RunninOnEmpty

iTrader: (5)

Hoping someone has some recs. Swapped my valve stem seals after running leaky Supertechs for several years and making do by topping up oil. I've done two timing belt and WP changes on Miatas several years ago, no problem. So I figured valve stem seals would be easy, though I've never removed the camshafts or caps. Seals installed with head remaining on block.

But the car won't fire. It'll turn over, and I smell a bit of fuel on the plugs.

Looking at my boost gauge, it sits at *0 psi* when trying to turn over. Is this indicative of a problem? I would've figured I'd get some vacuum as the engine turns over.

Applying throttle isn't changing startup behavior. Once in a while it may catch for a split second, but ultimately dies. So I think it's spark related, not vacuum. Applying the stem seals seemed easy, but maybe I missed something.

Notes:
- NB1 so has the CPS on the valve cover. it's too simple to have messed up.
- Crank sensor wasn't touched.
- Cam gear kept with camshaft, so no chance of being on the wrong dowel.
- TDC seems right, turning the crank by hand always results in I and E straight up top.


Any advice appreciated, even if it's ways to cut corners so I don't have to reinstall everything just to test the car.

Thanks,
Jon

patsmx5

iTrader: (16)

coil pack plugs reversed.

RunninOnEmpty

iTrader: (5)

Thanks Pat, I'll take a look. Pulled the scanner and it says P0339, Crank Position Sensor. I don't see why it suddenly errored out as a coincidence, but I know they're finicky enough just to replace them. I didn't touch this area at all.

Thanks for the tip.

hks_kansei

Check the crank sensor gap.

Too close and it will hit the nubs, too far and it wont pick them up.

I cant remember the proper spec, but should be easy enough to look up, then just a 10mm spanner and a feeler gauge to set the gap.

borka

iTrader: (1)

Run a compression test. If no vacuum, then might be no compression.

RunninOnEmpty

iTrader: (5)

Guys, thanks for the replies. The problem did end up being a new Crank Pos Sensor was needed, I guess I was even lucky enough OBD2 logged it, or I would've been way stuck But a compression test did help to determine that my install wasn't bad, and lo and behold, I hastily copied pic off the internet of an NA 1.6 - wires are a different order.

Still have no idea why the Crank Sensor suddenly died during this project, but better in the garage than nowhere.

Bigger lesson learned, I should've removed the wideband sensor with all of the troubleshooting. Pretty sure it's gone now that it's been washed with fuel.