OK, so our 9240 DL project is coming along nicely but is still stalling after we start it once it warms up it will stay running but idles rough and dies under power. Wanted to try to test the map sensor or change it out. Can’t find anything in my Chiltons about a location or if my car even has one, but the part store list one and has a pic for one. I am a little baffled by it. Can anyone help out? Thanks in advance.... OK just did what I should’ve done in the first place and looked in the popular questions section. Going to finish my lunch and then go try and find it🤷🏻‍♂️

 

check out volvotips.com to see if they have anything. Not sure if the MAP (aka barometric pressure sensor) would not be on my suspect list - sounds more like an intake air leak. Does it idle correctly before it warms up?

 

I don't believe Bosch equipped cars have MAPs, and all 240 are Bosch... The Regina cars, non turbo 740/940 have MAPs. It's a sensor that plugs into the intake hose right after the air cleaner (on Regina cars).

 

no it doesn’t. Sprayed carb cleaner all over engine bay and intake but no difference ? When you first start it, runs for 5 sec or so and then chugs out. Does that three to four times then it’ll catch and stay running But goes up and down to almost shutting off. If you hit the gas and rev it a little it will smooth out a little bit still not running smooth. Revs fine with not much hesitation. But if you shut it off and restart it, chugs and carries on like before 🤷🏻‍♂️

 

have you tested fuel pressure? Could be low. Before doing a cold start, try jumpering the fuel pump relay (this will engage the pump ) to let it build pressure for a few seconds then go and try starting the car. If that helps, you probably need a new fuel pump.

 

The main fuel pump? Or the one in the tank.

 

these cars will run just fine with a dead in-tank pump as long as there's at least 1/3rd a tank of gas... diong that will make the main pump work harder, and sound noisier, and i'm sure its not good for it. the tank pumps job is to keep the main pump from vapor locking.


another factor, on the output side of the main pump is a anti-return valve, who's function is to hold fuel pressure even after the pump stops that valve being bad can cause hard starting.