CEL help

[dagibby]

pulled code P 2407 from my 2003 XC70 today. Code read as follows; Evaporative emissions system leak detection pump sensor circuit intermittent/erratic. Check engine light stayed off after reset for exactly three starts. Gas cap tightly sealed with 3/4 (no more) tank of high test gas. What is wrong and how do I get rid of this damned light?

[JRL]

There are several parts to the evap system, not just the gas cap.

[dagibby]

I was hoping to bypass ten people telling me to tighten the gas cap. Is there any listing for Volvo OBD II error codes on the web?

[MoeB]

I have seen a P code conversion chart on the 'net somewhere but can't find the link right now. From your code description it sounds like a bad vacuum hose or connection and/or a faulty tank pressure sensor.

If I can find the conversion link I'll post it.

[BillAileo]

According to VADIS one of the components of your evaporative emission system is a "leak diagnostic unit". I believe this contains the pump that creates the vacuum in the system. Perhaps the electrical connections to that pump have an intermittant failure, or the pump/sensor are failing?


Bill

[dagibby]

Check engine light will stay off after reset until refuel. Careful not to overfill and purchased new gas cap. Where is the sensor that would throw the code? At this point, I'd be happy cutting a wire or disabling the sensor to keep the damned light off.

[Willy]

You can find the complete wiring diagrams here:
http://www.twango.com/media/Gear-Up.Volvoxc/Gear-Up.10046
The file not only contains the diagrams themselves, but also component locations
so you should be able to find where the pressure sensor for the tightness test of
the fuel system can be found. I think that "cutting the wire" of the sensor may not help,
the monitor runs as follows: either a pressure or vacuum is applied to the system,
"locked up", and afterward the presence of the pressure/vacuum is tested by means of
the sensor. If so, the system has no leaks. I think that by disabling the sensor, you
may end up with the error every time!
As a matter of interest, see this site:
http://www.fordscorpio.info/evapmonitor.htm
It gives a good idea of what is going on, and last but not least, it is about a Ford :D
Willy

[JRL]

Check engine light will stay off after reset until refuel. Careful not to overfill and purchased new gas cap. Where is the sensor that would throw the code? At this point, I'd be happy cutting a wire or disabling the sensor to keep the damned light off.

"Cutting a wire" won't help, plus the car STILL won't pass emisions

[dagibby]

I wasn't serious about cutting wires, just frustrated. Oddly though, now that you mention it, the car just passed emissions last month...

[dagibby]

thanks for the links, I was wanting a wiring diagram....any chance you know where to find XC OBD II codes?

[thebracko]

Sometimes this code is fixed with a software upgrade. Leakage detection pump failures are not uncommon either though.

Regardless, you're unlikely to fix this in your driveway. You'll need to bring it in to your dealer to fault trace as per VIDA.