wyldcdn

iTrader: (3)

Had a hesitation last night at the track (second time, first was day before after car idled for 15 min) I would punch it to take off act like plugs were loaded up from idling. Never happened til friday night at the track. nailed gas on green, hesitated and then took off. Tonight was going to cruise in, car started to buck and snort and act all screwy, like i had water in the tank. service light came on car ran fine, no problems. Stopped off at parts store , put in some fuel treatment, restarted car service light gone car ran fine. 5 mile later, it bucks and snorts all over again, pops through exhaust like a major misfire, light comes back on car runs fine. I got to car show, parked it for several hours. Fired right up, drove about 5 miles, misfire symtom comes back. Light comes on car runs smooth again. This happened everytime I'd shut car down and inspect it. I got to a friend whos a tech, while it still had the light on, the scanner showed no codes currently, history showed a 16. Car ran fine , stopped at gas station. Topped tank with new fresh fuel. Car ran like crap. Let it idle 5-10 min, light came on smoothed out drove home. I researched on like, found my answers. Is this optical module do this? run like crap then run fine after the codes/ engine check light comes on?

98pontiacfirehawk

Yes ,the defective optical sensor would cause your problem. You may want to chek out your opti harness while you are at it to see if you have any corrosion build up in the ends.

marine4life

that or it might be one of your O2 sensors not reading right or even bad.... chech tose too...

camar0corey

iTrader: (22)

most part stores can test your ICM, there is another possibility.

wyldcdn

iTrader: (3)

whats stumping me is why the car is running fine ...after the SES light comes on?

IronOutlaw

iTrader: (4)

My car did the exact same thing a while back after i put my headers in. It would read fine for about 5 minutes then backfire and chug for about ten, until the ses light came on. Turned out it was my oxygen sensors. Car stays in open loop until it gets warmed up (doesnt use oxygen sensors) then goes into closed loop (uses oxygen sensor readings) but then when it cant get good readings from the sensor it goes back into open loop.

Formula350

iTrader: (3)

Could it be the MAF bad guys? Wouldn't SES mode kick-back into Speed Density and use the MAP then, thus bypassing his problem? Then again SES does I think run in closed loop (or whatever "cold" loop is, I get them confused), which just bypasses pretty much every sensor lol

IronOutlaw

iTrader: (4)

When my oxygen sensors were bad i thought it was a MAF at first. I went and bought one for 150 dollars and it did the same thing... Oxygen sensors are cheaper id try them first.

Formula350

iTrader: (3)

Very true, but you could always unplug it while it's running good and see if any change happens. Or borrow a friend's lol

And I _H A T E D_ doing the passenger side O2 sensor -_-

wyldcdn

iTrader: (3)

swapped ICM today no changes. Have warranty on O2's will swap them tommorrow, AFTER I data scan it. Might as well learn from this. O2's make the most sense and not the opti. Computer isn't gonna be able to bypass firing order. cross fingers I'll keep getting this stuff right. Now heres something that crossed my mind today. I never even thought of why this all came about; BUT.....I am now using a QTP electirc cutout, and do drive with it open frequently. Would the extra flow, throw codes off? When I do the computer over, you can disable the O2's correct? Side effects?

IronOutlaw

iTrader: (4)

A cutout shouldnt throw codes like that. And you can only delete the o2 sensors behind the cats, not the ones in the manifolds. the car need them to run right.