2003 NA S60 fuel pressure woes

EivlEvo · Post by **EivlEvo** » 03 Jan 2016, 13:11

Greetings.

I'm working through an odd problem with an 03 S60 with the NA 2.4. The car for about a month has hesitated to start. Cranks like a champ, but won't fire. On Christmas eve, it refused to go no matter what I did.

I've hooked my gauge up to the fuel rail and not only was there no residual pressure, but no pressure registered even through extended cranking. Well, we arrived back home this morning from a trip and I got it to stumble to life (nothing has changed... It's colder now actually). Got it positioned further up the drive and started in on it.

Fuses are all good. The relay (which I've now found at ci12) is clicking (does anyone have a proper test for this?) and upon checking the fuel pressure, it sits at about 15psi. This seems quite low to me. Does anyone happen to know the pressure range? But the pressure does not dip upon shutdown, so I suspect my fpr and check valve are in order.

Any other thoughts?

Questions I'd love to hear feedback on specifically...
1. What is the normal fuel pressure at the Schrader valve on the fuel rail?
2. Is there a proper test for the fuel pump relay? Does anyone know the resistance etc.?

Thanks crew.

Post by **scot850** » 03 Jan 2016, 15:10

Fuel pressure should be >43psi

Can't answer about the testing of the fuel pump replay, but if you search here there is a way to bridge the connectors to bypass the fuel pump to test for its function.

Neil.

EivlEvo · Post by **EivlEvo** » 03 Jan 2016, 20:12

Ok then... so with the pressure reading that low, I definitely have a pressure issue. Where does this leave me? Should I be investigating the pump as failing, or is this an FPR issue or what?

Post by **scot850** » 04 Jan 2016, 11:30

Before consigning the fuel pump, has the fuel filter been replaced recently? IF these get clogged they can cause fuel pressure delivery problems. Does the pump sound particularly loud?

Did you look into the fuel pump relay bypass to eliminate that also?

It is always worthwhile pulling a spare from a scrap car, testing it in your car and keeping it as a spare if it is good.

These are the cheaper options before springing for the fuel pump.

I am not familiar with the S60 fuel system for the newer cars, but from looking at Vida, it is not too difficult to replace the pump but it is expensive for parts, and Volvo has added a fuel pump controller to the car as well. Looking at FCP Euro for parts prices, the controller (Volvo is about $360 US) and the pump about the same. There is also a fuel pressure damper. I'd look to others here to find out if there is a way to check each part without buying replacements. Not sure if the system can be 'read' to identify the issue.

Neil.

EivlEvo · Post by **EivlEvo** » 05 Jan 2016, 13:22

Neil. Thanks. My vehicle is a metal tank vehicle that has the filter as part of the pump. If the fuel pump controller went bad, I feel like if get a code? Same with really anything aside from the pump or the relay?

Honestly though I'm not too sure. If others have input, is love to get it. I have no problem performing the repairs, but I agree... I don't want to just throw parts at it...

Post by **abscate** » 05 Jan 2016, 14:09

Im not sure you will get a code from low fuel pressure on a 2003. Jump the relay and see if you get 50 psi pressure at the rail. Without that pressure, it won't run right.

Relay
wiring
Fuel pump

are likely culprits, ordered in probability.

Post by **scot850** » 05 Jan 2016, 15:37

I agree with abscate on this.

Neil.

Post by **DGM** » 06 Jan 2016, 06:38

EivlEvo wrote:Neil. Thanks. My vehicle is a metal tank vehicle that has the filter as part of the pump. If the fuel pump controller went bad, I feel like if get a code? Same with really anything aside from the pump or the relay?

Honestly though I'm not too sure. If others have input, is love to get it. I have no problem performing the repairs, but I agree... I don't want to just throw parts at it...

I had the same problem last winter with a V70 NA. No code. What type of fuel system have you? If your car is equipped with the fuel pressure sensor at the end of fuel rail, then you have a fuel pump module (called PEM by Volvo) installed on the top right front corner of the fuel tank (steel tank). Components inside can go bad. Also corrosion on the connector contacts. Remove it and verify when you shake it close to your ear if it has loose particles inside.

A bad FPS is also possible but normally you get a code.

FPS

: FPS.jpg (19.56 KiB) Viewed 4421 times

PEM

: PEM.png (213.13 KiB) Viewed 4421 times

EivlEvo · Post by **EivlEvo** » 08 Jan 2016, 16:09

DGM wrote:
EivlEvo wrote:Neil. Thanks. My vehicle is a metal tank vehicle that has the filter as part of the pump. If the fuel pump controller went bad, I feel like if get a code? Same with really anything aside from the pump or the relay?

Honestly though I'm not too sure. If others have input, is love to get it. I have no problem performing the repairs, but I agree... I don't want to just throw parts at it...
I had the same problem last winter with a V70 NA. No code. What type of fuel system have you? If your car is equipped with the fuel pressure sensor at the end of fuel rail, then you have a fuel pump module (called PEM by Volvo) installed on the top right front corner of the fuel tank (steel tank). Components inside can go bad. Also corrosion on the connector contacts. Remove it and verify when you shake it close to your ear if it has loose particles inside.

A bad FPS is also possible but normally you get a code.

FPS

FPS.jpg

PEM

PEM.png

DGM... I have that fuel system actually. I just read a TSB about Volvo having mechs move these PEMs inside the cabin. Where is it located exactly? Is it on top of the tank? Like... am I dropping the tank to see it, or do I access it the same way I access the pump?

Additionally, I've checked the relay and it's healthy and well within spec. The question that I have is... the pump is pumping sometimes obviously... and in fact, the car will never stall from a running condition. Only offer up no starts.

On one hand, this makes me think it's the PEMs connections, and there's simply enough fuel in the lines to handle keeping the car going when the PEM arcs out.

On the other, why would the fuel pressure be so low?

Post by **DGM** » 09 Jan 2016, 13:10

" DGM... I have that fuel system actually. I just read a TSB about Volvo having mechs move these PEMs inside the cabin. Where is it located exactly? Is it on top of the tank? Like... am I dropping the tank to see it, or do I access it the same way I access the pump?"

For most models Volvo sells an harness to relocate the PEM in the spare tire compartment. However the last time I checked this harness would not fit our steel tank applications because of the way the wiring is arranged on top of the tank. You can access the PEM by under. It is installed in a bracket on the top right front corner of the steel tank. There is a little screw which must be undo. This will remove tension on a metal strip that secure the module on the tank. You pull the PEM back and up to remove it from the bracket. Then you have to push on a small tab (be careful easy to break) on the electrical connector to unplug it from the PEM.

"Additionally, I've checked the relay and it's healthy and well within spec. The question that I have is... the pump is pumping sometimes obviously... and in fact, the car will never stall from a running condition. Only offer up no starts.

On one hand, this makes me think it's the PEMs connections, and there's simply enough fuel in the lines to handle keeping the car going when the PEM arcs out.

On the other, why would the fuel pressure be so low?"

Normally 55psi is the reading at the fuel rail for this FPS/PEM system. The Fuel Pressure Sensor monitors pressure and informs the ECM. In turn it controls the PEM (4/83) through a pulse width modulated signal to maintain the right pressure.

The pump (6/33) isn't running full blast. Its speed changes depending of fuel needs ( control by the PEM). See the S60 2004 diagram I found on the WEB for more information. Vida can indicate the duty cycle at which the fuel system operates.

For whatever reason electronic components inside the module (PEM) degrades and the control of the fuel pump becomes intermittent. That is why I mentioned to check for loose particles. Xemodex sells rebuilt sealed units that are well suited for applications like ours that are mounted on the tank.

Hope this help,