My 1996 Chevy Tahoe wont start unless you put gas into the throttle body

Incorrect Crankshaft position and valve timing.

It has an interference engine, so the piston came up and hit the valves and jammed with piston. You now have bent valves.

Is my 1999 Tahoe 5.7 L an interference engine or not?

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May 15, 2018 · 1 answer
Hello, it is an interference engine.

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Check the ecm main relay swap it out with the horn relay and see if it starts the Ecm controls the fuel pump prime and when it runs if it not working correctly it won't run the pump

it will be a good idea to clean injector. It's a good thinking to clean throttle body......never forget for good combustion you need AIR,good FUEL,and good spark
when you need to crack up the throttle plate to start means throttle body dirty and IAC valve dirty or not working properly
hope it helps

Computer showing any codes? Could be a bad regulator or a leak in the system allowing air in and fuel to flow back to the gas tank.

The Adjustment for the proper air flow at closed plate,
is set & sealed,do not change it.

I think you got a spring somehow in wrong

Why did you take off the tacm (motor)?

I'm following another issue like this on a 1996 Jimmy.
This engine requires 60psi or more fuel pressure to run.
You need to have someone check the fuel pressure at the rail- throttle body with a gauge.

Check the fuel pressure. Even if it's running it may not be producing pressure. See if you can keep it running on starting fluid or carbuerator cleaner. If so replace the pump.

fuel pump or fuel pressure regulator. When you turn the key do you hear fuel pump run? If not odds are the pump is bad.

Sounds like you have to much gas going thru the throttle body. When you put your foot on the gas it opens the airway and lets air and no gas. The black smoke is unburned gas. Replace the throttle body and you should be good to go. It could be the fuel sensor also, telling the pump the wrong info.

you could be having a bad pressure regulator ,it seems to be wasted now.