i am having an intermittent starting problem with my mazda mx5 icon.it only happens when the car has been warmed up and running for about 10 minutes.it starts 1st time every morning or if it has been sitting for 1 hour or more.the problem only happens once the car has been running and then parked for about 10 -20 minutes.the car will turn over but wont start or on the odd occasion it will start but appears not to firing on all cylinders but this normally clears after a couple of minutes.I have taken the car to 2 garages but because it is so intermittent they can not find the fault, also no error codes coming up on the computer.Could it possibly be the coil pack if it only happens once it is warmed up?i have tried spraying the cam shaft censor with freeze spray to see if that would make any difference but no joy.what ever the fault is if the car fails to start i leave for an hour or so and will start every time.Any advice would be really appreciated. I do not want go and buy a coil pack at £250 just find out that it is something else.Is there any test i can do to see if it is the coil pack?
The HT leads are a weak spot on this model. They tend to start to play up at about 30/40k miles. They are much cheaper than a coil pack. MX5parts keep them in stock. Spark plugs may need cleaning/changing at the same time.
Son's MX5 has started sounding as if it's missing on start up. No faults logged. He has been advised that the hydraulic cam followers may be draining. Next oil change will include an engine flush.
Hi Peter thanks for suggestion .
If its been left long enough it will start straight away but on the odd occasion when its been cooling down when i go to start it will start but it feels like it is only running on 2 or 3 cylinders this usually clears after a couple of minutes or a mile or so or if i leave the car to cool right down it will start and run perfect.I have tried spraying the cam shaft censor with plumbers freeze spray the last time it did not start but never made any difference but i am not sure that would rule out the cam shaft censor.The last mechanic says that if when turning the car over if the rev counter works it usually means the crank censor is fine.
Thanks for your reply mjm ,the car has done 44k so its certainly worth trying new ht leads before spending £250 on a coil pack.The suggestion from David about the coolant censor also sounds like a good idea so i will give that a go first.
Thanks again to everyone for all your suggestions and anything else that you can think off will be greatly appreciated.As soon as its sorted i will let everyone know exactly what the problem is.
Hi Bill, I have EXACTLY the same problem with my Mazda MX5 2000 model. Again, no one can detect what the problem is and again, I have been advised to change HT leads and coil pack plus a heat sensor somewhere...!! Have you had your fault rectified..? If so can you confirm what it was..? I'm at the point where I'm about to throw the 250 quid at the mechanic.. Thanks for your help - Paula
Hi Paula,Still no joy with my car yet!.I am getting an auto spark to look at it on Monday or Tuesday hopefully he will come up with an answer.If you can wait another few days i will let you know how i got on.or you can email me at email@example.com.
Hi Bill, I'm not in a rush, I'm about to go on holiday so won't be using the Mazda for a few weeks. I'm now using my husbands car for the short trips that make the Mazda fail and he uses it for the longer journeys which it appears to be fine with. I think I might phone the local Mazda service department and pick their brains to see if they've had anyone bring in one with the same issues.. It's a shame because there's someone else who's had the issues and asked the Honest John forum for help last October and I've added a thread to her query but if she's resolved the problem then she won't be looking at the site anymore. I'll let you know what the Mazda service department say (if anything !). Thanks Paula
Cheers Paula,i will let you know how i get on next week.I went for a short run yesterday to the shop and back about 1 mile or so, i went to start it 5 minutes later and it would not start i tried again every hour or so but no joy,so i left it for about 8 hours then tried it again and it started with 1st turn of the key!.does this sound like your problem? anyway hopefully next week it will be resolved.
Bill, Have had a breakthrough.. I think... One of the guys who looked at my car initially doubted my issues and try as I might I could not replicate the mis-fire or non-start for him. He did say however, that if I experienced the above that I should contact him if I was stranded and that he would come out and check that there was fuel in the chambers. At this point you'll have to excuse my engine language... So there we go, drove from the train station tonight and parked up at the supermarket and lo and behold it wouldn't start. So I phone the "guy" who turned up and asked me to turn the car over where he took two of the leads off the head (on opposite sites of the coil pack) ad pronounced that there wasn't a spark.... exactly as you'd had... he then got a further electrical tool out and put it in the connectors on the top of the coil pack and earthed it on the engine and then asked me to turn the engine over again. It fired up, but only on what I would describe as two cylinders... he then put the probe (again excuse my lack of mechanical knowledge) in all the tops of the coil pack electrical connections whereby the car sprung into life and started firing on all cylinders. He did this time and time again as he couldn't quite understand what he was experiencing and eventually said that it wasn't the coil pack (excellent saving a few hundred quid) but that it was probably the ECU circuit board that possibly had a faulty transmitter. He's going to try and find someone to check the circuit board (he says that this is probably why it intermittant as the circuit board is inside the drivers footwell and subject to the heat in the car (and not the engine) and to see if there is some wear and tear on the transmitter.. Bill, it certainly makes sense as clearly the fault is temperature sensitive and if no-one has been able to find an engine flaw then this might be the case. Anyhoo, he's going to take it out and take a look, perhaps get it tested if it doesn't look corroded or burnt out.... watch this space and I'll let you know... One step nearer 'eh at no further cost other than a pint for the mech ! Regards Paula
Cheers David i will give this a go first as the fault only seems to happen when the car is at a certain temp.when it does happen its when the car has been warmed up then stopped and cooling down for about 10 minutes or so.Whatever the fault is it needs to be more or less cold before the car will start again.it never happens just after you turn the car off it has to sitting a while, it all depends on the outside temp at the time,the milder the weather the more the fault occurs.sometimes it will go a couple of weeks with no problems then it could happen every other day.Its just unfortunate that every time i have taken it to the garage it starts every time with no error codes showing on the computer.Anyway thanks for your advice i will get the censor changed and let you know how i get on.
Hi Guys, i have had the coolant censor renewed the crank censor renewed,the cam censor renewed, new plugs and new leads fitted but the the problems still there.it did appear to be running a bit smoother after the coolant censor and plugs were fitted for 3-4 weeks.but then it started to miss again once it had been warmed up and in the last couple of weeks it has failed to start 3-4 times after it has been warmed up!. I have been advised that its not the coil pack because the coil pack is split in 2 parts and when the car fails to start it there is no spark from any of the leads 4 leads and that if it was the coil pack it would still be firing on 2 cylinders.can anyone advise me if there are any other censors that detect the engine temp that would cause this intermittent fault ? as i have said this only happens once the car has been warmed up and switched of for a period of time usually about 10-15 minutes or longer depending on how long the car has been running.the other day because it was sitting in the sun all day at my work it only just started with a bit of a back fire after sitting for 8 hours which seems to be pointing to some sort of engine temperature censor fault if there is such a thing?Any advice would be greatly appreciated as i am at my wits end with this car.So much for the MX5 being totally reliable and bullet proof, i have spent a fortune trying to sort this problem and i am no further forward.
Taking a different tangent... How about some injector/fuel system cleaner? You seem to have replaced the most else. Failing that the only thing left is the coil! Forte Injector cleaner & Advanced gas treatment (put both in on 1/2 tank of fuel) have worked for me in the past.
Ok - attempt two - poxy forum software bailed the edit of the previous post....
How about using some of the HT Lead Ignition Spark Tester adapters that fit between the sparks and the leads, leaving them on and when the problem occurs - quickly pop the bonnet and see if your getting 4 flashes?
Thanks for your suggestions James but fuel problems have been ruled out by 2 different mechanics and although the coil packs not been ruled out it seems most unlikely because it is in 2 parts and for both parts 2 fail at the same time all the time is almost impossible.Its looking more and more like an electrical fault but finding it is the problem,but thanks again for your suggestions and any more that you have would be much appreciated.
when it fails, have you actually checked it has sparks?
Get a spare spark plug, take a mate out in the car, warm it up to make it fail and when you are in "no start" mode use your spare plug against the engine block to check good strong sparks in each lead.
yep I have tried this and it is not sparking on any of the 4 cylinders, hence the reason i am ruling out the coil pack.but thanks for your suggestion and keep them coming please they are all appreciated.
Hi Bill, you'll need to read my reply from last night and then this reply will make sense. I've found a website that's worth a tap at... this is what's on it:
Mazda common ECU failure symptoms
All Mazda cars fitted with Mitsubishi Electric electronic distributors are prone to breakdown caused by electronic failure of distributor. We can rebuild some types but in most cases we will need to see the distributor before quoting for a rebuild. Please can you complete the quotation request form found by clicking HERE.
1) Vehicle suffers breakdown when engine warms up. Usually this starts as a rare occurence but gets worse with time. Breakdown services diagnose breakdown caused by loss of spark. Vehicle usually restarts when allowed to cool down.
Web address www.carelect.demon.co.uk/mazind.html
I'm going to get a quote, I think they're in the isle of wight and deal with the ecu's by post. Would be worth seeing what you're auto thingy man says...
Hi Paula,It looks like you are on to something here,everything your mechanic says seems to make sense so i will pass all the info to the auto spark on Friday and see if he can do the checks at his workshop.But it looks like you have cracked it which has just made my day in fact its made my week! Thanks Paula,As soon as the auto spark lets me know what to do next i will get right back to you.
no probs Bill, I'll have a go at getting my ecu out at the weekend to check if for residual damage (if I can find it that is !!) Even if it doesn't look damaged I think I'm going to send it away for checking provided that it's not too expensive. At least that would eliminate or rectify the problem. Still haven't spoken to Mazda - I'm almost sure though that they won't admit to any "faulty" things on the car and will insist I take it in.. not doing that.. far too easy and expensive !! Let you know how I get on at the weekend. Nice to be of help to someone for a change !
Hi Paula ,just a wee update the auto spark still has my car he has found a fault with 1 of the coil packs so he is currently trying to seek a cheap replacement as he is still not sure why a fault on 1 coil pack would stop the car starting!he did go into some technical detail about transistors sending messages to the ecu unit but until he tries fitting a new one he wont know for sure.Hopefully he will be able to source a cheap one in the couple of days,watch this space i will keep you informed.
Hi Bill, thanks for that.. My mechanic had to get me the part numbers for the ECU as he said it was a bit more complex than unclipping a cover (oh silly me the female!!) Anyway, my husband took the car to him and he said that the bolts on the cover had all corroded and had to use quite a lot of force to get them to come off. I've got the numbers I need now to get a quote but the other thing the mech said was that the passenger footwell was quite wet and that there could be water seeping into the ECU which would cause the same issues... I have to say that I think that I only have problems starting it when it's damp or wet weather... The last time I couldn't start it I took it to the supermarket and it hammered it down while I was in there. Check your passenger footwell for damp/wetness just on the off chance. He did say that I need to check for leaks which is on the list of things to do "just before the holiday". Good luck and let me know how you get on. Thanks Paula
Hi Paula, bad news its the coil pack!!!!! its going cost about £300 to sort.Mazda have plenty in stock as this is apparently a very common fault and is almost certain to fail after about 50,000 miles!!.anyway i hope thats not whats wrong with yours.Thanks for all your help and i hope your wee car is sorted soon.
The favorite place for MX5s to leak water into the cabin is from the hood drains.(unless the hood is split ! )
These drains are at each end of the hood, behind the doors. You can't see them with the hood up. The one on the driver's side is easier to see than the other. Dead leaves and general road dirt tend to block them and the trough they drain overflows into the cabin. A good poke about will clear them. Check that they drain ok into the door sills and that the drain holes in the sills are clear.
Hi Paula, just to let know my car has been running like a wee sweetie for a week now so touch wood thats the problem sorted .The auto spark told me reason the coil pack is so expensive £260 is because unlike normal coil packs the mazda is full of electrics,resisters switches etc and even though there was only a fault showing on 1 coil pack they are all inter connected through the ECU hence the reason sometimes firing on 2 cylinders and sometimes not staring at all, anyway it was all to complicated for me to understand but the main thing is that it seems to be sorted.My advice would be for you to forget the ECU and get the coil pack checked by an auto spark.if there is a fault he should be able to find it.I hope its something cheaper but as i found out the hard way by trying and buying everything but the coil pack i would try the coil pack first.
Hi Bill, thanks for that. Just back of the hols and the mechanics had dried the car out completely. Went for some shopping and it had a bit of a ropey start at the supermarket. Are the autospark people part of a group..? if so, do you have a contact number and I'll certainly call one out. The ECU quote came back at about 160 quid.. the mech said there's someone a bit more local than that. Might still go down that route. note for MJM: yes, the drain holes were totally blocked and the roof is leaking - thanks for the tip though. Bill - thanks for your help and I'll certainly follow your advice.
just a quick update and closure to the fault. I've had the coil pack replaced and the car is running perfectly. Cost £218 from mazda parts internet site. It was certainly worth the further investigation before spending the money. Thanks everyone for all your help and input.