did you ever get around to fixing it?

 

nah we are gonna pull the opti this week need to put in an elec water pump in anyway

 

I'm having the same problem Now! (this post may seem pointless, but it was strategically placed to subscirbe me to this thread ). I'm thinking o2 sensors would trigger the check engine. I'm driving on old plugs and wires and yes when car is cold and i floor it LOOK OUT! once it warms up it and I punch it it starts hesitating/misfiring. Drives normal If I dont push it, but i know i'm getting bad gas mileage

I'm taking mine to one of my dad's shops so i'l post results.

 

Its your opti!! I'm 99% sure of it.

 

How do you test your opti? It seems like a lot of people are having this problem right now. I am going to get mine scanned first, but It would seem like I would be the last person to have an opti go...My car only has 25K miles, It has never been driven in the rain or snow, I only wash it a couple times a year (I Quick Detail it cuz it never really gets dirty). When I clean under my engine I always plastic baggie everything electrical, and I always steer clear of it.

 

what else could it be?

 

I'm not so sure it's the opti, cause I just changed mine last Saturday and it seemed to be fixed for a while until I took it to the track and it ran great cold, than just turned to crap when warm.

I also have new NGK Plugs, new ACDelco wires and coil and now new opti.

Next thing I'm going to try is the O2's, I guess will see.

 

when will you be changing these?

 

Hopefully within this week.

 

If someone gets to changing their O2's please post here. Im thinking it's the O2s. I get those symptoms every now and then. And I want to know if changing the O2's fixed it for someone...........

please help us

 

I have the same problem,its fine cold then closed loop it goes for a sh#t,but only intermitent.

I checked my vacuum at idle and its 19-20.

I used my laptop and freescan program,everything looks fine except my block learn memory on the right bank cycles down to 123.

I may have a header leak on that sides collector,which is before the 02.

I think I will change the fuel filter and check the FP before and after,and fix that leak.

 

I had that problem about a year ago, just as you guys are describing. But I seem to remember two other symptoms.
First was the backfiring / crackleing exhaust on deceleration.
Secondly was the miss at 5500 rpm's under load. Turned out to be a bad opti. I don't know if the wires were bad too but they got changed as well along with the plugs.
Hope that helps.