Hey my car has been sputtering real bad the past week. It isnt throwing any codes but I am debating wether it is possibly the Opti or maybe the 02 sensors? I have open headers thats why I was thinking 02 sensors but wouldnt that throw a code? It ran fine for a month and a half with open headers now its doing this

 

Open headers will damage the o2's. Check for burned plug wires, and when's the last time you changed your plugs?

 

i will look at 02s tommorrow, how can you tell if they are bad? I change plugs last year, only put about 8,000miles on it since then. I will look over plug wires as well. But when i step on the gas it bogs then it gets up and goes so im leaning towards the 02 sensors

 

Well one easy way to tell is, does it do it while cool/cold? You can also unplug your MAF to check the o2's. Your PCM doesnt read your o2's untill the car is in closed loop.

 

hmm, it doesnt do it when its cold, once its warmed up it starts to run lke that, not sure what the prob is

 

then it's gotta be your o2's.

 

no, not necessarily. When I was having the issue with my opti, I definitely wouldn't have sputtering problems until it was warmed up. Then it kept getting worse, so the amount of time it took till I ran into the problem was smaller and smaller. Just, saying, it's not for sure.

 

mine was the same way... just a thought. check all the other things before the opti

 

My car did the exact same thing when it got warmed up after i put my headers on. This puzzled me cause it didnt bog down till it was warm, when it did i would be giving it gas and it would like sputter a bit and miss then accelerate like ****. I came to find I had some badly burnt plug wires, plus when I put my new plugs in during the header install one somehow got broke. So my car was running on like 6 or 7 cylinders half the time. I would do what Bawls says and unplug ur MAF. This will make it run bad compared to closed loop performance(normal running before your problems), but if it causes it to improve over what you were getting now, then your problem is the o2s. Then I would do a complete check of all ignition wires and plugs. If all that is good, then its your opti. Good luck

 

I am having this same problem. Runs like a champ for a day then the next day runs fine gets warm and it misses at idle every once and again then i slap the pedal and i get a boggy downshifting sound followed by a acceleration.

 

I'm surprised that you can actually run it with open headers without problems... I would think that oxygen from outside air would be read by the O2 sensors and that would cause the car to run rich as hell since the O2's would be so close to the end of the exhaust (sucking/blowing of exhaust).

 

it ran like a champ for the first month and a half. It is possible one of my wires couldhave got burnt, i still have yet to look over everything.

 

...when you say "open headers", do you mean no piping after the headers? Or just not muffler. My understanding of the term "open headers" refers to having exactly that... open headers. I would think that the exhaust would be sucking in air as it is expelling it also and that would cause the O2 to go crazy reading all the oxygen.