1999-2009 [Subscribe to Daily Digest] |
Recently installed a 3" downpipe with Magnaflow cat on my 2006 9-5 and started to see the infamous p0240 error. Have been doing some research on the various fixes, and came across this one that seems to be a nice solution. It was on a WRX board and I'm looking to adopt it to SAAB. Since this fix is wired into the o2 sensor leads, it should get past the pollution police, yet not defeat the purpose of the rear o2 sensor, which is mainly to monitor the health of the catalytic converter.
Can some evaluate the circuit below and 1) identify which wires on the SAAB o2 connector are used and 2) evaluate it as a fix for
the p0240 error.
If I understand it right, the p0240 occurs when the ECU detects more that 75% difference between the front and rear o2 sensors on 3 consecutive duty cycles. The o2 sensor sends between 0 and 1 volts to the ECU, depending on how much o2 it detects. An low-restriction exhaust can trigger a low reading by allowing better exhaust gas flow, which will result o2 readings lower than with a regular cat, especially when cruising at a steady speed. This fix should level out the readings, but I'm not an electrical engineer so can't evaluate it.
1 k ohm resistor
________________/\/\/\/\/\/\/\/\/\/\/\/\_________________
| |
| |________
___|___ |
_______ 1 micro farad Capacitor
|
| |
| ________|
________|_______________________________________________|
<-- To connector to o2 sensor -->
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.