shegarty writes »
I’ve been chasing a hard start at temperatures below -15ºC on my 98 S70 for a couple of years now. I believe that I have narrowed it down to a fuel pressure issue as I have replaced most of the electrical components (cam & crank sensors, plugs and wires etc.). As I always start with the least expensive components first I would like to replace the fuel pressure regulator before the pump. I understand that these don’t go bad often but I would have to replace the entire pump assembly to rule out a bad check valve and besides it’s damn cold up here in the great white north these days and with no inside space I don’t relish the thought of replacing the pump. Anyways, I need help locating a part number as I have the regulator that sits above the steering rack and both FCP and iPd only seem to have the type that either sits on the fuel rail (mine has the pulsation damper there) or mounts back near the fuel filter.
Then he adds
It looks like I have solved the issue by replacing vacuum lines – both the large line to the manifold and the smaller line to the nipple by the MAF. She started right up this morning in -23ºC, well maybe not right up but only cranked for 3-4 sec and that was without a block heater. Thanks for all the help folks.
Smell gasoline in your Volvo? It might be the FPR. See this tutorial on how to change out your fuel pressure regulator on 850, S70, V70, XC70 & other 5-cylinder Volvos.
michael8888 writes some good info on FPR availability, for his 1998 V70 T5, not the same engine as shegarty’s S70:
Long Crank on a 1998 — Diagnosing FPR & Vacuum Lines
I haven’t seen an oem or Bosch fpr for my 98 on ebay in 6 months. However, after doing some research it seems the specs on the bosch 0280160574 which is the one in my 98 t5m is a 3.8Bars FPR. The Bosch 0280160575 is for 4bars. Bosch does make 3.8Bar FPR #0280160689. It is also a lot more expensive. 3.8Bars = 55.11Psi and 4bars = 58.01Psi. The difference of 2.9Psi to my understanding may not be an issue if you are running bigger injectors and if you need the addition flow rate at full throttle. However if my fuel pump is getting weak i may not get enough pressure at the fpr at all times or if i have a vacuum leak the fuel pump will be trying to keep the pressure up at idle.