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Discussion Starter · #1 ·
I rebuilt the engine on my 1991 Miata, I got it all back together yesterday, we tried starting it up, it will crank and try to start, but it just won't start. I checked all the wires I have spark, I have fuel, everything I believe is lined up timing wise, I will have to triple check it, but no dice.


The things I did notice, are when cranking there were intermittent times where nothing would happen the starter was going, but it sounded as if nothing was happening in the engine and the engine back fired a couple of times.

I am going to try turning the Crank Sensor (tightening it a little bit), and see if that does the trick, and if that doesn't work I am thinking I will take the Cam Angle Sensor out and turn it 180 degrees see if that helps my plight, but any input or experience would be welcomed.
 

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Have someone else check the wiring too. Two sets of eyes are better than one.
 

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Discussion Starter · #5 ·
I marked and labeled all of the wiring when I pulled the engine, and triple checked it after I put it back in, I believe the wiring is all good, but I will check my grounds. On a side note I noticed my exhaust cam doesn't turn as smoothly as the intake cam could this be an issue?
 

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Discussion Starter · #7 · (Edited)
That I understand, but when I was lining them up, to get them TDC, when I turned the exhaust cam it didn't feel like it turned as smoothly as the intake
 

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1. The lifters may not have oil in them yet so the valves are not opening correctly yet; or if you filled them with oil, the excess oil is causing the valves not to close. So it will take a while with the cam in different positions for the excess oil to bleed off.
Even after it starts, there will be a lot of clatter until the lifters are filled. It may take several start & stop cycles for the lifter to be right.
2. Keep changing your cam position sensor a little to get the timing close to where it wants to start.
3. Check to see if your plugs are fouled from excess gas being pumped in. You should pull your fuel pump relay and try squirting some starting fluid in each cylinder to get it to pop.

i had the same problem after an overhaul and it was a bear to get it started and it took several overnight sitting cycles to get it sorted out; but after a few days, all lifter ticking went away and it idled smooth. It takes time.:mrgreen:
 

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Discussion Starter · #11 ·
I will play with the timing here in the next day or so, and I will let you know how of goes thanks
 

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Discussion Starter · #12 · (Edited)
UPDATE: This is just getting ridiculous, I have spark, every plug is firing, every injector is working, the fuel pump is working, the wiring and hoses are good, the grounds are cleaner than ever, but still no luck I checked what engine codes were output it said mass air flow sensor, so I got that fixed, still no luck. Now it isn't putting out any codes. Could it be one of the sensors? Crank? Cam? I am at a loss, what do you guys think?
 

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My money says you have the cams backwards. Post a pic of the motor at top dead center with the valve cover off. Preferably one where we can see the cams and one where we can see the timing marks.
 

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My money says you have the cams backwards. Post a pic of the motor at top dead center with the valve cover off. Preferably one where we can see the cams and one where we can see the timing marks.
No way the cams can be in backwards..the CAS mounts to the rear of the intake cam on the 1.6..and the exhaust cam has no provision...physically impossible.

I would disconnect the battery..again..reconnect and try to start ONE time, but let it crank for a bit. THEN check the codes for something fresh.

Of course there is the possibility that the timing is 180 off ...the first lobe on each cam should be pointed outward...
 
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