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1992 tahoe only starts if you put fuel in the tbi

the fuel pump works and it has new injectors

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any error codes? How do you know that the fuel pump works? Did this just start? Anything happened to it before? What engine is it....more info is needed to even closely give you an idea about such a broad problem.

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it has a new fuel pump and its a 350. whats an error code?

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That is usually displayed when you hook it up to an analyzer (done for free at places like Autozone etc;-) Does your service engine light come on? Why Did you get get a new fuel pump? Did you check the wiring at your fuel pump to see if you get power to it?

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like 4 months ago the fuel pump went out so i bought a new one put it on and it ran fine then i stopped using it for about 3 months and now it only starts if you put fuel in the tbi and no the engine light doesnt come on

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Not enough power to fuel pump. The injection system is very sensitive to fuel pressure and even 1 psi can stop it from starting. Guarantee it's a dead cell in the battery. Bet on it.

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Black Friday
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Oskar this is what i got from the manual. Again this could just be a start since it is a broad error.

Test the fuel pump control unit.

-Disconnect fuel module

- with test light and ignition "On", probe connector "C" to ground Circuit it OK if light is ON. There is an open if light is " OFF.

- Probe Connector terminal "C" to "D" with test light. Circuit is OK if light is "ON". There is an open in the ground circuit if light is "OFF"

- Ignition "OFF", probel connector terminals "A"to "D" with test light. Ignition "ON" test light should illuminate for two seconds. There is an open in the circuit if the light is "OFF".

- Replace fuel module if there is no twenty second fuel pump operation.

See the attached image for the location of the module.

When the key is first turned ON, without the engine running the ECM will turn the fuel pump relay ON for two seconds. This builds up fuel pressure to normal operating pressure. If the engine is not started within two seconds, teh ECM will shut the fuel pump OFF and wait until ignition reference pulses are present. The ECM contiunues to power the fuel pump during engine operation. If the fuel pump relay fails, it is backed up by the oil pressure switch, witch continues to operate the fuel pump as long as oil pressure remains above 28 kPa.

So check your fuel pump relay. The location is on the attached image.

Good luck for now and let us know how it is going....

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i have a 99 with the same problem. Pressure gauge on the fuel reads roughly 51-52. Also have replaced the fuel pump twice now(yes they were bad). The original went out after 10 years and the second...Napa brand...went out driving down the road after 6 months. The check engine light is not on nor does it show any trouble codes. I am open to suggestions at this point. Tahoe is a 4x4 two door with the 350 engine.

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go to accuratediesel.com. He has an altered EMC which can be installed in 10 min. He also posts detail trouble guild.

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I can only find the diesel parts. Any direct link you can post?

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