93 Chevy 454 Cat Delete 

You should get a fuel pressure gauge before you go changing a bunch of parts.

Heat shrink is great for repairing vacuum hose

Need a heated o2 sensor with the cat delete. The better flow causes the sensor to get too cold

These have a habit of egr being an issue, also once warm is always a good idea to check ignition control module

Nathan, I know I wrote a book with this post, but read it. The TBI engines are so simple to diagnose and not fire the parts cannon at it. First before anything we need to see if its a sensor. Once the engine is warm it puts the ECM into closed loop, and now its getting info from the sensors to adjust the fuel and spark. You can unplug the coolant sensor (may be 2 one for ECM one for gauge) that will keep the ECM in open loop, wait till it gets hot and if it runs great hot and in open loop then we can start to diagnose sensors. It could also be the spark module in the distributor. It may be worth driving it to an auto parts store that has an ignition module tester, just pull it out in the parking lot and take it in. They tend to work good cold and once they get some heat from the engine they start messing up. If you can mount your go pro under the hood take and remove the entire air cleaner and spacer. Point camera to the TBI and drive. You can see the fuel spray into the TBI and possibly help figure out spark or fuel issue.

Those older TBI throttle bodies have fuel lines that run along the back of the engine and when you run the engine it heats up those fuel lines and you get vapor lock so unbolting the bracket and putting some silicone hose around those fuel lines can help stop that problem

Fuel Pressure regulator is on the rear of the TBI unit. You'll see it connected to the injector cradle.

I would definitely lift front of bed or drop tank and check all electrical connections for the fuel pump

I experienced power loss on my 88. Replace all sensors, replaced entire ignition system, eve cut the cat...cutting the cat i dont like it...the fumes are outrageous lol, i walk in the house snelling like exhaust smoke. Ended up being my spark plugs and wires that i just replaced 1.5yrs ago.

That one looks like it'd be pretty tough to gut I gutted the one in my 2nd gen dodge while it was still attached to the truck just cut the exhaust off behind it, then started the truck and blew it all out after running a drill through several times, and reattached the exhaust with a clamp. Great video

The coil pack is shorting out when they warm up. If it has two coils, one will reduce power to both coils.

It's not an EGR valve It's not an O2 sensor it doesn't have that kind of authority. If you think it is lacking fuel, find a way to give it extra fuel while you are driving and see if that remedies it, propane Works real well. The way it surges on wide-open throttle I would be looking seriously at the distributor pick-up inside the distributor. The rhythm of the that surge is Not an Accident there's a reason. Try propane enrichment first, if that works back-trace and find what's wrong with the supply system.

Yeah I never seen a cat that far back either. But I would still look at that fuel pump and pressure on it. And when you take it down the driveway and it starts acting up take your rubber mallet with you and then hit the tank if it snaps out of it right away that's your problem. Fuel pump

Hmmm , might be the ignition module.. or possibly the computer.. seeing it’s old capacitors go bad. Maybe get a can of duster spray for computers from the dollar store.. and turn it upside down.. and spray the model. It will come out as a liquid and freeze.. cool it quickly..

Could be a dirtyaf sensor

keep it up nathan-you will fix it/thanks much

I had a issues very similar to that and it ended up needing a new throttle body

Good job

Common GM cat they call it a Bead

Take it to auto parts store put obd scanner on it!

its an old pellet style converter...usually fail when the fill plug rots out and blows out the pellets

I'm guessing your check engine bulb is burnt out! 😅

Thanks

There be gold in those converters!

Probably o2 sensor. I would guess the open/close loop isnt working correctly (due to bad o2) when the truck warms up, causing fuel trims to be weird.

that looks like a resonator

Catalytic convertors are worth MONEY $$$

Temp sensor

Platinum

😏 sounds v8 no cat

Here is a thought it started to act up after you hooked up those wires that you don't know where they go so it might be the electric choke I do believe it has one just trying to help 😊

Meow 😸 sell it at the scrap yard.. just research what it’s worth.. it might buy some welding wire or shielding gas

Change EGR with that much mileage!

do the throttle positioning sensor first then the o2

I don't think that was the catalytic converter, those are the first thing in the exhaust system. If your engine has an upstream and downstream O2 sensor the catalytic converter is between those two. To me that seems like a muffler. The real cat what you wanted to remove was probably other thing what you left there, and it's still in the exhaust system.