Ok so I just bought this 98 blazer 4.3L and I'm getting two p0304 codes and two type of o2 sensor codes (don't remember the codes but I will find out)... The engine is running really rough an sluggish but smooths out at high speed.. it feels like it want to just stall out but never does when I come to a stop, The rpm drops around or under 500. I also notice the oil gauge drops as well in this process then goes back to the middle...another weird thing I noticed is that the car doesn't accelerate on its own wen it's in drive or reverse, I actually have to push the gas pedal for it to even move. could this have to do with the transmission? I checked the transmission fluid an it's actually low and brown (smh) the last owner jus had it sittin. This I my new project I just need to kno where to start. tomorrow I'm going to add transmission fluid and treatment.

 

I would start with the o2 sensors. Dont worry about the oil pressure going up and down thats normal

 

Didn't mention this but the last owner had distributor, wires, and plugs changed. But I did notice the ignition coil was still old (most likely the same one from 1998) car sometimes hard to start. Was thinkin about that but u guys let me kno something first

I thought mayb going after the misfire first would be a good thing? Do o2 sensors cause engine misfires and idle problems?

 

Not sure, Had a bad o2 sensor and my truck ran like ****. Amazing what a new one will do

 

P0155
P0147
P0304

These are all the codes I'm getting
Anybody familiar wit these??

 

Looked through this section yet?