View Full Version : sensors on cat
the sensor that is just after the cat, is it needed once u fit a de cat pipe. does it alter fuel etc.
any help
You can't de-cat your car (with 2 sensors), becase CEL (check engine light) will illuminate. The second sensor is for testing the CAT itself.
yes i can de-cat it. i know light will come on. does this sensor if taken out have any significance with fuel or air ratios.
chriskaven
18-03-2004, 20:05
It will only trim fuel ratio very slightly for fuel economy in cruise conditions so you might see a drop in fuel economy.
When you go wide open throttle this sensor is not used anyway, however if your diagnostic light is lit, you dont have any warning if anything else goes wrong.
The second O2 has nothing to do with the fuel/engine management.
Surfer_D
20-03-2004, 11:03
You can't de-cat your car (with 2 sensors), becase CEL (check engine light) will illuminate. The second sensor is for testing the CAT itself.
Yes he can I did it and I'm driving it like this for 20k. Who cares about the stupid light :) 25hp guaranteed
CupraR-Rog
20-03-2004, 13:42
25hp guaranteed
Erm... no... look at the Stealth RR day, and you'll see a chipped & de-catted LCR getting less than chipped-only LCR's, which were understandably less than a chipped LCR with race cat & milltek system...
OK, they're LCR's and not Ibiza Cupra's, but it's the same-ish engine...
Surfer_D
22-03-2004, 09:04
Erm... no... look at the Stealth RR day, and you'll see a chipped & de-catted LCR getting less than chipped-only LCR's, which were understandably less than a chipped LCR with race cat & milltek system...
OK, they're LCR's and not Ibiza Cupra's, but it's the same-ish engine...
I could be due to the faulty maf sensors. Dyno plots that I did confirm that you get 25hp with full turbo back system.
Well, if i knew that the CEL is lit because of NO cat, then i would not worry. But what's when other important error(s) occour, you wont notice it coz your CEL is already on.
BTW: How about using the same singal from pre CAT O2 for post CAT O2? Just an idea.
Surfer_D
22-03-2004, 11:42
Well, if i knew that the CEL is lit because of NO cat, then i would not worry. But what's when other important error(s) occour, you wont notice it coz your CEL is already on.
There are two options.
1.
You can install different o2 sesnsor which would lie and always show the right value.
2.
Use VAG-COM as we all do
Use VAG-COM as we all do
Hey! Dont show off! ;) Just got myself a decent notebook (P4-2.6, Radeon9600-128), so VAGCOM here i come!