating part! It has 64k mi on the body/frame/etc...

Since the last post (9mos ago!), has anyone had any luck w/ their hot-start problems? Any results from dealer visits?

 

@Short304

Don't quote me on this but I am pretty sure the dealer will "upgrade" you to the newer starter for free if you do actually have an original starter.

 

Here is how I got mine starting right....

http://www.youtube.com/watch?v=oODr599cQv4

Keep in mind that normally really bad hot start issues are associated with low compression / excessive carbon build-up / ignition. I wonder why that shop rebuilt it instead of Mazda....

-Shawn

 

Thats a Negative. Trust me...

 

I jacked it up tonight and checked the starter model - using one of my wife's little make-up mirrors cuz I couldn't find my little telescopic mirror, AND cuz I couldn't get one of the 14mm Starter bolts to come loose (I'm going to wait till the tranny-case cools down and try again) (I wish my 1/2" drive set wasn't back home in CO right now!) - it's an N3H1... looks like this'll be my starting point... no pun intended

Thanks for the video Furry...

 

Thanks again... I miss-spoke; he said the engine was rebuilt from Mazda... he/his shop upgraded to the Atkins Apex seals, and then did the coils, plugs, wires, and fluids (and some other non-engine related stuff)...

I just rewatched the video and it's great... what's the model # on the Mazda 2kW starter? Looks like that might solve my hot-start problem - hopefully...

 

I got this one. http://www.buyourmazdaparts.com/inde...t_detail&p=454

 

WOW - great work on the video man !

 

Perfect! Thanks brother! Holding my breath that this will help...

 

What's the mileage on the car? If the rebuild is ok it may be a fuel pump issue

 

A quick and easy thing to try is cleaning your MAF sensor, a can of MAF cleaner costs like $3, it takes 5 minutes, and it seemed to cure all of my warm start issues (No more having to have 4 attempts at starting at the gas pump here! )

 

I was considering that too, but ruled it out do to the fact that I'm only having the issue when the car's hot... like a dummy, I stopped to grab some beer on the way home from work tonight and it took about 15min (18 tries) to get it to turn over... each time it got closer and closer until it finally turned over. The body has 64.5k miles on it.

This is definately on my list of less-expensive things to try... thanks for the advice.

I ended up ordering a 2kW Beck Arnley Starter from Autopartsdeal.com... paid an arm and a leg for overnight shipping but still probably won't get it till Mon... I'm really hoping this helps, but I'll definately take your guys' advice. Thanks again