Hot starting issues Rx-8 2003
 

Hi all,

I just purchased a 2003 RX-8 4 weeks ago and its had starting problems since I got it. I've taken it back to the dealer twice now but it still hasn't been resolved :(

When I first got the car it had starting issues from day one, the dealer said its because its been sitting for a long time so I thought it should clear up within a week but it kept getting worse. I took it to Mazda and got a service done but it was still having issues. Mazda gave me a list of stuff I need to replace on it including the air filter, spark plugs and the recommended I change the battery to the Mazda one.

I took it back to the dealer who replaced the spark plugs. This has fixed the cold starting problem, it starts every time from cold after 2-3 seconds now. The new problem I have is when its hot it takes 6-8 seconds to start (if it even starts), if it hasn't started by then I stop cranking, wait a few mins then try again.

I took it back to the dealer about the hot starting issue and they had it for 2 days, they couldn't get the car to fault while they had it there. They took it to Mazda and got a compression test done and Mazda said it checked out fine. I asked them about the battery, they said they put a new battery in it when they got it, they have tested the battery and said it has the right cranking amps etc but it isant the Mazda recommended one.

I've been reading through this forum for days now and it seems people who has been having this issue put it down to coils, plugs, bad compression. Since the only thing I haven't replaced is the coils, air filter and battery so I am wondering if I should do these? I thought I should ask here first since these are quite expensive to replace.

Can anyone offer me any advice on what to do next? I hardly know anything about cars so its been quite stressful for me.

Kind Regards
Chris Grisdale

I don't want to beat a dead horse, but it seems as though you should have done a lot more research before you bought the car...

First, test your coils to see if they are working or not. Search the Do It Yourself sub-forum.
What model of starter do you have?
How old is your battery?

Also, where are you from? How many miles on your car? Is it auto/manual?

Sweet I try find out how to test the coils.

Mazda said I have the old started motor, they said there is a new version but mine didnt appear to have any issues.

Its a brand new battery but its not the genuine Mazda replacement one. The dealer took it back to the battery place that fitted it who tested it again and said it tested ok.

Its a 2003 Type S 6 speed Manual. Im from New Zealand and it was a fresh import from Japan, its done 75,000 KM's.

Chris

Battery is just battery, as long as u got the right spec, enough juice to start ur car, that's fine.
U might wanna invest in the updated starter, as it has more juice to start up faster.
Although nothing wrong with current starter, but i would recommend to get an updated starter.

Hi Shinka,

Do you know what the right battery spec is? Is there a way I can tell from the model of battery that is installed?

I've asked the dealer to get me a price from Mazda on upgrading the starter motor so will see what they come back with.

Hot Starts really are not that uncommon, at all. None the less, it seems you have done a wee bit of work which is good. What I would like to know - What were the results of the compression tests? Where is the sheet/what are the numbers?

Honestly even if your coils ohm out ok they could still be faulty. My advice would be to get the upgraded starter, and replace your coil packs eventually.

Don't worry about the battery being a Mazda one, a battery is a battery if it has the correct cranking amperage you should be fine. Having a mazda sticker on it doesn't make it king of the hill.

HI CHRIS!

My 03` rx-8 (90 000km) is EXACTLY doing the same, no trouble with cold start-ups. I however, crank timelessly for hot start-ups. its a embarrassing at the feul stations... no problems with my coils/sparkplugs.. to afraid to do a compression test...

Hi All,

I ended up taking it to a Rotary specialist who found a problem with low compression. The starting got so bad it had to be towed to the specialists.

The dealer is paying to rebuild the engine and upgrade the starter motor

Chris

Finally got my car back after a 3 month wait. It lasted 2 days before the fan belts exploded. Took it to a different garadge who said the pullys were all bent so he fixed them up and put new belts on.

Its now starting fine, it had a rebuild and a new starter motor installed. But it still has idle issues. The whole engine and air intake shake around when its idleing (you can feel it in the steering wheel and seat), I looked at my friends RX8 today and his doesnt shake around at all. I got a OBD reader and there were no errors, it idles around 800-860 RPM. If I push the gas and take it to 1000RPM the shaking goes away, its also worse when I turn the aircon on.

I've tried resetting the ECU again (20 pedal pumps and the odometer button) and cleaning the MAF but no luck. I've basically done everything except the coils, do you think they could be causing this issue or can anyone give me any other ideas? Im thinking about just taking the car dealer to court and getting my money back ive driven this car for about 3 weeks out of the 5 months i've owned it because its always in for repair.

Chris

Engine mounts, did you check em?

starter
 

i dont get it, ive seen so many rx-8s with low compression & people say a faster starter will fix it. well, i can see where turning the low compression engine over faster will catch & start. but this does nothing for worn out apex seals, is this not just a band aid to get a few more miles out of the engine? such as to hold u off until the warrenty runs out?

Im not sure where they are or how to check them? (The engine was rebuilt + a new starter)

Don't make the same mistake I did and get a compression check before you start spending money on replacing parts.
You said the dealer already performed a compression test, did they show you the numbers?

It failed a compression test so its been away for 3 months getting rebuilt, I just got it back and its got a rough idle so trying to figure out whats wrong still :(

Hi Shadycrew, I have an 05' base 6 speed with 36700 on it. My car has trouble starting when hot. Have new coils, plugs, air filter, MAF is clean, oil just changed, New battery, trans fluid flush and fill, and coolant flush and fill. Also, did compression test, all good. Does my 05' have the updated starter? If not, would updating this part help with the hot starting issue? Thanks much!

If the compression is fine for certain, then it is likely that the starter might be the issue since you have already replaced all the other parts that can be responsible for this issue.
Also, check around locally for shops that especialize on rebuilding starters and alternators. They can build you a high performance starter using your OEM core at a fraction of the price than if you bought it new. I only paid $120 for mine.

Thanks ShadyCrew! I will check around for a high performance starter. I think I know of a place. I did forget to mention that it is Winter where I am at. So with the car being up to temp and the outside temp of 25 to 35 degrees, could this be a reason for it not starting when its up to temp? Just wondering. I searched for a post of this, but didn't find one. Thanks!

mate..... if u have the orginal starter motor from build then thats the culpret without a doubt, if its starting fine from cold and just when it hot theres that whole...sitting in a petrol station trying to fire it up, looking like a fool situation then change that first. i had the same issue with mine when i got it, changed that - sorted!!

please dont listen to Mazda on this one, they will have u change everything & then turn round a say....err....i dono...!!

the original starter on the 03 was weak mate, fuck it off n get the later one, i got mine reconned from ebay...around £50 or somethin

hope thbis helps :)

I would double check the spark plug wires to make sure they weren't misrouted after the rebuild. You never know when its something as simple as that screwing things up.

Also, who rebuilt the motor?

BC.

If you follow the shop manual, rebuilding a renesis is actually pretty easy, assume u dont call for better clearance and u think stock seals size are all good enough

Assume nothing is wrong and the rebuild was done properly, the starter is not ur main concern. Replace the engine mounts first, then u replace the starter for 2007+ version. It should be 2.0 kw, but i seen some thats rated 1.7 and 1.8 it start fine.

Thanks everyone! I will definitely try the new starter! Just had the "Neutral switch" replaced. That seems like a common part that is replaced. My Reverse switch is still good so far.

So far since owning this car as of September of 2011....I've had plugs, wires, ignition coil, battery replaced, coolant flushed, transmission seal replaced and flushed, changed cabin air filters and air filter, had it de-carbed (Yep, flooded it once), got a new original gas cap (CEL kept coming on), couple of oil changes, and now neutral switch...Maybe a starter here soon.
I can't complain at all! Everything I've had replaced or that I've replaced so far seems like normal maintenance for the RX-8. :)

Any other parts that I should be checking or replacing?

So its been 7 months since I got this car and its still not fixed. I've now had the following done:

Full Engine Rebuilt
Spark Plugs Changed
Coils Changed
Wires Changed
New Starter motor
Full service (Oil, filters etc)
New Engine mounts
Reset the ECU

It seems to start alot better now (2-3 seconds crank time), has more power but it still idles rough. Once its warmed up, if I go for a drive its fine until I stop, the revs drop to 1000 then 1 second later drop to 800, at this point the whole car shakes alot then it evens out, it will then sit on 800 revs and the vibrations will come and go in pulses. Is this normal for the RX8 because I find it really annoying to be shaken around every time I stop at the traffic lights. I can feel the vibrations all over the car or if I lift the hood I can see the engine shake at this point.

I was thinking about getting the ECU remapped and cranking the idle up to 1000 RPM, either that or just selling the damn car. Anyone got any ideas?