Mr Morlock wrote:If you look at the Mazda workshop manual is goes thru a trouble solving listing- whether you have the equipment to check or knowledge is another thing. Join the club of not being the full bottle on all things for diagnostics on modern engines. If its running rich I don't think it will have anything to do with cam angle sensors but take that as something not to be relied on. Replacing plugs will make no difference i.e. if they are black then you are looking for root cause - the black plug is the result. Mechanics can check the diagnostics on the car. Its good if you can do swaps of components but that is not always possible esp if you do not have mates with this model. It may also be related to the coil(s) but if it cannot be replicated in a workshop its tricky.
Thanks! I didn't expect plugs to change anything, just mentioning it. It's the only thing I changed since I bought it (A little over a week ago)
I know nothing about modern engine diagnostics, but open to learning. I was hoping that I'd get some flashes out of the LED as per various internet how-to's but wasn't particularly optimistic about it.
I was hoping that it would actually start happening consistently as I know that as soon as I book it into a mechanic it will behave. I've had this with any intermittent issue previously.
The cam angle sensor is only on my list because it seems people have mixed issues with it.. so worth just trying.
I had a hunch about o2 sensors, but figured the engine diagnostic would have picked that one up.
(Only thought o2 because of mix. I also thought air-flow sensor, but feel I've ruled that out.)
I was hoping to just make sure it's not the coils as it's something I can try easily and replace myself. I don't know anybody with an MX-5 in the area (let alone the correct model), hence this post to see if anybody would be keen on helping me out with a diagnostic swap. Doesn't hurt to ask, right?
I started reading up on bench testing coils, but it would be easier to plug another in. I'll try to find the workshop manual and look over the steps you mentioned.
speed freak wrote:So its an intermittent issue or happens quit regularly?
It happens quite often but not consistently. It was fine when cold this morning, and when I drive it home at lunch, then rough when I hopped back in. It feels like it's happening a bit less than half of the time.
speed freak wrote:Im near Helensvale so I could probably meet you Thursday arvo/night if you wanted to try the cam angle sensor since mine is fairly new.
I could make it to Helensvale, I'll touch base with you on the day and make sure it's still fine. I really appreciate it.
speed freak wrote:Yours could be the EGI relay on its way out too if its running rich. Mine smells very rich on a cold start, do you get poor fuel economy?
Certainly has some poor fuel economy. I think I got ~300km to my last tank with it mainly being drove when good. I swear I was watching the needle drop when driving rough from Burleigh to Broadbeach on Saturday morning.
speed freak wrote:When it plays up does it idle rough and drive rough or does it clear up with some rpm on board?
When it plays up, it idles rough and revs take a LOT of effort. It's hard to bring up to 60 and doesn't want to play, particularly bad at the lower end though (around 2k rpm) it will rev up, but havent taken it past ~3500rpm as it really doesn't feel like it wants to.
It has only made popping sounds once and usually just feels like it's struggling.