NB8A won't start

Mr Morlock · Postby **Mr Morlock** » Thu Sep 25, 2014 11:13 pm

Subject is MX5.

sabretooth · Postby **sabretooth** » Tue Sep 30, 2014 5:22 pm

I'd look harder at the CAS if I were you. I had an almost identical problem in my NA8 which grounded my car for weeks. In the end it was the CAS despite it seeming to work okay.

Try borrowing one from someone.

slyfox2151 · Postby **slyfox2151** » Thu Oct 02, 2014 3:10 pm

Check the 15amp engine fuse in the cabin next to the driver. I had the same problem today, the fuse was blown.

No spark no start.

Dommer · Postby **Dommer** » Tue Oct 07, 2014 7:10 pm

My NB8A won't start since Monday morning after I wash / degrease the under tray around the pulley area on Saturday. Although, I have back it into my carpot from the drive way on the day, and I have left it over the whole week end to allow the moisture to dry up. Still won't start today, so I have to get my hands dirty this morning, and end up undoing the Crank Angle Sensor, gave it a good clean and dry it with a hair dryer, my MX burst back to live, and started again. Some experience, still fresh, like to share. Test the CAS in the car is easier than on bench. All you need is leave the igniton on as driving, then flick some iron obect, like screw driver or socket extenion bar across the sensor, you can hear all the injector solenoid firing, if the sensor works. The CAS is also identical to the one used in Mazda 323 BJ model (found out from some ebay advertiser). Just come back from Jolly DIY Wrecker in Melbourne with a spare one, just in case, and it only cost me $23.00. Also, don't put the sensor too close to the pulley, Inititally i had it set to about 1 mm from the marking notch, I think it was too close, won't fire, the senor cannot distinguish the pully and the notch mark, i end up adjusting the gap around 2-3 mm between the notch and the sensor, a bit of trial and error until the engine fire. And it is easier access to the sensor, with the air hose between the airbox and intake manifold removed, during trouble shooting.

gslender · Postby **gslender** » Wed Oct 08, 2014 6:59 am

Just be careful firing the injectors like that, you can get a back fire and real fire and/or hydro lock if you flood it too much.

Dommer · Postby **Dommer** » Wed Oct 08, 2014 7:06 pm

gslender wrote:Just be careful firing the injectors like that, you can get a back fire and real fire and/or hydro lock if you flood it too much.

Good point, should leave the spark plugs off while testing allowing the fume to vaporise. Many thanks for picking that one up.

samx5 · Postby **samx5** » Thu Oct 16, 2014 2:46 pm

To the OP, as per similar thread, I had this issue, turned over and fuel was pumping but didn't fire. After process of elimination I replaced cam position sensor and all is good, around $70.