this is a 4.3 TBI in a 89 s10 and it idles erratically and will stall shortly after starting but if you floor the gas pedal it will only rev to about 2k and it is choking out and backfiring through the TB. I have replaced the whole ignition system and timing is dead on so it has to be a fuel issue.

What do you guys think it is before I start buying random things.

plugged catalytic converter? I am not sure otherwise...

no cat in it
this thing has me really confused it stopped backfiring and now you have to hold the pedal to get it to start but it will not rev up for nothing

Codes? Check for codes. CE light on?

Backfire is lean. Replace fuel filter to start. cheap.

Loan out a fuel pressure tester at parts store and check fuel pressure. check idle 12 lbs and then rev engine up and check at higher RPM again 12 lbs FP.. May be failing.

Did you replace the distributor? I had a 93 S10 do that, replaced the fuel pump, didn't fix it. ended up being the distributor reluctor was bad.

kind of sounds like a bad fuel pump. I have one that was working fine I just pulled out of my TBI if you want to buy it...I upgraded to a TPI pump.

remember to if you upgrade to a tpi pump the factory regulator will control it as well.

is that for me? I have an adjustable regulator on the car

It turned out to be the reluctor but the distributor was stuck in the engine and had to use a ball joint separator and a crowbar to get it out.

no the other guy. i know you have yours modded.

Ah okay. Just checkin'