Monday, March 5, 2012

Fuel Pressure Sensor

An OBD-II Scanner is an important tool to decipher error codes. Error code P0192 on the Volvo S40i means "Fuel Rail Pressure Sensor Circuit Low Input". A common problem is a defective Fuel Rail Pressure Sensor.
The first thing to do before replacing the sensor is to depressurise the Fuel System. Make sure you are wearing proper clothing and eye protection when working with fuel systems. Inside the fuse box next to the car battery you can find a fuse clamp.


Use the clamp to remove fuse #74 for the fuel pump relay in the fuse box under the passenger glove compartment.


Start the engine and wait until it stops. I had to wait for more than 2 minutes for the engine to die.
Remove the 2 retaining screws of the air intake that covers the pressure sensor. Disconnect the wiring connector to the sensor. Make sure you place some old rags under the pressure sensor to catch any fuel spillage. Remove the retaining screw of the pressure sensor and slowly remove the pressure sensor. You might hear a pop sound. Replace it with a new one and assemble everything back together.




Total repair time is about 30 minutes.

Trunk Lid Open Warning Light


"Trunk Lid Open" warning light on the dashboard might be caused by a broken wire near the trunk hinge. Pull down the cable shroud near the hinge and check if there is any broken wire as shown in the picture. Solder the broken wire and then use heatshrink to cover it. I used electrical tape since I did not have my heat gun with me. Reinstall the shroud and you are done. Thanks to JondevieonS40 from VolvoForums for the solution. Total repair time is about 15-20 minutes.

Windshield Washer

If your windshield washer system is clogged. That is you hear the pump sound but there is no fluid coming out, then either your fuild level is too low or somewhere is clogged in the system. If it is the first case then add more washer fluid and you are done. But most probably your washer system is clogged or a part needs to be replaced. First check the jet nozzle, then work the way down the line. For my case, the filter of the pump was clogged.
To clean the pump, first suck out as much out from the resevoir. I snaked down a discarded refrigerator water tube, sucked it and let pressure and gravity (siphon principle) works its magic. Make sure you are also working outside in case you do not manage to empty the resevoir and leftover fluid wets the floor. Turn your wheels all the way out so you have ample of space to work. The washer pump is under the resevoir and the easier way to access it is through the wheel mud cover on the driver side. Remove the Torx screws and hex screw and then remove the wheel mud cover. The pump is not visible, but you should be able to feel it with your hand hidden behind the resevoir. There is a electrical cable going in and tube going out toward the jet nozzle. Use your hand and carefully pull out the pump without damaging the gasket. There is a mesh on the inlet of the pump that was clogged, so I cleanned it and reinstalled it. Pour some washer fluid and make sure there is no leak. Finally reinstall the mud cover and screws.
The cleaning/replacement of the washer pump should take 30-45 minutes.

The Starting Line

My 2005 Volvo S40 2.5i will take me on a journey through two path: one on the road and another in the garage. Here are some handy tools you might find useful for your journey.
 I am not a mechanic, so follow my instruction at your own risk.
Before you start, find out if there is a recall for the problem from your service center. Volvo willl repair it for free if the problem is in the recall list.

The following link shows the recommended Maintenance Schedule Operations by the manufacturer.