Your key Code here is 41: HEGO sensor circuit indicates system lean. The computer is dumping in fuel to compensate. The EGR Code 33 is not going to trigger a lean problem. Did you remove any of the air injection (thermactor) tubing and/or vacuum operated valves? If you so did you plug the ports on the back of the heads?

Is the idle RPM higher than normal? An indication of a vacuum leak.

At this point I would pull out the computer (PCM) then open it up for inspection. Given the increasing rate of leaking capacitors it's became a standard troubleshooting procedure these days.

 

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The air injection tube was disconnected from the exhaust the pipe it was connected to was replaced. I did find an exhaust leak in front of the O2 i i patched it.

And it idles at around 1300 in park and it surges
​​​​​in drive it idles at 1000 and will sometimes slowly drop to around 800.

I will check out the pcm later.

 

some are easy to see, others a little harder

pic courtesy subford

pic courtesy subford

 

There is a tube that connects to the back of the heads and other tubing/valves that make up the air injection system. Any of those can contribute to a vacuum leak/lean code.

That seems a little high to me. Add in a surging idle, lean code are pointing to a vacuum leak.

Good idea.

 

Where can vacuum leaks occur on this truck? Ive searched and searched, used smoke, and carb cleaner and i i cannot find it.

 

Everywhere....brittle vacuum lines, rusted vacuum reservoir, leaking power brake booster, plenum gasket, throttle body gasket, worn throttle body bore/shaft, intake gaskets. I have found the carb spray method to find vacuum leaks to be very unreliable on these EFI vehicles. Too many nooks and crannies.

Another quick test to see if you have a vacuum leak is to start the engine then remove the connector to the IAC. If the idle RPM drops to 4-500 RPM or the engine stalls the vacuum theory is busted. If the idle RPM remains high then you need to see if someone has jacked with the throttle stop screw, if not you have a vacuum leak or a chance the IAC is stuck or worn allowing too much idle airflow.

One of my favorite methods to isolate where the vacuum leak(s) may hide is disconnect all of the vacuum lines at the port and back of the intake. Cap all of them except for one to the MAP sensor, another for the fuel pressure regulator. Fire up the engine, see if the idle RPM returns to normal value. If not the leak(s) are on the engine. If it does, the leak(s) are external.

It's all a process of elimination. No need for a bunch of parts, just start narrowing down the causes methodically.

 

LEAKING BRAKE BOOSTER, what would the brakes feel like if it was leaking, my breaks feel very spongy. Like i have to mash it in a good bit before they work its like the booster lags or something and when im at a stop the brake peddle continies to go downward, if i hold it in place then thr brakes slowly release snd the truck moves forward.

 

Classic symptom of a failed master cylinder leaking internally.

 

Is that where the keaks comin from?

 

Do you hear any hissing?

 

without driving it, remove your brake booster vacuum line from vacuum tree on intake and plug the vacuum tree where brake booster line was, and see if your idle comes down diaphragm could be bad in brake booster, giving your hi idle, and look underneath behind each wheel to see if it looks shiny/wet(brake fluid), will tell you if its a wheel cylinder(rear) or caliper(front) gone bad, have you had to add brake fluid to brake reservoir, lately

 

When i presd it it goes shhhhh till its ill the way down then it stops

 

No leak. Reservoir level hasnt changed from the last time i i filled it. Well it went down like a tad but im talkin not even a centimeter

 

Took the line off and plugged. No difference in idle

 

I unplugged my idle control valve, it goes down to just above 1000rpm and stays.