2000 LS2 cranks, won't start
 

I recently acquired a 2000 Saturn LS2, and I loved how she ran... Except she only ran for less than a day. I'd been driving down the road and slowly began losing horsepower--I put the accelerator to the floor, and I was barely chugging along. Pulled over, turned the vehicle off. It wouldn't start again. I had half a tank of gas, just filled. To my knowledge, there were no exisiting problems with the vehicle, but you're obviously taking a risk by buying person-to-person.

Gas gauge stopped working. Security light was always on, and it stayed on. I took it to a dealership (not where I bought it from), who said the engine computer was the problem. All fine and good; I replaced it and programmed it. Gas gauge started working, security light turned off, but the vehicle still won't start. I took the gas filter out to see if that was the issue... No. Poked a screwdriver in the Schrader valve... Gas sprayed everywhere.

Battery definitely isn't the issue, I had that tested and I've kept it charged. Checked everything I was told by family and friends--mass airflow sensor, throttle body sensor, fuse box. I don't know what else the problem could be, but I've been without a vehicle for a month.

The only other point I should make is that I've plugged an OBDII into the vehicle, and it runs zero codes.

I don't want to pay an arm and a leg by taking it to another GM dealership, and my go-to mechanic's shop has been closed for the past two months on account of the fact that his street is being torn up and fixed. Any ideas? I'm drawing nothing but blanks at this point.

​​​​​Ok, these are guesses and are to be used at your own financial risk.

1) the dealership did a repair and gave you back a non running vehicle? That's not a repair. That's a partial repair. Did you buy it as is or with a warranty?

2). Guessing they replaced the BCM. What does the security light do and now when you crank?

3). There's a tiny probability that the only thing that changed besides the BCM failing is that you got bad gas. You can try siphoning it out of the tank.

Before you do this, pull the fuel injector fuse, get some starting spray, remove the air intake ducting up to the throttle body. Spray a little bit of starting fluid into the throttle body maybe two or three seconds worth. Immediately crank the engine. Do this with a helper. If the engine fires then it may be bad fuel.

Number three costs you the cost of a can of starting fluid and some time.

Please report back w status of security light when cranking, starting fluid results.

Could be fuel supply issue as well but we'll check that a bit later

How many miles on the car? Did anyone check the catalytic converter? It sounds to me like it could be clogged. And, believe me, that'll definitely keep one from starting.

I should've noted that I took it to a dealership for a diagnostics test, not a repair. The engine computer I bought was third-party and replaced/programmed myself. However, what's been confusing to me is that the compatible computer is supposedly meant for an LW300. It does its job, or at least I'd like to assume; when I turned the vehicle on and off several times this morning, the gas gauge would work but the security light would be on. Then other times, the gas gauge wouldn't work but the security light would be off. I'm assuming the computer is doing *something* right, because I've been hearing miscellaneous clicks and hums beneath the hood, which it hadn't been doing with the bad computer.

I'll be trying number three shortly. Thank you much.

115k on the car. I believe a friend of mine checked the catalytic converter, but I can do some sleuthing. I'll let you know the verdict on that.

Security light and gas gauge are both controlled by BCM. Do a passlock relearn. No it won't help the gas gauge but it may help you to figure out if security is an issue.

If BCM does not think it got the right "password" from ign switch, it will never tell the PCM to stop inhibiting the injectors, so you can crank all you want but you never have fuel.

Reflash your PCM (correct part number) and reflash the BCM or reflash a junkyard one (correct part number) .to match your vin. Just take a picture of the mileage before you start.

Really sounds like a BCM issue now that you have provided more information.

my 200 ls2 doesn't want to give the code either. unable to connect. My problem was a bad battery . jumped started i, was running ecellent,t took it home, nest day crank no start.. I then disconnected the battery cables and touched th + and - cables for two minutes. reattached them it started right away runs fine. $ days later same thing had to disconnect the battery cables again and touch them together.

My gas guage would not work when key on on position. could not get scanned "unable to connect"
take off the battery cables , - cable first then the + take a wire connect them together for 2 min , reattach them and see if car starts.
good luck

I don't think Hannah is coming back, Casey. It's been over 5 months since her last post. But thank you for your suggestion. It might help someone else that runs into this situation.