OK first off this is a 1993 firebird formula the only mods are magnaflow catback and eBay CAI. the problem is when the car fully warms up at around 180ish the car will run like crap and sputter and surge. it never did this befor untill i instaled my CAI i just replaced the opti. new fuel pump new wires and plugs. on first cold start up the car will run fine. this only happens when it is warmed up can somone please help me out here

 

does the car run well or crappy at wot?

 

well when its still cold the car runs fine nothing wrong at all but when its warmed up it wont let me run WOT it surges and spits and doesnt shift

 

map sensor check it out...its bolted to the front of the intake manifold...had the same problem... if thats not the problem I would start checking your o2 sensors...

 

or could be something simple like spark plugs and wires?? opti taking a dump? fuel pump...beats me I would honestly have to drive the car...

 

any codes?

 

i replaced both o2's recently fuel pump is brand new and the opti is less then 4000 miles old but how would i check if its the map sensor would i have to just replace it..?

 

just replace it its not expensive.. or just try it on and if it makes no difference return it.. check your ICM..did you bolt the icm directly to the head by any chance when putting everything back on after the opti install? Im asking because i accidentally did! lol.. car ran like **** when it warmed up.. go get one from a j-yard.. not expensive at all

 

yeah it could be an ignition heat soak issue. Try the icm cooling mod. If it runs bad at wot also then its likely not the o2 sensors.

 

try replacing the coil wire.

 

could be bad fuel injectors, probably not but a possibility. When cold it is not very noticeable, but when warmed up you can tell for sure

 

I just got done with this same problem and mine happened to be the plugs and wires, my coil wire was rotted onto the opti.

 

untrue - WOT could be an o2 sensor had this happen to me and people on here tell me it wasn't got some used o2s and tried them and bam went away.

 

That's why I said it is "likely" not. Yes in some cases it can affect wot, but usually it will not. It depends on how the o2 sensor fails. If it gets stuck on a lean value then the computer will dump in way too much fuel at wot, otherwise it will have no effect.

 

i just realized there is a hose that is not conected that used to go onto the old intake that runs to the round thing then goes to the exaust manifolds i think its part of the egr could this be the problem?

 

bump really need help

 

did u put that intake hose back on?got a pic of the engine bay?

 

Wow, your only in Canton! I am about 25 miles from Edon, OH and I drive through there going to Michigan Speedway. Maybe I can help you out. This could be an EGR issue but not likely (it closes at WOT). I am going to say check your fuel pressure. I wonder if your car isn't getting enough pressure because I have seen it before. Also, when you check it, unplug the regulator's vacuum feed and tell us what you get. I am leaning toward the O2's and the ICM theories too.

 

Thats cool man maybe we could meet up sometime your out this way.

ok so what ive come too is that the car at cold start up runs fine may have a slight misfire at 1400 rpms but nothing to major but when the car gets up to running temp 190* and has been running for about 25 mins the car starts to surge and sputter. in park the rpms will bounce around and in gear the car will surge forward like the car has some massive cam. from a deap stop the car will surge extremly hard and barley move forward with gas. at wot the car will bog out like im hitting a rev limiter or the trans is sliping. In order to get the car out of first gear you must take your foot off the gas. I really need help fast please anyone. Im willing to pay ahhaha

 

honestly is starting to sound like a plugged cat. You guys don't have emissions up there do ya? I'd just gut the thing.