Well this is weird, and im sure its been covered, but I searched and couldnt find anything....I had a CEL on for bad o2 sensor, so I bought a o2 and the CEL went off. When the CEL was on it would sometimes die alot, but sometimes not alot, so when the CEL went off I thought it was fixed becasue I kept pushing the clutch in trying to make it die but it wouldnt. Today I was driving around and it would still sometimes die. I have no CEL. What could it be?

 

Your computer probably has a lot of trim in it still from chasing the faulty O2 sensor signal. Reset ECU by disconnecting one battery cable for 30 seconds. Then reconnect cable. Now the ECU will start from its default numbers.

 

Or you can pull the 30 amp back up fuse in your fuse box for the same amount of time.