Do Performance chips bypass the O2 sensor?
07-08-2005, 12:49 AM
#1
Racer
Thread Starter
Join Date: Oct 2004
Posts: 442
Likes: 0
Received 0 Likes
on
0 Posts
Do Performance chips bypass the O2 sensor?
I was wondering because my O2 sensor is still origanal and I have a autothority Performance chip in my 86' N/A. So before I spend 60 bucks for a sensor and waste a bunch of time replacing it I would like to know. Thanks
07-08-2005, 01:48 AM
#3
Lazer Beam Shooter
Rennlist Member
Rennlist Member
I know the FRwilk chip ignores the 02 Sensor. I would think the Autothority does the same as most chips force a mixture instead of adjusting based on the sensor. This is why most chips make you fail emissions. I could be wrong though. Anybody else?
so that doesent matter.
07-08-2005, 02:02 AM
#6
Lazer Beam Shooter
Rennlist Member
Rennlist Member
I dont think it should be too hard on the cat, because youre not running horribly rich or anything. Youre running just right enough to get some extra power. Running too rich i think you would loose power and destroy the cat.
07-08-2005, 02:41 AM
#7
Race Car
In alberta, eh? Don't suppose you're a Calgarian?
It's neat to see other Albertan's.
I have some aftermarket chips in mine, unknown brand, but they run so rich that my cat glows red at night. Definately not good. Mine ignore the O2 sensor. I could be wrong, but I thought almost all performance chips did, since the O2 sensor was there to help encourage the formation of the least byproducts during combustion. Which would of course have a negative effect on how much horsepower you make. I don't know of any good ways to check without an exhaust sniffer.
It's neat to see other Albertan's.
I have some aftermarket chips in mine, unknown brand, but they run so rich that my cat glows red at night. Definately not good. Mine ignore the O2 sensor. I could be wrong, but I thought almost all performance chips did, since the O2 sensor was there to help encourage the formation of the least byproducts during combustion. Which would of course have a negative effect on how much horsepower you make. I don't know of any good ways to check without an exhaust sniffer.
Trending Topics
07-08-2005, 02:50 AM
#8
Racer
Thread Starter
Join Date: Oct 2004
Posts: 442
Likes: 0
Received 0 Likes
on
0 Posts
no delburne near red deer population 500 my N/A is almost the fastest car in town other than a dodge viper SRT-10. You thought SUV's were getting bad down there in the states theres only 25 cars in town every thing else is a truck, SUV or Van.
07-08-2005, 01:58 PM
#9
Three Wheelin'
Most 951 chips use the O2 sensor for idle and part throttle fuel mixture. My Autothority chips passed emmisions testing, once the PO found out that the O2 sensor had been deliberately unplugged so that the cips couldn't use the sensor. The same chips were horribly rich under full throttle. GURU chips also use the O2 sensor for idle/part throttle, and pass emmisions testing no problem. Might be different on the NA cars though (FRWilk.)
07-08-2005, 02:13 PM
#10
Captain Obvious
Super User
Super User
To clear things up a little:
The only time aftermarket chips change anything is during wide open throttle operation. They do not change anything during partial throttle conditions. Its’ too difficult to change parameters cause all the sensor readings effect the fuel and timing curves when the throttle is only partially open. The system is in open loop at this time and makes all the change requirements from all the sensor data collected. Once the throttle is wide open (100%) the system goes into close loop and disregards all the readings from most of the sensors. I think the MAF and maybe the O2 are the only ones that influence the fuel and timing at this time. The aftermarket chips only makes changes to the closed loop matrices.
You still should change your O2 to get accurate reading during partial throttle operation. O2 sensors get slow and inaccurate as they age. If yours is old, changing it should really wake up your engine.
I hope this helps!
The only time aftermarket chips change anything is during wide open throttle operation. They do not change anything during partial throttle conditions. Its’ too difficult to change parameters cause all the sensor readings effect the fuel and timing curves when the throttle is only partially open. The system is in open loop at this time and makes all the change requirements from all the sensor data collected. Once the throttle is wide open (100%) the system goes into close loop and disregards all the readings from most of the sensors. I think the MAF and maybe the O2 are the only ones that influence the fuel and timing at this time. The aftermarket chips only makes changes to the closed loop matrices.
You still should change your O2 to get accurate reading during partial throttle operation. O2 sensors get slow and inaccurate as they age. If yours is old, changing it should really wake up your engine.
I hope this helps!
07-08-2005, 07:01 PM
#11
Race Car
Delburne... Been there once, don't remember much of it.
Haha, a viper in town. There are only a couple in Calgary, but in a town of 500, there is both a 944 and a viper.
Haha, a viper in town. There are only a couple in Calgary, but in a town of 500, there is both a 944 and a viper.
07-08-2005, 11:06 PM
#12
Instructor
Mine has an A.P.E. chip in it and it does ignore the O2 sensor. I can sometimes see the unburnt fuel as a fog in the back at WOT. I only punch it on the track though.
07-09-2005, 12:22 AM
#13
Racer
Join Date: Mar 2003
Location: Bellevue, Washington
Posts: 418
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Waterguy
Most 951 chips use the O2 sensor for idle and part throttle fuel mixture. My Autothority chips passed emmisions testing, once the PO found out that the O2 sensor had been deliberately unplugged so that the cips couldn't use the sensor. The same chips were horribly rich under full throttle. GURU chips also use the O2 sensor for idle/part throttle, and pass emmisions testing no problem. Might be different on the NA cars though (FRWilk.)
