I am getting so frustrated with my suburban. 2001 suburban 1500 2wd over 200k miles. A little history (husband is luckily not able to work on vehicles anymore!): the drive shaft had new u joints put on (by my husband) but I told him the yolk and drive shaft end needed replaced due to the damage from the first exploded u joint. He said it would be fine. HAH! A few months later the yolk and u joint exploded on the highway, the drive shaft barely held on long enough to limp home, and I ordered a full replacement for less than the cost of repair in my area. When the drive shaft popped it smacked the exhaust pipe on the passenger side busting the seam where the pipe is held to the frame and he attempted to weld it twice. I told him it needed to be pulled out and done properly. He didn't like that plan. I ordered the automotive exhaust pipe jb weld paste and he put that on after the second weld job held up but still had exhaust leaking. Before the issue with the drive shaft, my suburban was running fine. No problems with idle or throttle.
Now to my current ongoing issue... I have replaced the MAF sensor, all 4 O2 sensors, IACV and TPS twice, cleaned the throttle body thoroughly twice, checked the throttle cable, replaced the spark plugs, checked wires everywhere for damage, and still my truck is doing this weird sporadic throttle/idle thing. Sitting at a light and let off the break and she tries to fly off with the rpms jumping to 5k and will coast on her own at 50mph, difficult to slow down due to the engine wanting to race. Sitting in park the engine will rev up and down between 300 and 5k, but not always because sometimes she idles so low that the ac blows hot and the ac clutch won't engage without a little pressure on the gas pedal. I ordered a fuel filter and fuel pump and chewed my husband's butt for always "getting a few more drops" when we get gas to get an even dollar amount. Just read the codes again and I got P0140, P0160 (both rear O2 sensors so I'm assuming still exhaust leaking somewhere) and P0332 (knock sensor 2). After replacing the O2 sensors, she's running better, they were so corroded that it took me all day to get them out, 1 was cross threaded, and honestly I'm surprised the truck was even running with how bad they were. She isn't trying to take off as much but still doing the reving up and down in park. I really hope the fuel pump and filter fix this issue but what else am I missing??? What can I do to find the exhaust leak? I have disconnected the battery and made sure all residual power was drained to do a total reset/relearn protocol following the directions I found on several of the threads here, and it still isn't running right. I love this truck and am enjoying working on it, but if i can't get this issue fixed then I'll have to get rid of it.

 

where on earth did you get 2021 or silverado???? It clearly says 2001 suburban.