Hi! I'm going crazy, hoping some kind soul can help.
2000 Blazer, 4wd....no modifications.

I recorded a video of the condition from start to idle:
Codes pulled:
P0302 (misfire #2)
P0442 (Evap small leak)
P0337/0339 (CKP high and low intermittent)
P0300 (misfire, random)
P0147 (o2 sensor, b1s3, after cat)
P0102 (MAF low input intermittent)
and some others related to lamps, wheel speed sensor.
Additionally, there was a sulfur smell a few times, now the exhaust smells of gas.

What I've done:
Replaced: plugs, wires, coil (only), wires from CKP connector up to where they join huge cable bundle.
cleaned: EGR valve, CKP sensor
Presumed: if engine runs, CKP is operating.

The rough running at low rpm has happened once before, about a month or so ago, but went away- both times coincided with heavy rain. it's not going away this time though, obviously haha.

SES flashes only after accelerating to over 20mph or so. Rough running did not go away at higher speed, but was almost not noticeable. An untrained person might consider it running "fine".

I can't pull codes anymore, no tester (did it at store, now I'm afraid to drive it), and I can't test fuel pressure.

I've purchased a FPR, and I'm ready to install it, and when the junkyard is open Tuesday I can go grab a damn spider if I need to.

I know it's a shot in the dark, but given this info, what would you clean or replace next? Please forgive me, I'm ridiculously broke right now after replacing my furnace and AC, and this truck is how I make money installing cable

 

As soon as you removed the ckp you messed up the timing. This could cause the missfire. crossfiring under the cap. You cant readjust it without a highend scanner. Moving the distributor is not how you adj. timing on these trucks

 

yeah, I was aware of that but....it's acting exactly the same as before. I'll throw a new one in and get GM to relearn it for me, but before that I'd really like to find something that makes a positive difference in its symptoms :/ just looking for a suggestion on what to try next that's within my capabilities (no expensive testing stuff) assuming I can replace pretty much anything. an educated wild guess, if you will. no liability, I'm not that kind of idiot (in a different kind lol).

 

I DO have a nice multimeter, and a test light. if that helps.

 

Feeling like an idiot right now. I thought the distributor was some kind of fancy one-piece deal you had to entirely replace. I never searched for "cap and rotor" cuz I guess I assumed a search for distributor would have yielded at least one or two results mentioning the cap and rotor. anyway....it was a bad cap and rotor.

 

dont feel bad, learning process, we all go through and thats what we`re here for