Another "cranks but won't start" thread
 

Pulled the engine to do a reroute, install an oil cooler, and replace the front and rear main seal (again). (car is a 99 NB, stock ECU, minor bolt-ons, no turbo).

Engine is back in now, but the car won't start. Here is what I know so far:

Electronics
1) All the sensors are plugged back in (MAF, CAS, CPS). I checked the gap on crank position and its good. I DON'T have the coolant temp sensor plugged in at the moment, but I don't think this matters?

Fuel:
1) I am getting fuel. I smelled fuel on 1,2 and 3 (haven't checked 4 yet, will check tomorrow).
2) shorting GND and F/P indicates the fuel pump is alive.
3) Car started backfiring while trying to start it.

Spark:
4) I am getting spark on 1 (I will check 2,3, and 4 tomorrow).

Timing:
-I removed the cam gears to get the timing plate off so I can plug the front of the engine.
-I marked the dowels + gears and put them back on. Is it possible to fuck this up? This is a 99 NB, so the intake side has to be "correct" or the sensor will not read correctly (I think).
-If I fudged the cam gear, I am assuming there will be spark, but it will be at the wrong time right?

Otherwise, my timing is "spot" on. I realigned the crank, I have I at 90* on the intake, and 19 teeth between the two marks on the cam gears. Pully Boss is also at the top when the crank notch lines up with the arrow.

Any suggestions or advice here? I did blow the IGN key fuse earlier, but I think the only thing that's on it is the Instrument cluster, starter, and the "Transmission Range" switch.

Backfire with no-start - timing brah.

Did you change anything with regard to the spark plugs? Swapped the coil pack plugs?

Can we see the timing alignment for the cams in a picture perhaps?

Can you put a timing light on it while cranking and see if it is anywhere close?

To Six and Fooger do you listen.

Let white paint be obtained, and applied onto crank pulley surrounding timing notch in a great swath, that its position be obvious. Crank engine while observing timing on #1. Is timing mark 180 degrees away from where it should be?

Ignition coils are easily switcharooed. Perhaps the low-side wiring is swapped, perhaps the high-side wiring is. Looking closely at the low-side wiring, the connector with the brown/yellow wire should go to the coil to which are attached the 1 & 4 plug wires, and the brown wire (no yellow) to the 2 & 3 coil. Verificate.

Cam gear. Two ways can this be installed, that only one shall yield correct results. A clear, well-lit and well-focused image of the cam gears shall be posted, while the crank be at the #1 TDC position and the cams in alignment with their reference marks. Unintuitive is the labeling of the cam gears, for E aligns I.

Marveled oft have I at this.

I will remove the dampener and take some pics. I still have the nail polish on the cam gears and the dowel. I am pretty sure those are correct, but maybe my timing belt jumped a tooth on the crank.
(I am going to be pretty pissed if my intake cam is 180* off. fucking FSM is so vague about this...)

I really think my problem is timing though. The coil pack is relatively new and the only fuel related thing I touched is disconnecting the line and reconnecting it!

On the "NB" coils, one wire is marked with blue electric tape and a blue dot on the coil. I will check the wires (if they correspond in color), but I did remember to put the blue marked connector to the blue coil.

It'd be pretty hard for your cam to be 180 degrees out of phase, to be honest.

The intake cam on #1 should be pointed towards the passenger side of the engine bay, and the exhaust should be pointed towards the driver's side.

Maybe you put the intake cam gear on the exhaust cam and vice versa - are those gears identical in design? Not sure if the camshaft position sensor on the intake cam means the gears are different. If the gears are identical, then perhaps you swapped the gears when you put it all back together.

If in doubt, ignore your paint markings and align per the FSM.

Ok the long awaited pictures of excitement.

-Here are the cam gears, you can see where the dowel markings are above the washer+bolt. (intake I at 90*, dowel at the top, same with exhaust).
https://www.miataturbo.net/attachmen...ine=1364586417
https://www.miataturbo.net/attachmen...ine=1364586417

-Here is the crank
https://www.miataturbo.net/attachmen...ine=1364586417
https://www.miataturbo.net/attachmen...ine=1364586417

-Here is the coil pack.
https://www.miataturbo.net/attachmen...ine=1364586417
https://www.miataturbo.net/attachmen...ine=1364586417


I don't see anything wrong with the timing honestly. 19 teeth, I/E and the dowels match the FSM:
https://www.miataturbo.net/attachmen...ine=1364586417

I was thinking maybe the intake could be put on "incorrectly" since those 3 notches are needed for the cam sensor, but I couldn't figure out a way to put it on incorrectly AND still follow the FSM.

Only thing I can think of is possibly one coil is gone? or maybe one of the sensors is intermittent?

hmm, I read this guy's thread about "intake backfire" and it reminded me of some seriously scary sounds coming from my intake when I was cranking sometimes (and sometimes right when I stopped)...

But that thread pointed to timing, and mine looks...better. Any ideas?

Have you checked spark on 2, 3, 4 yet?

Not yet, my shit is all apart right now. I want to rule timing out first (since I can fix that now).


I got an idea...could it be my CRANK timing plate is backwards?

having not worked with anything with a crank trigger, my guess is that its possible. the timing looks fine to my eyes on the crank and cams. The 99 trigger wheel is one of those oddly patterned ones, correct?

I think its the timing wheel on the crank. at TDC (ie with the eliptical notch facing up), the teeth would not match this FSM picture if it was flipped backwards:
https://www.miataturbo.net/attachmen...ine=1364589063

https://www.miataturbo.net/attachmen...ine=1364589063


This also explains the backfiring, since the crank would be 90* off?

haha that FSM section in my last post was actually about the notches on the dampener. Whatever, it got me on the right track.

I put the timing wheel in (opposite of my picture) and it started right up. All is good in my world now.

YOU CAN DO IT!!! (good luck gettin' a trailer lol)

It feels good when they finally fire up after giving you heartburn. Glad it worked out.