Worthwhile to convert from TBI to Quadrajet?

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Matt69olds

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Look for a vacuum leak at the throttle body.

Remove the IAC valve, throughly clean the IAC bore and the plunger on the end of the valve. It may be caked full of carbon.

The biggest flaw with TBI engines is people screwing around with them when they have no clue what they are doing.
 

YakkoWarner

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Look for a vacuum leak at the throttle body.

Remove the IAC valve, throughly clean the IAC bore and the plunger on the end of the valve. It may be caked full of carbon.

The biggest flaw with TBI engines is people screwing around with them when they have no clue what they are doing.

I need to do this with mine (clean the IAC that is, already did enough screwing around trying to understand how it works!). How hard is it to remove and how likely is it to break?
 

Matt69olds

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I think takes a 1 1/8 inch wrench to remove, it’s easy. Unplug the harness, break it loose and it comes right out. Spray a bunch of carb cleaner in the bore, soak a rag with carb cleaner and wipe off the IAC plunger, thread it back in.

This is somewhat routine maintenance that’s easy to overlook. If the bore is clogged and restricted with carbon, the plunger can’t control idle airflow.
 

Grit dog

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Thank you all for your input on this. I'll most likely just fix the issues with the tbi and see how it does. I'll mostly only be towing a car trailer with another truck on it, so the 350 should do fine. And yes, the fuel economy would be nice. This will likely replace my '04 Silverado as my daily driver. It may actually use less fuel!
I'll start with the idle control valve and search for vacuum leaks. Having sat so much, it's likely I'll be replacing a few vacuum lines anyway. The previous owner had replaced the fuel pump and brake master and vacuum booster.
It would seem 100% counterproductive to chit can a super low mile good running (according to you) stock engine stock everything TBI.
Especially if you’re keeping it stock and now want to dd it.
 

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