My 99 s70 is having a problem staying started. It will start, run 5 seconds or so then will sputter and die. If you try to restart immediately it will only sputter and will not run. If you wait a few minutes and try again it will repeat the earlier behavior of running for a few seconds then dying. I can not hear the fuel pump but I am by myself in a parking lot and have to one to listen at the trunk. I guess I am hearing the pump relay click at least whrn I turn on the ignition. The only other thing I am noticing immediately is the idle air controller on is vibrating (like a hum)wether or not the ignition is on unless i unplug it which I dont know if that is normal or not.

 

Lots of stuff makes noise when you turn on the ignition switch; not just the fuel pump relay. I've read lots of fuel pump relay problems. I think some people keep a spare in the glove box.

It sounds like a fuel delivery since it starts. The cheaper option is the relay compared to the fuel pump itself.

You could also have a dirty fuel filter though i have never had pone cause a car to run badly - but I also do replace them once in a blue moon.

Your fuel rail pressure regulator could be bad as well. You'd have to test pressure before the regulator.

There is a shreder valve onthe fuel rail. You test fuel rail pressure there. When yo utest the pressure, make sure you test the pressure before the car starts AND after it starts. I've had a fuel pump that could make pressure but could not keep up with fuel demand after the car starts.

 

I hadnt seen your post yet but I did see Roberts youtube video for testing out the relay with a jumper and went ahead and did that. It was in fact the relay. I went down to the salvage yard and pulled a few of them ($5 bucks each why not) and went back and popped it on. Fixed it right up. I think this was also causing my fuel economy problems. The car has been running kinda crappy at idle and now it runs very smooth. Time will tell.

As a bonus, while i was at the salvage yard i found two VERY nice front leather seats in a V70 that match mine. $25 a piece woot! My drivers seat is in pretty crappy condition (several big holes) and I have been looking since I bought the car a few months ago for a better one. It feels like providence. I grabbed the passenger seat as well because it was in freakin perfect condition. Looks like no one has sat in it.

Thanks for the reply though kwatt!

 

Hurrah! Nice grab on the seats as well.