I’m looking for technical help or recommendations on: starter issues
Hi everyone,
I’m throwing this open to the club as a matter of last resort.
Last year I bought an 2012 Venture Edition 2.0 PRTH Roadster (not that it should make any difference). I installed a Pioneeer SPH-DA230DAB head unit as all was well, for months. Now twice recently, it’s thrown the starter on while the engine has been running and there destroying the motor.
On the first occasion this happened, I tried to save a few quid and bought a used OEM motor, this lasted about a week, before the thing happened again, when it was towed back to the garage and the owner suggested it may be caused be a faulty ignition switch, so this time I bought brand new starter motor and ignition switch, which the garage duly fitted. a week ago. yesterday I went ot use the car to find the battery flat. so I went to Halfords and duely spent another £90 for a new premium battery.
I just fitted the new battery, started the car and after idling to aroung 5 mins the car turned on the start motor again!!! Now, When I switch off the car, it remains off, but as when I switch to run position, and wait about 20 second, the starter spins up and the engine starts and the motor does NOT switch back off!!!
Please help, I love this car, but its costing fear more that she’s worth in garage time, (I can’t put the thing up on ramp myself as I have nowhere to do it.) I can’t sell it like this. (I don’t want to either), but I cannot keep it as a giant paperweight.
If anyone know why this may be happening I will accept all suggestions, (All the fuses have bee replaced. yes I do mean ALL).
I’m hoping that one of you MX5 gurus out that might just have encountered this symptom before and be able to save my sanity.
Please, if you can help, I promise to pay it forward.
Have you checked for water ingress in the passenger foot well. It comes in via the scuttle grommets, gets in the ‘electrics’ and causes weird ‘happenings’.
I was about to suggest the same as Malc. It’s just one easy check before delving deeper. We have had an avalanche of rain just lately too, take a look.
I confess, that I haven’t although I have the parts in to replace both, I simply haven’t gotten round to it. I assume that the passenger side foot well carpet would be damp if that is the case. However, I’m going to take your advice and replace them this evening after work.
Thank you for your suggestion, every straw being thoroughly clutched at.
I’ll drop out the glove box, that provides a fairly clean line of sight.
My first thought was, “Holy Cow, somewhere else to treat for rust”, then I took a breath and accepted it as part of MX5 ownership.
Process of elimination, water ingress has in the past caused weird happenings on NC’s to members cars. I remember one saying he had to replace the loom (partially) as it can affect all manner of electrics. Light’s coming on randomly, car won’t switch off etc. If the fuses are wet it’s a starting point to get them dried out.
I suppose the starter motor problems happening twice could be unrelated to water ingress but of course don’t count it out, rain and more rain, can get to the same places.
I’ve just been in my garage, saw a puddle by the front wheel. Last year I sealed all entry points for rainwater to get in under the door, it’s found its way in again, blooming weather.
second starter in as many months, this one was a brand new Henkel Parts 3111554 Starter motor for MAZDA MX-5 III (NC) from AutoDoc.co.uk. Not the fastest delivery, but much better than the £440+ that I’ve seen for a Lucas model. I also got the garage to fit a new ignition switch in case that was faulty…
I can rule out the starter, and integrated solenoid. I doesn’t explain where the solenoid would be getting it’s power from. I feel that something is energising the starter relay coil, and this in turn is exciting the solenoid. This feels to me like there is a higher than average chance re Mad_Malc’s idea of water ingress. I just completed the replacement of the little white screw posts and, the foam “gasket” under the passenger side one was soaking and breaking up. I wasn’t able to silicone around the new ones yet, but I will first thing and makes sure it’s water tight.
Thank you for your suggestion, it is appreciated and there is no such thing as a bad idea.
Until you get to the bottom of it, I’d be tempted to wire the solenoid trigger wire to a switch. You can’t keep chucking starter motors at it.
If you were to maybe wire a bulb or buzzer to the same circuit, you’ll see when the fault occurs.
A switch would also double up as a security device I suppose
Not sure but is there a separate relay in the fuse box , or is the fuse box starting to corrode , I had a car years ago wouldn’t energise the solonoid if I removed and refit the relay it would start it was the fuse box connectors , could a defective relay / fuse box cause a unwanted feed ?
Have you checked the wiring coming from the ignition switch? Something could have been provided with a power supply from a wire there and it is making contact with the stater circuit somehow.
Firstly, let me say a HUGE “Thank you” to everyone that took the time to read and answer my question.
Now the outcome:
Yesterday before close of play. I was able to replace both scuttle grommets on the advice given here. Fortunately, I already had the parts in. I noticed while taking the old ones out the the rather dubious neoprene “gasket” that they sit on were rotted out and leaking. I had to take the front apart again first thing to apply silicone around the grommets as the seal here is basically woeful, and just waiting to leak. I managed to start the car as it had had all night to dry out a bit, and left the windscreen blower on hot with the fuse bay door and glove box open for almost three hours. I checked by getting my hand up behind the dash it was toasty warm. While warmth does not equal dryness, it’s a good indicator of a drying force up in there. The self starting issue has completely stopped and the phantasm has apparently been exorcised!!
Thanks loads to all who suggested caused and cures, especially Mad_Malc who came in with the fastest, cheapest and working fix. Bravo sir!!! I own you one.
The moral of this tale is this: If you get a sense that a job needs doing, and you go as far as to get the parts in… Do the bloody job! It could save you hundreds!
(Two starter motors, one ignition switch, one battery, and £400 in labour in my case)
