Hello all,

New owner of a 2007 S40 with 150K, 2.4i, manual. Here is my issue. Just had the timing belt done by Volvo Dealership and ever since there is a issue with starting it. When it has sat for a while (4+ hours) and you go to start it, most of the time it will turn over like there is no fuel and keep turning over. When you try a second time, it fires right up and acts completely normal. Volvo has looked at it and it sounds like a Fuel Pressure Regulator issue, but they don't have one after 2004. I have read on the forum of many issues with the pre-2005 S40 and replacing the FPR took care of it. This is the same exact problem, but Volvo doesn't have any more ideas other than start replacing likely problems. Fuel Pressure Sensor ($300.00), fuel pump ($800.00).....and so on. I have asked them to put a pressure guage on the fuel rail or connector to see if the fuel pump is losing pressure while it sits.... I am out of options and don't want to dump a lot of $$ into this. Any ideas what my issue might be?

 

This is really bad. They do not know how to diagnose a problem? Simply throw YOUR money at it? Run away from that dealer. You are absolutely correct with your thoughts. Put a fuel pressure gauge on it and see what happens. No guessing, no throwing parts at it.

 

Yeah, they should know how to diagnose this, it isn't hard. They need to check fuel pressure overnight.

 

Yeah, it's pathetic. I told them if I have to tell them how to diagnose problems I am going to have to charge them 120.00/hr for my services. They didn't laugh. Will let you know what comes of this. Still waiting for a return phone call from them. Their suggestion as a fix yesterday......"Just live with it", it's not that annoying!! WOW!

 

I'd recommend contacting Volvo Customer Care about this, they'll get someone else involved.

 

Latest update. They did the pressure test and according to them, the standing PSI should be about 100. Mine is dropping to 25-38 overnight and did the same in a 4 hour period today. They claim this is sure indication that the fuel pump is bad and is the source of my issues. I am not willing to spend 800.00 to test the theory at the dealership but am considering getting something online and installing myself. I haven't checked youtube yet for a video on someone that may have done this already. Anyone taking a fuel pump to task for a 2007 S40? Volvo told me you access from the trunk, its in the top of the tank I think they said.

 

100 psi? No way... should be around 55. I'd have to double check the bleed down specs at work

 

I checked the work order, they only indicate that the fuel pump is not holding pressure. I mistyped above, he told me it was dropping to 25-28 PSI overnight but did tell me 100 psi is where is should be when you first turn the car off. If you could check ES6T, that would be great. I don't know what to believe anymore.

 

It should never be 100 psi. 55 is the spec for the fuel pressure. Unfortunately, I cannot find a spec from Volvo on bleed down pressure, but dropping to 25 overnight doesn't sound bad. The pump acts as the regulator, so if it bleeds down too much then the pump would be the problem. After the car sits, turn the key to position two for a couple seconds and shut it off. Then start the car. That will prime the fuel system and should help and would indicate a likely pump problem.

On the S40, the tank needs to be removed to replace it.

 

Thanks, will give that a try for a couple days and see if that makes any difference. I appreciate your input. It figures the Volvo Mechanic told me that you access the pump from the trunk, and don't have to drop the tank. I guess I will look in the trunk tonight and see if there is an access panel over the tank. My guess, your right and it's gonna be a pain in the butt..

 

VIDA says remove the tank to replace the pump. Also, maximum pressure is listed as 6.5 bar which equates to 94 psi (!). Holy cow, never knew it could go so high. And finally:

"Control
The engine control module (ECM) attempts to maintain a fuel pressure of 480 kPa (absolute pressure). "

480 kPa = ~70 psi which is still high on most things I've worked on.

 

One last thing I read:

By-pass valve
When the injectors are closed because of too high pressure (during engine braking for example) there is a pressure peak. The by-pass valve in the fuel pump (FP) is used to even out the pressure peak. The opening pressure of the valve is approximately 6.5 bar.
The by-pass valve also functions as a non-return valve, ensuring that the fuel pressure in the system is maintained when the engine is switched off.
There is high pressure before the engine is started. This high pressure means that the valve in the by-pass valve opens and the system is "flushed".

 

Absolute pressure is fuel pressure plus air pressure. Relative pressure is the actual amount of pressure in the system, usually around 380 kPa

 

So If I am sitting at 25 PSI in the morning or after the car sits for 4-5 hours, would that be low enough to casue it the turn over but not start? I put a gauge I borrowed from Auto Zone on Saturday and shile at idle it was showing about 80 PSI and stayed about the same when I turned it off. Sunday morning before starting it showed 25 psi and cranked over but would not start. It always starts on the second try. Due to the high cost of the part from Volvo (over 400.00) I will most liekly get a used part off ebay (you can find them for about 70.00) and have my mechanic install for about 200.00. I am just reluctant to spend even this but I can't seem to find anything else that it might be.

 

I've got one at work that isn't going anywhere for a while. I'll see what it drops to.

 

80 psi is way too high. The one I have in the shop is right on at 56 psi. After about an hour and a half, it is at 36.

 

After about 6 hours, I had about 25 psi. The car started right up.

 

I am losing faith that my issue is with the fuel pump. This all started right after Volvo changed the timing belt and hub assembly. Is there any chanace that something they did during that process could contribute to this issue? With the car not throwing any codes, it gives us no path to pursue. I am open to suggestions at this point. I am going to run the pressure test again on Wednesday and see what I get. Any chance it could be the PEM? By the way, thanks for taking the time to work with me on this. I appreciate it.

 

Does the pressure go up when you crank it?

 

Also, did you try turning the ignition key to position II for a couple of seconds before trying to start the car? (this was suggested earlier)