Installed BBK longtube headers and engine runs better without oxygen sensors!!!

I

Ishman 306

Founding Member

May 18, 2001

67

0

6

St Petersburg, FL

Sep 20, 2007

#1

• Sep 20, 2007

• #1

I've been trying to track down this probem I've been having after the BBK ceramic coated longtube header install. The car would idle like it had a huge vacuum leak half the time and it would buck and pop up to 3000 rpm, and then after it hit 3k rpm all the sudden run fine! I've tried just about everything (and I mean everything!, even put in new engine harness) until last night i unplugged the O2 sensor harness, and wham idles smooth as silk and doesn't buck or pop. What gives?

Scott

 

pwcracer

Founding Member

Jun 13, 2000

347

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16

Hastings, MN, USA

Sep 20, 2007

#2

• Sep 20, 2007

• #2

Isn't there something with long tubes that needs to be corrected in the ecc? I know when I had my tweecer there was some things I had to change due the longtubes. Same with the chip I had burned..

 

SVT32VDOHC

waiting for the next hack atta

Founding Member

Nov 22, 2001

3,501

28

119

Motor City

Sep 20, 2007

#3

• Sep 20, 2007

• #3

You needed a tune.

 

juiced_94gt

Active Member

Mar 30, 2005

1,143

0

36

Southern California

Sep 20, 2007

#4

• Sep 20, 2007

• #4

you need a tune, when you install longtubes the o2 sensor is further downstream and they dont heat up like in the stock location, mine did the same thing and my tuner told me it was because of the lt's now after the tune it runs like stock.

 

stykthyn

I want to measure mine. It doesn't look that tall.

15 Year Member

Jul 6, 2006

5,232

2,652

223

gainesville

Sep 20, 2007

#5

• Sep 20, 2007

• #5

do you really need the sensors?

 

F

Fox8950

Member

Jun 29, 2007

247

2

18

Sep 20, 2007

#6

• Sep 20, 2007

• #6

I wouldn't drive without em. When your not WOT they decide the fuel mixture do they not?

 

BK_CAULEY

it's built for speed not longevity, woman

Dec 26, 2006

0

10

49

Thomasville, ga

Sep 20, 2007

#7

• Sep 20, 2007

• #7

the sensors are there for a reason and the reason your car runs better with out them is because they are probably damaged and giving false readings.

 

I

Ishman 306

Founding Member

May 18, 2001

67

0

6

St Petersburg, FL

Sep 21, 2007

#8

• Sep 21, 2007

• #8

I've considered getting a tweecar. The O2's themselves aren't the probem, I've tried 3 different sets!!! lol

Someone mentioned that the Air Intake Temp sensor works in conjunction with the O2's and maybe that sensor could be bad and when I unplug the O2's it goes into open loop and ignores the "bad" AIT??? any thoughts?

Scott

 

bullitstang1313

Member

Jan 21, 2003

713

0

16

Indianapolis / Columbus, Indiana

Sep 21, 2007

#9

• Sep 21, 2007

• #9

Its like svt32v and juiced_94gt said, you need a tune. Since the O2 sensors are now farther away from the engine they need a longer time to warm-up properly. Since the ECM doesn't know that, it thinks that the O2 sensors are warm and it causes the A/F ratio to be wrong so it starts changing fueling to componsate. You definately need to have the O2's in order for good driveability and proper closed loop operation.