Tahoe fuel injection question

[gn69z28]

A friend wants to take the throttle body fuel injected engine out of his 1999 Tahoe and put in a engine with a carburetor and manual fuel pump. The question is will the in tank fuel pump still run with the fuel injection stuff unhooked. I suggested he remove the in tank pump but he doesn't want to do that. Thanks for any help.

[abc]

In the factory design, the fuel pump will not run with out a rpm signal after the initial prime function. He could easily put it on a toggle switch, where there is a will, there is a way.

[dfarr67]

Way too much psi..

[mt-engines]

The manual pump will pull through the electric pump.

But why would you toss out the efi? Better mileage, cold start etc..

He will need to hook up a TPS for it to shift proper

[rebelrouser]

A friend wants to take the throttle body fuel injected engine out of his 1999 Tahoe and put in a engine with a carburetor and manual fuel pump. The question is will the in tank fuel pump still run with the fuel injection stuff unhooked. I suggested he remove the in tank pump but he doesn't want to do that. Thanks for any help.

I have used the EFI pump with a carb, plumb a fuel pressure regulator, and as mentioned just trigger the relay with a toggle switch or rewire so it is Key on power to activate. Not sure what state you are in, but that vehicle is new enough that the emissions systems should not be tampered with. In my state Missouri, it will not pass safety inspection. And you would have a hard time selling it as well. I had a customer one time with a V-8 S-10, he got pulled over by a cop that was smart enough to know they never made a V-8 S-10, truck was impounded. Granted I see plenty of them on the road, it would just suck to run across that kind of cop.

[BillK]

Dont know why on earth you would want to do that ??? What a terrible step backwards. My 99 Tahoe has more power than I would have ever expected for a 350 in that big of a vehicle. It still runs almost as good as it did when new and is getting ready to turn 280K miles. And it still gets over 20mpg highway

That being said ........ I think he had better check to see what else will be affected by not having an rpm signal from the engine ? It might affect how the trans shifts etc etc. He would be better off finding the correct engine or putting a set of Vortec heads on his replacement engine and then using the existing fuel injection.

If he decides to proceed make sure he knows he will probably need a different flywheel depending on the year of the replacement engine.

[Racer71]

His ecm controls all trans functions, if it’s a half ton it will be a 4L60 trans. That will be his first issue with the bad idea. The pump in those makes 65psi running, he would need a bypass regulator to lower the pressure enough for a carb or go to a different in tank pump, another option would be a sump on the tank like we use on the diesel trucks. The block box type pcm those have have limited tuning ability but they can converted to the 411 pcm like what’s in the ls vehicles that’s highly tuneable.

[gn69z28]

This belongs to a friend. I don't know why he wants to do it either. I wouldn't do it if it were mine but he asked me to find out if it would work.