My nephew just replaced engine in '97 \Chevy Suburban, now no fire, won' start, any ideas ?

May be the Ignition Control Module in the distributor, that can be tested at Auto Zone, Make sure there is 12V at the coil, test light is fine to use, And make sure you are checking for spark from the coil.

Yes, getting voltage to coil, but nothing at coil tower, checked with inductive timing light, nephew replaced pickup in distributor and rotor, cap & wires, still no spark.

Check the Ignition Control Module, it took the place of the old point system. It is just under the distributor cap and can be removed without pulling the distributor.

Replaced that also, known as camshaft position sensor, also ignition control module located next to ignition coil, both are replaced, still no spark.

Ok you probably are right on the location of the ICM, it may just be bad, I would have it tested. This is not the cam shaft sensor.

It looks like it sits on a finned heat sink. Make sure and use the dialectic grease on the mounting side of the ICM.

No, I know where and what the parts are, it's my nephew's truck, I'm just trying to get answers for him because he's hard headed and won't listen to most of what I've told him on this, I figure if he gets the same answers elsewhere maybe he can get it going on his own, I agree with you on the diagnostic procedure, but, he is harder to relate these to. Thanks for the help so far !

OK, that ICM was replaced, but came from his previous engine, although it was running, I'm wondering if the ECM is not allowing it to fire , given all the changes?

Yep, I agree with tennisshoes suggestion also.

No, something is wrong, ICM should be tested. I just helped a guy and his new coil still was bad, I'd have that tested also.

He claims to have checked the timing in the manner you describe, I'd do this all for him , but I'm not in physical condition to get under hoods right now, all I can do is observe and advise, Hopefully he'll read your answers and learn something.

That was my first guess was coil itself, as I had similar problem with my '97 Chevy pickup, as soon as I replaced coil and had good charge in battery it fired right up, but kids today don't like advice from us old schooler's, even though the basics haven't changed. He is wanting to go under dash, and thinks it's security system issue, but vehicle has no such system,.

Thanks for all your help guys, I know you don't get paid for this but maybe he'll appreciate your answers, Thanks again!

Yes it does have a security system, but it is designed to just shut down the injector pulse to cause a no start. You would still have spark.

I'm not sure on the security issue, but he has no alarm control fob or any keyless entry system, so I don't know how it would activate besides a key chip which he doesn't have, so, I still don't think that is the problem, I have heard of needing re-learn when replacing crank sensor and others though, of course that would be difficult for him to do.

You do not need to do a relearn for the crank, or cam sensor. It is done for the Body Control Module replacement. And no the security is not the issue.

Thanks again, I wasn't sure about that relern issue and it didn't seem viable given these parts are in Autozones everywhere,