I guess its just my luck but I have had issues with the FPRV in the past.
http://i689.photobucket.com/albums/vv257/BRD-PREY/4valves_zpsce2c4dbe.jpg
So, here is a quick way to update your FPRV. If your our running an upgraded High Pressure Fuel Pump (HPFP) then you are putting your stock valve through more cycling then it was designed to do. The stock FPRV spec is 130 bar. I had a RS4 136 bar FPRV and I am replacing it with a 145 bar from HPFP upgrade they are a company that specializing in upgrading our pumps.
My first FPRV stuck open and the car went into limp mode on the way back from a trip. My second relief valve after 6 months would open at 80 bar. I am replacing the 136 bar FPRV because I have logs of it opening on rail pressures spikes on full throttle and when it opens the pressure drops to around 80 bar. Now the spikes could be caused but the N276 but it still is not good for the FPRV to be cycling.
- Remove engine cover.
- Remove and interference like cold air snorkel etc.
- Remove the 2 screws holding the fuel lines and the 17mm fitting holding the HPFP output line.
- Remove the divertor valve.
- Remove the bracket for the Divertor valve.
- Remove the fitting 14mm crowfoot from the back of the relief valve.
- Work the hardline out of the way.
- Remove the FPRV with a 17mm crowfoot. You can reach in from the top and use a screwdriver to help your fingers rotate the valve.
- Reverse the steps and your done. The hardest part is forcing your fingers in to rotate the new valve in. Use a wire or whatever you have to help guide it from the top.
http://i689.photobucket.com/albums/vv257/BRD-PREY/Enginebay_zps82be69df.jpg
http://i689.photobucket.com/albums/vv257/BRD-PREY/HPFP_zps36e648fa.jpg
http://i689.photobucket.com/albums/vv257/BRD-PREY/screwdriverhandlewedge_zps46f1ca37.jpg
http://i689.photobucket.com/albums/vv257/BRD-PREY/FPRVlocation_zps7f8c79ea.jpg
http://i689.photobucket.com/albums/vv257/BRD-PREY/tools_zpsa3ef3e02.jpg