hello everyone im writing because i have a problem from long time ago and i would like to know if anyone have the same problem or if someone can help me with my problem.

i have pacesetter headers. and the problem is that when it was installed right after, i began to drive it (here comes the problem) when i first time drove it with the headers the car began to stall (i dont have another way to say it) like if you see it from the engine the car couldn't breath. and if you see it from the inside driving it feel like the car can't blow the fumes to the rear of the exhaust. when i was in complete stop (like waiting on the light) the cars RPM began to go up and down (stalling). i took it back to my mechanic.

my mechanic just disconnected a cable and it went off the stallingg but i lost response (i have been driving like this since then). so i ask if he can fix it. he did an extension to the cable. he says the cable is the sensor that is connected to header (heat or o2 sensor i dont remember).

i got back my response on the car but after a while the car began to do the same to stall and (plooh plooh plooh! i dont know how to do it lol) but this time was while i was cruising between 30to 40mph, and sometime do it when i am acelarating so i have to almost floor it so the stalling goes away. what i mean is that after they did the extension the car doesnt do the stalling as often as before bu still does it.

My mechanic says that the problem is in the header, because the hole for the sensor is in one of the tube of the header and is only reading that tube only and not the entire header (that what he told me)

So PLEASE help because i dont want to drive disconnected all the time and dont want to lose the response of the car.
I was thinking if is possible to drill a new hole like in the down pipe or somewhere near so the sensor can read the entire header the thing is, i got ceramic coated and i dont know if i can patch the old hole on the header.
i just an idea..

PLEASE help me. any comment or ideas are very welcome
Thank you very much.

I could be way off but here is a picture of the header I use on my ecotec..the sensor is located in the collector.. I've had no problems..with the senor at least

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which ecotech do you have? the 2.0L, 2.2L or 2.4L? on the 2.2L that is an O2 sensor, it sounds like your computer is confused as all hell because of the new location of the sensor (it uses the difference between the two O2 sensors, one up stream and one downstream for the cat to determine cat efficiency and control emmissions. this is why you loose response when the sensor is unpluged, the computer goes into what I call "limp-mode"). Try to find the plug from and aftermarket high-flow cat with two holes for the O2 sensor (one upstream and one downstream) to plug the old hole, and drill a new one at approximately the same location as on the stock manifold for the sensor.

johnathan probst wrote:which ecotech do you have? the 2.0L, 2.2L or 2.4L? on the 2.2L that is an O2 sensor, it sounds like your computer is confused as all hell because of the new location of the sensor (it uses the difference between the two O2 sensors, one up stream and one downstream for the cat to determine cat efficiency and control emmissions. this is why you loose response when the sensor is unpluged, the computer goes into what I call "limp-mode"). Try to find the plug from and aftermarket high-flow cat with two holes for the O2 sensor (one upstream and one downstream) to plug the old hole, and drill a new one at approximately the same location as on the stock manifold for the sensor.

He doesn't have an ECOTEC... He has a '97 z24... Which means he has a 2.4L TWIN CAM... it still has the 2 sensors but it shouldn't make a difference if the sensors are in a slightly lower position from stock... Tons of guys on here have had/have this header and they have had no issues so the location is not the problem.

Since you have to extend the upper O2 sensor wires is it possibly they are not connecting properly? The O2 sensor works on resistance and voltages... if the wires are not making a proper connection it could effect the readings it is sending to the computer... Also is it possible that the Mech accidentally rewired the O2 backwards when he extended it?



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Brandon G wrote:I could be way off but here is a picture of the header I use on my ecotec..the sensor is located in the collector.. I've had no problems..with the senor at least

you are right, I saw this post and just went with what I know (I think he mistakenly thought he had an ecotec). I also know that the closer the emission systems function to stock, the better. So the closer you can locate the sensor to its original position, the sloser it will function to the way it was intended. If it was originally located after the gasses from multiple cylinders combine, and now it is just collecting readings from the gasses from just one cylinder, it will be giving the computer conflicting readings and essentially "confusing" it. Again, I am just offering my personal knowledge.

Yeah, that makes sense with the getting a reading from a single VS multiple tubes...



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thank you very much everything
i forgot to mention something my engine lights are on for a loooong time the codes says O2 sensor 1 and 2. my mechanic change it and still come up.
he says the problem is in the computer.
my brother says also the same that i have to do something like a flush on the computer but i am not sure what i have to do.
thanks again

He probably means you need to reset your computer... just disconnect your battery for 5-10 minutes and then reconnect everything and give it a try...



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i already did it like couple times and still the same. it works because it reads the new stuff in the car but the car still do the same with the O2sensors, and still making the stall.

i unplugged my car for 2 minutes and the light didnt go off. i replaced the whole exhaust front to back and after the first drive the check engine came on and a week later it went off and then back on again and off and now its on for awhile. so should i unplug the batterie completly pos + neg - terminales for 10 minutes or more to reset the stupid computer? thanks

mine i did it but still the same it came up again and still makes the stall to me.
i have disconected the battery for hours and still came up.

try again both wires and didnt go off and i think it runs like crap too. yea more money to fix it then i got to spend.

i have try only one wire but i will see with two wires.

but my brothers says that i have to do something that the dealers only do it i think. something about clearing the entire computer, flushing or reseting something that can be done by the dealer. i dont even remember.

It kinda sounds like you still have a bad O2 sensor. Did the dealer just change it, still get the code, and decide it's the computer?

Try hooking up an AFR gauge to see if the sensor is giving proper output. He could have replaced a bad sensor with another bad sensor.

If the output looks good, check all the connections going back to the ECU.

my mechanic is the one that change the sensor. i will see if i can change it again.
he also says that is the computer and my brother is the one that says it can be fix in the dealer.

also i try to disconecting both cable of the battery and still.... same thing.