Ok I have a 96 camaro 383 and cam. I was driving to day all was good intell I got a real bad misfire in the lower rpm cruising so I punched it it goes away. Back to cruising speed and it comes back aging I haven't checked code but I'm sure it's got a misfire code now I'm stumped it's smells like it's running rich when it dose it. I'm going to pull plugs tommrow and check codes. Any help would be great I'm thinking the opit is going bad but I'm not sure. What do you guys think?

 

Also cars was running fine all week till now

 

I would check for codes, How old is the Opti spark?

 

Opti from what I guess and looks like it was replaced once but not sure how old .What do you think about a map sensor cause of it happen at light acceleration or coolant temp could be bad and throwing it around from closed to open loop ect. I guess when I pull codes I we'll know more

 

Light load misses are the almost as bad to track down as rough Idle. The reason is because they can be cause almost anything in the fuel injection or the ignition systems.
Step one in a shop would be to figure out if it is a Lean miss or a Spark miss. That would be done with a scope. Hopefully codes will give you a clue.


FYI there are a lot of cheap Opti's out there. 1-2 year life is not uncommon on those although some last longer.

 

Found at bank 2 o2 sensor is dead

 

Might want to pull those plugs, It is pretty common when you find a dead O2 sensor like that there is a reason it is dead. It could be anything from a small vacuum leak or a dirty plug to one cylinder burning oil or coolant. If it is dead for a reason most likely one or two plugs are different from the rest on that side.

 

We'll when I got the car the fuel press reg was bad along with the mass air flow. So I'm guessing that and the fact that the old owner dump two bottles of fuel injector cleaner in it didn't help I've been going throw the car for weeks replace and fixing stuff. That the old owner had no idea what he was doing as for plugs I pulled all of them and cleaned them when I got the car. Since the fixes stated above I took um back out and they seem okay no oil deposits or any hints of a coolant leak internal oil looks good not milky like coolant is mixing with oil. However I do have a oil leak some where in the back not sure if it's a intake leak or rear main seal. Ect. I'm still trying to narrow it down

 

Well the fuel reg and the MAF sensor would explain the dead O2 sensor. Could be that the dead O2 senor replacement may fix the lean running. Lean will cause a light load miss.

 

Since I put the new o2 in all is we'll aging now I'm trying to find that oil leak. I was under it a bit today changing the diff gasket and oil. Along with the trans. So I cleaned it up pretty good so I can see where it's leaking at. Like I said it ether the rear main which I kinda dout oil dip stick tube or the intake I stuck my hand behind the intake who ever rtv it sucked at life and I had some oil on my hand. So I'm thinking it's coming from there but I'm not ruling out the dip stick tube ether it's not a bad leak but over time the trans and under body gets coverd