sl1m3r4l

Hello!
I drive a 1997 chevy express 1500 (specifically a mark 3 although a lot of the aftermarket trim is removed). Recently I started experiencing a crank no start issue out of nowhere. I believe this may be connected to a faulty antitheft system but there are several factors really confusing me right now.
1. I can't figure out what antitheft system is actuallt supposed to be in my van between VATS or passkey or passlock. I'm also not sure if Mark 3 changed anything about the antitheft system.
2. I bought my van used in pretty rough shape and clearly the antitheft system has already been messed with. Before my crank no start issue, I could just start the van without even using a key and just by twisting the lip on the ignition cylinder with my fingers. It was working like this for almost a year before this issue suddenly appeared. I also have never seen the security light appear on my dash. I have had to repair a lot of wiring issues so I wouldn't be surprised if the wiring going to that light is messed up.

Any insight into what's going on would be very appreciated. I'm having trouble diagnosing the issue because right now I'm not even sure what antitheft system is supposed to be in the van. Also maybe important: the first time my van wouldn't start, a few days ago, i found this YouTube video: https://youtu.be/a4l5NiLnjiY and it fixed my issue for a few days. But now it's back and the trick isn't working anymore.
the only way I can get my van to start is by spraying something flammable down the air intake, and it stops running when the spray is stopped. I have verified that my fuel pump relay is good and I can hear the fuel pump making noise when the ignition is turned on.

William Kisselstein

The problem may actually be the fuel pressure regulator. When it fails, the fuel all just cycles back to the tank rather than go to the injectors. So it will only run if you hit it with start fluid.

The part is pretty cheap, you can get them on Rock Auto for like $25, but changing it is a pain in the rear - it's under the upper intake manifold on the left side of the engine. Once you get to it, it's just a clip, but getting to it you'll curse the GM engineers, their children and their children's children. There is a youtube video doing one on a pickup and it took him about four hours.

I would imagine you can crank and pull a plug and see if it's dry. If it was the antitheft system, I believe those all cut the ignition circuit, so you can check for spark at the plug wire. If it's getting spark that rules out the anti-theft, then if the plug itself is dry no fuel is getting to the engine which again points to the regulator.

sl1m3r4l

Thanks for the reply!
im definitely going to check out the fuel pressure regulator and try to do some tests on it. The thing I find confusing is that it just went from working perfectly to not turning over at all. And then i got it to turn over with the weird key trick (I know it could be a coincidence) and it didn't run rough at all or have an issues for a few days. Now back to just not starting at all. It seems kind of strange to me that the pressure regulator would work intermittently like that with no symptoms of failure when the engine actually starts. Is this something you've ever seen before?

sl1m3r4l

Im also wondering if anyone knows if there's a way to specifically test my fuel pressure regulator without pulling off the intake manifold. As of now I'm not even sure if it is the pressure regulator so it would be nice to test it beforehand.

sl1m3r4l

Well of all things it turned out to be a p0157 code. I finally got a code reader and used it to clear the code. Now it's starting and running just fine. Hopefully the issue doesn't keep happening.

sl1m3r4l

So I'm currently experiencing an intermittent crank no start issue with my 1997 chevy express 1500. I'm very confused about what's going on.
I have spark, because it fires up when something flammable is sprayed down the air intake. Over the past week it has developed this condition and I've "fixed" it twice only for it to come right back after a couple days of running fine.
At first I thought it was an antitheft system issue but it doesn't seem to be that. Then I used a code scanner and found a p0157 code. I cleared the code and it started right up on Friday. It ran fine all day today until the afternoon when the issue came back. Now the code scanner is not finding any codes or pending codes. I did check my fuel pressure when I got it to start after clearing the code and it was definitely low. However I don't experience any symptoms of having low fuel pressure when I'm driving. It feels the same as it always has, no rough idle or stalling. It just won't fire up and then when it does it seems like nothing is wrong for a couple days.
Is it possible for a fuel pump to work so intermittently like this?
Tomorrow I plan on checking my ground connections and cleaning the one near my fuel pump. Does anyone else have any insight?
Thank you in advance for any input

sl1m3r4l

So my 1997 chevy express 1500 is just not getting fuel. Crank no start. I have ignition, fires right up when something flammable is sprayed down the air intake. I have a full tank of gas. My fuel pump relay is good and I can hear the pump priming. I also have sufficient fuel pressure. This issue has been intermittent for the past week, and when it starts it runs perfectly. However often it will just crank and crank and won't start all day. I've tried clearing codes, that worked one time but now isn't working. Something is just not letting my fuel injectors actually open. Any ideas what it could be? Maybe an ECM issue?

mountainmanjoe

Have you checked all your fuses/relays? Especially EFI

sl1m3r4l

Yes thanks for the reply. Checked them all a few times. No problems there.

mountainmanjoe

fuel injector testing