1997 3500 vortec issue

[Rusty c]

I have a 97 3500 with a 5.7 vortec the ignition switch was destroyed when I got it so I put a column in out of a 98 half ton also put in the dash and dash harness but the truck still won't start unless you dump fuel in it will I have to send in the pcm to get the security deleted or is there something else I can do also I forgot to mention that my scan tool will not connect with the pcm for live data I can only log in to it and get the codes and vin and such

 

[Nad_Yvalhosert]

If your assistant sprays starting fluid, will it stay running?
Have you checked fuel pressure?

 

[Rusty c]

I have not had a assistant but I can dump fuel in it and it will run a little bit until it runs out and I have tried a different fuel pump and no luck

 

[GoToGuy]

Have started with the basics. Sounds like a no fuel condition. " dump fuel runs" . So sounds like .... Why the new fuel pump? Fuel pump got power to the tank? Got power to relay? New pump is working? With new pump goes new filter installed correct flow. Thats what i would try from your descriptions.

 

[GoToGuy]

Ignition switch or key and tumbler?

 

[Schurkey]

I guess you'll be looking through copies of the '97 and '98 service manuals, to see what's different in the wiring harnesses.

And of course, checking for "ordinary" problems that might be preventing the ECM from communicating, or the fuel system from working properly.

 

[Rusty c]

Well it was the same thing with the old ignition and wiring the only difference is that the security light was on with the old stuff and it is off now

 

[Schurkey]

Well it was the same thing with the old ignition and wiring the only difference is that the security light was on with the old stuff and it is off now

What do you mean "the same thing with the old ignition and wiring"? Are you saying the scan tool wouldn't talk to the computer with the original parts installed? The engine wouldn't run?

You still haven't answered whether you changed the ignition switch or the ignition lock cylinder. Or both. I've never worked on a vehicle with a "security system", perhaps you need to get that service manual to see how it's supposed to work, and how to disable it.

What is the fuel pressure when cranking, and with the engine running on fuel you're supplying?

 

[Rusty c]

Yes it has never communicated with the scan tool other than getting the codes with either harness or ignition the original ignition was broken out and you had to use a screwdriver to turn it on so I put in the new column and dash harness

 

[tinfoil_hat]

Fuel pump relay?