'07 Mazda 3: Starts only when in Neutral

[Finz]

Daughter's '07 Mazda 3 w/ 2.3l will start just fine if cold. However, if running errands and get back into warm car, I have to shift the auto trans to neutral for the car to start. Absolutely nothing happens while in Park. I imagine there's a faulty interlock... but where is it located? Am I on the right track? Is it a royal pain to replace? Any insight would be appreciated Thank you. --bob

 

[Chester11]

Your timing is a little weird - I'm trying to fix the same issue on an 07 Mazda 6. I think the engines are are same (2.3). Where the shift cable connects to the trans - there is a large nut and washer. (Beneath the air box, down low). Mine is really rusted. As I understand it, the rust prevents the gear selector from operating to the park position. As a temporary fix, you can hit it with PB blaster. It fixed mine for about a month. Maybe start there first. The neutral interlock switch sits right behind the bracket - about a $100 bucks. But I would see if you can free the nut first before replacing the switch. I'm looking for a replacement nut and washer now - just haven't been able to get the nut loose and make it to the hardware store. (I'm too cheap to pay the dealer $8 for a nut and washer). There is a TSB on this for the Mazda 3 somewhere that shows how to do it. (Basically you hold the bracket with a crescent wrench to keep from damaging the switch, while loosening). Hope it helps. see: https://www.justanswer.com/mazda/4kafy-mazda-3-started-fine-neutral-it-couldn-t-put-back-park.html

 

[Finz]

That's great... thank you. So long as it's not a replacement of the ignition I'm happy Thanks again

 

[Chester11]

I'll let you know if I am able to fix it....

 

[miden851]

I’ve never heard of that one

 

[CharBaby]

I am assuming this is the 5 spd auto? Is the PARK Light in the dash & shifter lighting up? Try putting the shift lever into PARK with just a little harder push. I had the same issue several years ago on my daughter's '06 Mazda 3 in my signature. I had to adjust the "Transmission Rangefinder/Range Sensor" on the front of the tranny. It has two allen head screws. Loosen the screws(they don't need to be removed) and turn the rangefinder ~ 1/8" clockwise. The holes are oval/oblong for this adjustment. Sometimes it's hard to get to the RIGHT side allen screw but, it can be done. This is what the part looks like: https://www.mazdapartswebstore.com/p/Maz...&origin=pla

 

[Finz]

Originally Posted By: Char Baby

I am assuming this is the 5 spd auto? Is the PARK Light in the dash & shifter lighting up? Try putting the shift lever into PARK with just a little harder push. I had the same issue several years ago on my daughter's '06 Mazda 3 in my signature. I had to adjust the "Transmission Rangefinder/Range Sensor" on the front of the tranny. It has two allen head screws. Loosen the screws(they don't need to be removed) and turn the rangefinder ~ 1/8" clockwise. The holes are oval/oblong for this adjustment. Sometimes it's hard to get to the RIGHT side allen screw but, it can be done. This is what the part looks like: https://www.mazdapartswebstore.com/p/Maz...&origin=pla

That's fantastic.... thank you. Yes, 5 speed auto. You know, I can't recall if light on dash is up or not... I know N lights up. I think P is/was lit but I'll double check this morning If the weather cooperates today, I'll jack the car up and spend this week nailing it with PB Blaster. Hopefully by week's end, it'll be a breeze (wishful thinking) Thank you again

 

[Chester11]

Fixed mine this afternoon - hopefully it lasts. It's pretty easy, and I'm no super wrench by any means. 1. Remove airbox and hose from throttle body to give yourself room. 2. Hit the bolt with PB blaster and let sit. 3. Mine was a 21mm bolt. The frame prevented me from reaching from below. I used a long screwdriver to jam between the frame and the bracket. This kept the bracket from moving while removing the bolt. Access is the toughest part because a 21mm socket is big. 4. Once removed - hit the bolt and washer with some sandpaper to remove the rust. (I suppose if you had a wire wheel even better.) 5. Coated everything with anti-seize, and put it back together. I was going to buy a new nut and washer, but ran out of time. I was a little surprised at the size of the lock washer. I doubt something that large could be found without ordering the dealer part, or going to a fastener store. Hope it helps.

 

[meep]

sounds like the safety interlock switch to me. Fudging with the range adjustment may help at least for a short while but probably won't be a long-term fix. If it's an aisin trans the switch will mount flush to the side of the trans somewhere and you'll see a bundle of wires coming out of it. -m