This looks like the part you took a picture of: 1999 Volvo S70 Replacement Fuel Pressure Regulators at CARiD.com. That is a pressure dampener.

This is a link to a video RSPI published the other day for PCV service. Look at the fuel rail at the 18:30+ minute mark. He has it upside down and you can see . Keep in mind the video is a 1994 so its a little different than yours. Maybe somone else can give you details on a 1999 S70. https://volvoforums.com/forum/volvo-...t-video-74992/

Here is a link to a pressure regulator. New Volvo Bosch Fuel Pressure Regulator 1995 1999 | eBay

The vacuum connection on a pressure regulator is the feedback to the regulator as the engine speed changes.

You should take several more pictures around the fuel rail. In the right picture it appears that the far left injector connector is either broken, damaged or incorrectly attached, biut its hard to tell.

I'd open the hood and look at mine, but its seriously cold outside and dark and mine is a 2000.

 

The car I did the PCV on was a '95 turbo but I did show a few clips of a '94 NA.

 

OK yes I will check that injectors connection. It does look funky in he picture.

The regulator is not on the rail. YEs that appears to be the dampener. Any idea where its located?

 

I am convinced the problem lies with the fuel pressure regulator but I cannot locate it. Please direct me.

 

The important thing for fuel pressure regulators is the pressure. 43 psi someone said. Buy/borrow one from autozone where you bought the pump. I looked at a 99 rail on ebay and it also shows just the dampener on the rail. You can clearly order the part so it must exist somewhere, unless its one of those mid-year model things. Maybe someone with 99 experience can shed light on this.

On another thread I saw a note about the IAC (Idle Air Control). Is the IAC connector on? Vacuum hoses connected on the tree?

Is this turbo or non-turbo?

 

non turbo. where would I hook in a fuel pres gague on the rail?

 

looking at the rail there is a shroder valve on the right side. It should have a cap on it. Your fuel pressure tester screws onto the shroder valve. Put a paper towel or rag under the shroder valve to absorb any gas tha tleaks out. Remove the paper towel before starting the engine, just in case.

Since you car isn;t starting, you may want to position the guage so you can see it while the engine is cranking.

 

ok will do. now what about the location of said fuel pressure regulator?

 

Take 1 step at a time. If you get about 43 psi, folowing what I said, you don't have to worry about the fuel pump, dampener, pressure regulator or anything in that circuit. That alone will tell you that you have fuel pressure to start the car.

If the fuel pressure starts at 40 psi and then drops way off as you crank it, report that back here.

Did you check the IAC connection? I dont; believe it will start without that connected.

 

ok I'll see if I can get a fuel pressure gauge from autozone or whatever.

Not sure where the IAC is either. why cant anyone point me in the direction of these thing instead of talking past them?

where is FPR and IAC

 

This is a picture of an IAC. It's under the throttle body cover. You need a T25 to take the cover off.
93 2004 Volvo 850 960 C70 S70 V70 XC70 Idle Air Control Valve IAC 0 280 140 542 | eBay

After I wrote this I looked something up and it shows that the 1999 S70 may not have a seperate IAC and idle air may be electronically controlled by the throttle body. You will have to figure that out from the picture and looking at the car.

We are just trying to help you past your problem. My concern is you have disconnected something and not re-connected it when you put the rail back on.

I still think it would be very helpful to have you take pictures so people can see what you see and provide specific help. Example, take the plastic cover off the throttle body (look at RSPI's head removal video, it shows the throttle body cover and how to remove it. It will show you the IAC and the wiring for it. It will show you the vacuum tree and the hoses to it). I would not take anymore stuff apart until you can identify what is going on. The point of the connector on the IAC was a shot in the dark thinking maybe you disconnected the connector when you took the rail off.

 

 

Thanks for the video. Very first problem you have is fuel pressure. What you have there is a vacuum guage, which is why it only goes to like 10 psi. Your fuel pressure should be 40+ psi. You have 6 psi and it tapers off. That implies to me your pump is not running or pressure regulation. Before you can go further you need to know your pump is actually running.

Find the fuel line going to the rail. I thought it about half way on the rial to the left of the dampener in your earlier picture. That looks to clamp to the rail. Follow that back to where it converts to the metal line. Take that off and use a pice of replacement hose and attach it. Get a good sized jar and put the other end in the jar. Turn the key to ON and watch how it pumps. It should be a good strong stream. It should not take long to fill the jar so keep close to the key and turn it off without pouring gas everywhere.

If you get a poor or no flow the pump or the relay or power is still the issue. The relay is a known issue. On the relay will show the pinout of the relay. I recall in an earlier post that you jumpered the relay along the way. You need to make sure you didn;t blow the fuse. Pull the relay and make sure you have 12 volts for the relay N.O. (normally open) circuit. Check both sides of it as Ihave no idea which side has the power. You may need the key in the ON pposition. With the key ON, you should have 12V on the relay for the coil as well. One side of the coil goes to ground, the other to 12V. When you turn the key On, that engages the relay coil which converts the relay from N.O. to N.C. If you do nto have 12 V then you need to find the fuse and fix that first.

Report back what you find.

 

If you have any pressure then pump is running, yes?

kwatt; know you're trying to help but don't think you understand this system; this is '99 MY and the electronic fuel injection (EFI) changed from Return-type to Returnless type that year. Here's a site w/lots of good info on that.

Diagnosing Returnless Fuel Injection Systems

The fuel pressure regulator was on the rail in '98 and earlier models but not on '99 and later. I did a google search but having trouble finding a good source for exactly where the regulator is on '99 and later volvos. Seems they have a fuel pressure sensor somewhere in the system; that gives input to the ECU which regulates the fuel pressure by modulating the fuel pump voltage supply (assuming PWM). And from what I'm reading this system is very prone to failure.

Here's one thread on topic:
Fuel pressure regulator


To OP:

1. What did you see when you replaced the fuel pump? Was there other stuff in there besides the pump?
2. Still want to know how you cleaned those injectors?

 

Gdog, you are right about the assessment. I have 2000 but with the cold and rain here I was nto willing to jump under the hood to take a look in comparison - I guess I should have whe offering opinion/advice. The internet parts places have the FPR listed so I am thinking maybe its one of those model year changes??? And the 6 psi suggests the pump runs (as you stated) so there is power. Somewhere there has to be presure regulation and a return. Maybe the return is internal to the tank as part of the fuel pump assembly.

It would be interesting to jumper the relay, or replace it, to see if the pressure changes. There are so many issues posted related to the FP relay. I had a valuable lesson on the wifes Benz and the relay for the airmatic compressor. Locked up on and burned up the compressor. $600 compressor because of a $20 relay. I keep a spare relay in the glove box now.

Back to this issue.... given your experience and what he is describing, including the video, would you agree the 6 psi pressure is the first issue to tackle?

 

When I watched the video, it looks to me that he has good pressure.

I do NOT have a fuel pressure gauge and have NEVER checked fuel pressure but that looks like a brand new gauge that may do multiple functions. I actually paused the video when pressure was up on the gauge. The right side of the gauge, the inner range, actually says FUEL PRESSURE then goes on to have that x10 note near the top which leads me to believe he has good pressure.

Now as to why the car is not starting??? That is a mystery but it's hard to help someone that will not listen to the basics.

Cars that have combustion motors have the same basic 5 needs. Sure auto manufacturers have complicated the hell out of how the 5 basics are delivered but the basics are still the same. So, those 5 basic things need to be checked / tested if at all possible. Not 1 thing, all 5.

Then there is the factor of joining a forum and hoping like hell that someone that is an enthusiasts, that has spent countless hours on forums and tinkering will find your post and have enough compassion to try to help you...

It seems that the op has taken his ball and gone elsewhere. Hopefully he called a wrecker and had the car taken to a good shop that can help put the car back together and has him back on the road. Kwatt made it clear that he was feeding knowledge of pre '99 cars so that should not have been a big deal. At any rate, I don't believe fuel pressure is an issue.

Hopefully the op will have the decancy to return and post the results so others can benefit from the thread.

 

Oh, and as for the location of the fpr... it's in line with the fuel lines. There is only so many feet of fuel line on the car, follow them until you find the regulator. If we knew exactly where it is, we would have told you. No one is trying to jerk your chain by withholding that information.