Advice please - serviced 05 RX8 and now wont start
 

Hi All,

05 2.6L 6 speed manual 92K miles, Uprated starter motor and cooling grill.
She is fine with Hot and cold starts due to uprated starter motor.

I am new to posting threads, but not new to this car / engine / engineering

Ill give you the readers digest version.....
Started up this morning fine, (i always follow start up procedure, clutch in, wait 8 seconds, crank, once fired hold at 3500 rpm for 5 seconds, clutch out)

Drove about 50m, including being stood at lights for about a minuet and I had a lumpy chucky sound from engine, engine light came on.

Diaganosed as fault p0302 - miss for on cylinder 2 - or second rotor in this case
under cranking at this stage you can hear a small pop as if one rotar firing, the other not.

Replaced, plugs and Leads just now.

cranked and the 'pop' had gone but now she seems to sound as if EITHER there is no spark at all, or flooded.

I am going to try the de flood method shortly when my freind is home from work (jump leads for battery boost, fuel pump relay and fuse, cranking, and reinstal)

but I want to know if it could be anything else that I am missing. It may well be obvious in the face but if im over looking something that has eluded me, always good to have some elses input.

Only other info I casn give is recently she seemed to need slightly higher revs to pull of the line, which again would point to loosing ignition.

Any words of advice would be very much appreciated.

Cheers guys

Moving to troubleshooting, but if the engine sounds REALLY lumpy, then you probably have damaged/missing/broken seals on one of the rotors. If that is true, it's time for a replacement engine.

I'm also guessing that it is flooded and unfortunately de-flooding is not easy at all. Your ignition coils are probably deceased and causing this headache. Did you say you rev it to 3500 every time you start it?

Paul.

i would pull start it and if you get it running check the ignition on all 4 plugs with a timing light.

if the coils and wires are original you may consider replacing them as well, with them having over 90k on them they probably are done or about to be. but it may be best to diagnose the engine first, as it is probably flooded by now and you need to figure out if the engine is good or not.

You forgot to replace the ignition coils when you changed the spark plugs and spark plug wires. Try replacing those, and hope your engine hasn't been badly worn out from the failing ignition system for so long.

Also, how long and how many miles have you owned the car?

BC.

Just done the de flood and it fired reluctantly.

Engine light gone out and idles at about 800 rpm ish - as it always has.

I have no throttle responce though. I can tease it to rev up.

It will rev all the way up but engine doesnt sound right.

I want to say a lumpy sound or somthing.

Engine light stays off untill i tease throttle up then flashes??

Loads of smoke has come out - as expected.

Has the cat gone and there for pressure of system?

I am so buggared if I cant get this fixed.

Thanks people

Ignition coils are a wear item, how old are yours?
Next step: compression test to see if the engine is still sound.

It is due for a service round about now and I have owned the casr for about 4K miles. May be a bit more.

The sound is more a kin to a deep induction noise. Tons of smoke as mentioned previously.

Does rev all they way up but engine light is blinking when I rev up.

Please any help / advice is much appreciated.

Reading other threads there is other with this rough idle and low power thing.

Pointing more to the coils.

Also If the air intake has been bothered and messing with fuel mixtures?
O2 sensor may be?

Still confused as origonal diagnostic code was for mis fire on cyclinder 2.

is the engine light flashing to tell me ECU is re establishing fuel air mixture?

Loki, how does one conduct pressure test? Is it to the garage?

Please read all posts above also

Thanks kindly

If the second rotary lost ignition, could the timing be off now and hence rough engine, smoke and low throttle responce?

If you read an "ignition coil replace diy", and can manage to take them out, look on the bottom side of all 4. If they are bad they will have big circular burn marks on the bottom. Mine did.

These cause misfires like no1's business. It'd be good for you to replace them regardless if they are old, but you need to get some1 to do a compression test on your engine. 8 years or 100k miles for warranty on it (and I think it's 8 years from when it was sold off the lot, some1 correct me if I'm wrong. I just know for some reason mine is an 05 but mazda calculated mine lasting till 2014 and mine was sold off the lot in 06). You can also contact Mazda and ask them how many engines have been in the car too if you give them your vin #.

Expect to pay up to about $200.00 for a test.


I dont think your ECU is whining about the fuel/air mixture. If you unplugged any hoses from the intake/throttle body, you will have a vacuum leak and you will get a CEL for mixture being too lean. Generally the flashing CEL is for a misfire though. Also, the ECU is very smart on this car, so unless you put some kind of weird-a** s*** in it, you wont be getting CELs for it recalculating anything (IE, you put in an aftermarket intake/exhaust).

Flash CEL simply means misfire, nothing else.
You'll need to bring it to rotary shop to perform the test, unless you have the tester for rotary engine.
Burn mark on coil doesn't mean anything, it's been discussed.
Coil would be the next in line to replace.

Hi,

Thanks for your responce, I have taken of coils from the rear rotor, and will be replacing in an hour or so.
Have not unpluggen anything from air intake system. There is a small black plastic case thing on the side of the intake pipe. Not sure what it does, had to take it off to get the plug wires off and coils.

daft question but always best to ask if unsure - coils are the squarish components that the plugs connect into, that are bolted to the top on the engine, each of which has a electrical contector on it?

Spoke to mazda garage local and said they change alot of coils, could be cat that has collapsed also. Going for the coils next thgouh.

So flashing engine light is misfire only???
It has been regularly serviced, it is due for a service round about now so is it possible a bad coil has come?

Hi,

So flashing engine light means misfire??. As I said previos diag code = p0302, miss fire on rear rotor.

I am doing the rear coils in an hour or so when my freind can bring me the bits.
Will compression be lost just from miss fire?

As in previous posts in this thread, it was fine and went into this low power rough idling out of the blue. Replacement of plugs and leads got rid of eingine light and it doesn come on untill i rev upwards of 4/5k+ then if flashes. doesnt cut oout just idles very roughly.

Again leading me to the coils??

Yes, ignition coils are the 4 pieces that are plugged into the other end of the spark plug wires (opposite the spark plugs of course). Yes, they are below the stock intake system but above the motor.

Shinka is right, flashing CEL means just mis-fire. Says that in the owners manual actually.

You won't know until you replace your coils whether they were the issue or not, but it very well could be a mix of problems. I feel like your Cat would be worth checking once you eliminate coils and compression as an issue. But from what I read clogged cats can cause a variety of problems including a poor idle.

Thanks man,

ill do the coils and then look at the cat. I will look at the cat before i try strating anything up.

I have to take yesterday, today and tommorow off of work. Got 3 days to try and fix other wise im going to be cycling to work for the next few months.
30 mile round trip wont be fun.

Any body any other ideas that I can consider if the coils are not the issue.

Thanks kindly for you understanding, I am an aerospace engineer and design and build jet engine blades and vanes. Rotary engine scares my far more than work! So I will ask the daft stupid question and make sur eim right.

Again appreciate the help.

Any body any other ideas that I can consider if the coils are not the issue.

Thanks kindly

done the 2 coils on the second (rear) rotar. I did notice on the back of them there was a cirular mark, about 10cent (5p in UK) big, not exactly burnt or anything but noticable.

Have not tried firing her up yet, want to make sure I have a good spark with a second battery hooked up, when my friend gets home from work shortly.

Any other clues may be?

Again thanks you guys all so much, really are a good bunch on here

I'm confused ... you have two threads now?

https://www.rx8club.com/trouble-shoo...oblems-242547/

Yeah timing problems,

I had alot of tabs opened up and hit new thread instead of trending this one - too much caffine!

Timing problem thread is most upto date but i know it not to be timing.
changed rear rotors coils (cant afford full set. as p0302 was issue [misfire on rotar 2] i hope this along with complete new plugs and lead helps)

Also Just done 20 break stomp and going to clean both MAF and ESS sensors after lunch.

Will put in a gallon of petrol on top of the 1/4 tank have already to make sure its not low fuel.
Then will hook up to second battery to make sure got a good spark and try and pray to god.

Failing that Ill move to the CAT and remove and gut that. I know if mis fire occurs cat will fail quickly but it missfired on rotor 2 50m from my house and i got it back carefully so 100m in total at low speeds and never got really hot.

Thanks for your comments :)

Slow down chief, you're all over the place. The answer is coils. The question is if there is other resulting damage.

Thanks Loki,

I have replaced rotor no.2 coils,but not fired it up yet.

Would there be massive damage from a 50m (if that) carefuly drive back to my house and starting it after plug and lead change as described previously

thanks

Do NOT drive it in this condition until ALL of your coils are changed.

could you please explain little further?

If I need to i can replace all coils at a push

thanks

cant get hold o the second two coils untill tommorow.

What is potential if I start it with the two rear coils replaced?

Thanks