I have a 1996 Saturn Sl2 that I am having trouble diagnosing. The symptoms are it does not start when cranking, but starts easily and runs smooth when I coast start it.

Things I have worked on:
engine rebuild (rings, bearings, seals, and hone)
New icm, coils, wires, and plugs,
new starter,
new battery,
new fuel pump,
all fuses are good,
good alternator,
temp sensor isn't new, but works fine.
Starting fluid doesn't help, and it seems like there is no spark when cranking.
There is solid power getting to the EIS fuse when cranking so probably not a bad ignition.
The only thing I can think of is the crank position sensor, but it runs and drives fine once it's running.

Could you guys tell me what you think?
Thanks in advance.

 

Is it throwing any codes?

What's the resistance across the CKP? (Cold)

Does it EVER fire when cranking?
Does it EVER start by cranking?

Also, are you using stock NGK plugs gapped @ 0.040" ?

IN the dark
Pull the plug wires from the coil towers. Have someone crank the engine. You should see an arc alternating between the coil towers on one coil and the coil towers on the other.

What do you see.?

​​​​​After you do all that, what are the compression values from the post-built compression test? And how fast does the compression build in each cylinder to get to the max?
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I took off the crank sensor to check the resistance and found the bolt lose. I checked the sensor to make sure it was good, put it back on, and it started right up. It felt like the bolt was stripped so I put blue locktite on it and will hope for the best.
FYI, the test showed it was 768 ohms. From what I saw online it is supposed to be around 2000 ohms, but it seems to be working. I also found proper ac voltage when passing metal over the sensor.

So the problem ended up being a stripped bolt holding the sensor.

I did an intake smoke test and found a leak in the throttle body. Does this have a seal that can be replaced or do I need to get a new one? (Picture below)

 

Throttle body to intake gasket: Felpro 61177
$1.29 on Rock Auto ATM.

If it's leaking at the throttle shaft (can't tell from the pic) then that's a whole other kettle of fish.

 

I think 700 is about right. So it was out of position and not picking up a large enough signal to make the PCM happy.

What kind of vacuum do you read at idle and at 2000 RPM and does the needle quiver or stay still?

Remember that air is still considered metered air as it contributes to the manifold absolute pressure. As long as it is steady, and small, I don't think it would cause much of an issue. Measuring the vacuum should give you an idea. It's the unmetered air/ vacuum leaks like those around the intake manifold gasket that cause the nasty performance issues.

 

The only issue I see is that if the sensor was out of position, how does that change when you push start the car? No ckp signal equals no spark and no fuel at the injectors. It would have to remain in position the entire time.

???

 

I cannot speculate as to why the car would start only when pushing it. All I did was take out the ckp, wipe it off, test it and put it back. It now starts fine so that had to be it.

I will check the vacuum readings but I agree with you a small leak would affect the engine enough to warrant getting a new throttle body, especially at 260k miles.