Engine Won't Start?

Check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light.

Yup. It's common to go through four to six replacement generators on GM products built after they redesigned them for the '87 model year. Two failures so close together though suggests a problem that should be addressed by the part's warranty. You already did the number one thing that reduces the number of repeat failures. That is replacing the perfectly good battery unless it is less than about two years old. These generators produce huge voltage spikes and the battery is key in controlling them. As it ages, the battery loses its ability to dampen and absorb those spikes even though it cranks the engine just fine. Those spikes destroy the internal diodes and the internal voltage regulator. That's what happened here. The only way to get 18 volts is from a shorted voltage regulator. BUT, ... Since the battery is new, I suspect the voltage regulator may have just failed on its own. There can also be a bad batch of them that were supplied to the rebuilder so to be safe, you might request a replacement generator of a different brand if the parts store has them.

Try resetting it normally a remote is not required for this. worst case a mechanic will need a scanner to reset it which most garages can do. See our link.
https://www.2carpros.com/articles/how-to-reset-a-security-system

Water has got into an electrical connector and is causing an open or short circuit.

You will probably have to remove all connectors that were under water, disconnect and spray with an electronics cleaner, then blow dry with compressed air.

Hi there,

Run a scan and check for any unresolved fault codes first, also it would be good to be able to check the fuel pressure when it fails, although this may be hard to do.

Mark (mhpautos)

Hi Richard.

Did this just happen since you replaced the radiator? Have you checked to see if there is spark and fuel to the engine? One must be missing for it not to start. I assume the starter is engaging and turning the engine because you mentioned you can tell the battery has power.

Do me a favor, my first suspect is that you disconnected something by accident related to the ignition system. For example, the crankshaft position sensor was disconnected. Lets first start by checking for ignition spark to the plugs.

Here is a link that shows how to do it:

https://www.2carpros.com/articles/how-to-test-an-ignition-system

If there is spark, the next thing to do is check to see if there is fuel to the engine. Here is a link for testing:

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

An easy way to check if fuel is the issue is to see if it starts for a couple seconds using starting fluid. If it starts and stalls, then we know if is a fuel related issue. However, I did include the link for testing fuel pressure.

Here is a link that explains the most common causes for a crank no start condition. Take a look through it to see if it helps.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Do these checks and let me know what you find, or let me know if you have other questions.

Take care,
Joe

Hello,

Does the engine crank when you turn the ignition key to start?

Thanks,
Alex
2CarPros

Hello again,

Okay, I hate to be the bearer of foreboding doom, but I have personal experience with this engine through a Cobalt my Father owned. He came back from the grocery store and parked in the drive way, went out to start it the next morning and it was a no start. What had happened was somehow, and these engine are notorious for doing this, it jumped time? I, for the life of me, don't know how, but it ran absolutely perfect one minute, and with absolutely no warning what so ever, had jump time, and being a zero tolerance engine, had bend valves in the cylinder head and basically destroyed itself. His car had 80,000 well maintained miles on it.
Having said that and probably scaring the crap out of you, very sorry for that, just thought I should share my personal experience with you, for whatever it's worth, let's see if can figure this problem out. I think you were on the right track, let's check for spark first. I have included a link for you to go to down below.

https://www.2carpros.com/articles/how-to-test-an-ignition-system

Please go through this guide and get back to us with what you find out.

Thanks,
Alex
2CarPros

Hello,

It sounds like you lost the timing chain but to confirm the failure can you do a compression test? Please follow this guide.

https://www.2carpros.com/articles/how-to-test-engine-compression

This guide can help as well.

https://www.2carpros.com/articles/car-cranks-but-wont-start

Please let us know what you find. We are interested to see what it is.

Cheers, Ken