cel after install of dansk headers

[carmos]

hi all, i have an 04 box s...i recently installed dansk headers..the problem was the 04 has 4 o2 sensors while the headers only have 2 o2 connectots... i was to told by the people who sold me the headers..vertix automotive out of miami..to take it to my mufffler guy and have him weld the 2nd set of 02 sensors just behind the 2nd set of cats on my car..i did and the cel was off for awhile but at 264 miles after the mod to the rear cats .the cel came back on..my question is ,is there a work around for this or do i have to buy the dansk hi flow cats also? and do they already have the connectors for the 2nd o2 sensors...thanks in advance for any help

p.s. the cel code i am getting is p2096--signal dely time for oxygen sensor ageing

Edited September 9, 2005 by carmos

[insite]

if the o2 sensors aren't the exact same distance from the cats, you'll get MIL light. my guess is that they are currently too far away from the cats, so the car thinks that the o2 sensors are reacting too slowly.

think of it this way: the car knows the distance between sensor 1 and sensor 2. it also knows the relative velocity of exhaust. say one 'pulse' of exhaust passes sensor 1 and is anylized. the car looks for sensor 2 to confirm this same 'pulse' of exhaust a split second later as it passes sensor 2. on your car, sensor 2 is too far away, so the sensor takes longer than expected to react. the car assumes the o2 sensor is old.

there is also the possibility that the o2 sensor was indeed damaged during removal / replacement. also, porsche oem o2 sensors use the wire itself to 'breathe' clean air with which to compare the exhaust readings, so if the wire is damaged / blocked up, the readings will be bad.

i recommend first unplugging the sensors and checking / cleaning the wire harnesses from the sensors. if that doesn't work, replace the sensor. if that still doesn't work, you will have to have the sensor mounting points moved toward the cats a bit.

[MNBoxster]

if the o2 sensors aren't the exact same distance from the cats, you'll get MIL light.  my guess is that they are currently too far away from the cats, so the car thinks that the o2 sensors are reacting too slowly.

think of it this way:  the car knows the distance between sensor 1 and sensor 2.  it also knows the relative velocity of exhaust.  say one 'pulse' of exhaust passes sensor 1 and is anylized.  the car looks for sensor 2 to confirm this same 'pulse' of exhaust a split second later as it passes sensor 2.  on your car, sensor 2 is too far away, so the sensor takes longer than expected to react.  the car assumes the o2 sensor is old.

there is also the possibility that the o2 sensor was indeed damaged during removal / replacement.  also, porsche oem o2 sensors use the wire itself to 'breathe' clean air with which to compare the exhaust readings, so if the wire is damaged / blocked up, the readings will be bad. 

i recommend first unplugging the sensors and checking / cleaning the wire harnesses from the sensors.  if that doesn't work, replace the sensor.  if that still doesn't work, you will have to have the sensor mounting points moved toward the cats a bit.

<{POST_SNAPBACK}>

WOW!!

A Car which cannot keep it's oil contained behind the RMS with any degree of certainty is sophisticated enough to sample individual Exhaust Pulses? Does NASA know this? :huh:

Sorry, but my money is on either a damaged electrical harness or damaged O² sensor(s).

Happy Motoring!... Jim'99

[carmos]

thanks for your answers guys..i reset the cel and it was off for 259 miles....then today i went to the german autofest in ventura california and had the guys from evo in arizona install the giac upgrade to the ecu..it has been 180 miloes since the ecu flash still no cel...so i have my fingers crossed..as for the ecu flash i noticed a bit better throtlle response and between 3500 rpm and 4500 rpm a good boost in power... :D

p.s. also got the smartop plug for the top...thats is nice!!!!!! no more e-brake to drop the top and it works up to about 28 mph...

[erics]

did you update only the headers?

Or the while exhaust system: headers + cats + sport exhaust?

What is the result?

Sound?

Performance?

[carmos]

hi erics,i did the headers from dansk,magnaflow exhaust,giac chip and today i got my evo intake installed at aj usa in sandeigo..i hit traffic all the home so i have not really tested the car yet..i an going back on friday to san diego to dyno test it if all goes well...i will post results as soon as i have somthing... <_<

[erics]

yes pls.... (+ let us know on the noise too => boomy or ok?)

[carmos]

Hi erics, here are my dyno nunbers after danks headers,magnaflow mufflers, evo intake and revo ecu mod..246 h.p.to the wheels is not to bad.the car did not like the giac ecu mode ran pretty rich and preformace was pretty bad..now it runs great and there is a very good gain from 3500 rpm to 5500 rpm..mark over at Hergesheimer in lake forest in o.c. was very helpful.if you can take your car there i think you will like what they can do for you.. :D

[erics]

Hi Carmos, many thanks for the info.

So it is 246 hp at the wheels vs 225 hp when the car is standard?

I am in the UK actually so would need to find someone willing to do the same in London (or near).

Is the noise much changed now?

[carmos]

hi erics, yes the car is alot louder..everyone tells me it sounds like a "race car"...i think if you want something only little louder,get the dansk muffler..plus i think that muffler gives you like 1 to 3 horsepower by it self... :D

Hi Carmos, many thanks for the info.

So it is 246 hp at the wheels vs 225 hp when the car is standard?

I am in the UK actually so would need to find someone willing to do the same in London (or near).

Is the noise much changed now?

<{POST_SNAPBACK}>

[clubhead]

...the car did not like the giac ecu mode ran pretty rich and preformace was pretty bad.....

Now, I'm glad at least another decent person dynoed his car after mods instead of relying on butt dyno. I've the same experience with GIAC last year and returned the ECU to them for a refund. All those so far that raved about GIAC have no dyno figures to show.

To answer your earlier question, the Dansk Sports cat does not come with any pre-drilled holes for your 2nd O2 sensor. I've them on but thankfully, my car only has 1 set of O2 sensors :)