Ok heres what happened!!! When i installed the motor i didnt have the correct injectors in it and it was lean bad. So i got the right ones and a retune and it ran fine for a while, then started acting funny starting up and then got to where it didnt run right until you floored it. So i called up at F.A.S.T. and talked to Tony, he told me to unplug them and see if it got better so i did and it did. Well since it was running better i have never put any back in it. My question is: Is running without O2's hurting the performance of my motor? And which ones do i need to get?

 

You are flying without a parachute if you don't tune for open loop. Most people's Open Loop F/A table has a value of 1 all the way down to 100kpa. 14.7/1 is 14.7. So unless you are in PE, it will be commanding 14.7. Sounds great, but ask yourself this...what sensor tells the computer your AFR? Yeah so if for some reason you are ACTUALLY going lean, you will have no "parachute" to correct the action.

Open Loop is safe if you are tuned for it and have a wideband to monitor possible issues.

 

well thats what i dont understand!!! When WOT its like 12.4 - 12.6 how is it being commanded here?? but idle it jumps around alot all the way to like 15 sometimes

 

Just a calculation. PE is a commanded value, If your tune was spot on, to get 12.6 you'd have a value of 1.167 in the PE table. Your tune is already tuned for 14.7 so the PCM just makes a calculation change to get to the 12.6. WOW, does that make sense...I think I confused myself.

 

lol, muscle relaxers are fuggin with me...divide 14.7 by 1.167. That's all your PCM is doing. (plus a larger calculation to the injectors, but that's another story)

 

The idle deal is just weird VE/MAF cells. Sense your are open loop you are not offering correction. When in closed loop the pcm will correct and bring back to stoich.

 

yea i've seen tables of the different values but i dont tune it so i dont know whats done to it. im just wondering if the tune could be better with the o2's or probably not change anything.

 

thats also something else i noticed when they were bad and still hooked up, it would always be in closed loop, now i guess it still is.

 

The PCM may be commanding closed loop, but with no O2 you are not in closed loop because there are no sensors to give feed back to the PCM.

 

so i am most likely leaving some ET on the table. ok so now which part # am i going to need to get ive heard NGK is better than Bosch