Help Needed - Car Won't Start

[nebchevy]

If you are worried about the alterator take it to oreillys or autozone and have it tested. I swear it sounds like ani theft, my dodge work truck would start then die, then i would start it and would die...

[iHasCamaro]

Try your other key

[wyoming zl1]

i had a similar issue on a 2001 tahoe. It turned out to be a bad battery. It would start then die. I put a battery charger on it and it helped, but i ended up changing out the battery and solved problem.... i agree with an earlier post, you can take your batt and alt to any parts house and have them tested. most problems will show up.

[nebchevy]

Originally Posted by iHasCamaro

Try your other key

Yes this... there is anti theft stuff in your keys so try other one

[dragon22]

To completely rule out the anti theft system...put your key in the driver door and lock and unlock it a couple or three times. Then try starting it.

Another thing I ran into up here in the great white north...I went to a member's Tahoe to boost it and it did the exact same thing as yours, but they had not been working on it. I called one of the other drivers to help me get it out of the member's garage for the tow truck that was coming and he asked me if there was a garage door opener above the vehicle.

I looked up and sure enough there was. He told me to push it forward so it was outside the door and the truck would start. I'll be damned if he was right. First time and last time I ran into that! At this point, anything is worth a try.

[Moreno1]

Originally Posted by iHasCamaro

Try your other key

That's a good idea. When I went to start my car for the first time after a down period, It wouldn't start. Turn out the key was jack. It had gotten moisture inside. Use the other key and she started right up.

[572HP]

Thanks everyone for your input. I really appreciate the help and suggestions to try.

I tried closing the trunk, the hood, the windows, locking the car with the remote, unlocking a few times with the (other) key at the door lock. Tried to start the car with the second key, and same results. I locked the car, and tried remote starting the car, and it starts and stops in 1 second. I don't have a garage door opener above, it is mounted on the garage door wall, but I went ahead and unplugged it. No change. I haven't pushed it down off the lift and out of the garage, because I don't think I would be able to get it back up on there (4-post lift).

I only wonder about the generator a little bit. Yesterday I was able to remove the generator bracket, but I wasn't able to weasel the generator out without removing other stuff...namely the radiator hose. Before I cleaned the powder coat off the bracket where the bolts contact and the paint off the generator bolt brackets, I was getting a "Service Battery Charging System" message on the DIC. I'm not getting that any more. If I had some other type of clue that the generator is bad, I'd figure out a way to get it out. But because the computer isn't complaining, and I already fixed the ground issue with it, I'm not certain that is the cause. I can swap batteries easily just to see if the battery has any issues.

I checked for codes again, and nothing.

[Matt TuneTime]

I would be it's something you just did to the car , take belt off and start it if it stays running longer then the last time change alternator , if not you should double check you harness mods ....

[garcmol]

In the one second it's running, can you have someone start it and you put the red lead of a voltmeter on the output of the alternator? Run the black lead to where your alternator grounds and see if it's producing voltage? Same with the battery. The voltage should jump up on the battery as well while it's running.

You could leave the battery connected and pull the 5 and 20 fuse (fuse pull deal) and see if it resets the ECM. Don't know if that will screw with the tune as I've never fooled with that.

[garcmol]

Originally Posted by Matt TuneTime

I would be it's something you just did to the car , take belt off and start it if it stays running longer then the last time change alternator , if not you should double check you harness mods ....

Were the wires changed in the harness mod? Could a lower gauge wire cause a voltage jump between the wires causing a misfire? Any wiring changed to the cam position sensor? Fully seated?

[garcmol]

You know what? I typed this into bing search (engine runs for a second then shuts off).

Varying results but one person said the car sat for about a month, battery was weak. The only difference was he was getting an "immobile" light. I don't know if our cars even have something like that. Anyway, the solution was his key/car lost their relationship and the car would start, then shut off in a couple of seconds. Needed his keys recoded.

I know your work and it's meticulous. I doubt your mod is causing this after reading this.

[572HP]

Originally Posted by Matt TuneTime

I would be it's something you just did to the car , take belt off and start it if it stays running longer then the last time change alternator , if not you should double check you harness mods ....

I removed the belt, and same result. About 1 second of run time. The car starts immediately just like it always has. I have pinned-out all of the changes I made back to the ECM, but I'm getting ready to also check for any shorts between the wires. That will take a lot longer, but I think it is necessary at this point.

Originally Posted by garcmol

In the one second it's running, can you have someone start it and you put the red lead of a voltmeter on the output of the alternator? Run the black lead to where your alternator grounds and see if it's producing voltage? Same with the battery. The voltage should jump up on the battery as well while it's running.

You could leave the battery connected and pull the 5 and 20 fuse (fuse pull deal) and see if it resets the ECM. Don't know if that will screw with the tune as I've never fooled with that.

I'll try both...but that is a very quick 1 second! I did do the battery-pull, but I could try pulling fuse 5 and 20 also. Easy enough.

Originally Posted by garcmol

Were the wires changed in the harness mod? Could a lower gauge wire cause a voltage jump between the wires causing a misfire? Any wiring changed to the cam position sensor? Fully seated?

I used the same wire type and gauge where I extended the harnesses. None of the wiring to the cam position sensor was modified, or even touched for that matter, other than disconnecting and reconnecting. I believe the connector is seated. I no longer get the error code that I had when it was disconnected.

[572HP]

Originally Posted by garcmol

You know what? I typed this into bing search (engine runs for a second then shuts off).

Varying results but one person said the car sat for about a month, battery was weak. The only difference was he was getting an "immobile" light. I don't know if our cars even have something like that. Anyway, the solution was his key/car lost their relationship and the car would start, then shut off in a couple of seconds. Needed his keys recoded.

I know your work and it's meticulous. I doubt your mod is causing this after reading this.

Interesting. Maybe I'll call the dealer and see if that is something they can do without the car being brought in. That would be bad to have to take the car to the dealer.

[garcmol]

Well, do you still have that plastic tag that came on our keys with the code on it? I would think that and your VIN & registration would be sufficient.