I am having trouble starting my 2003 S60 2.4L non-turbo

[Surplify]

So I am having trouble starting my 2003 S60 2.4L non-turbo. My #3 Fuse under the hood keeps blowing (Vacuum Pump/Bifuel DFCO fuse) this started about a month ago after i brought my car into a non-Volvo mechanic who originally said my PVC box was cracked, then said it wasn't and just replaced hoses coming off it. After that he said it wouldn't start again and replaced the Fuel Pump Control Module & said that it had a bad ground wire that he replaced. That is when the fuse started blowing about 10 days after repairs. Now sometimes the car will start and sometimes doesn't -- sometimes tries to start and blows fuse -- other times the fuse blows as I replace it before I even try to start it -- and last but not least sometimes does not blow the fuse and will start and will start and run a days then fuse blows again. Just banging my head trying to figure it out. Anyone have any ideas???

[jonesg]

if he used chinese part thats the first suspect.

is it this ?

[dikidera]

Is your model a bifuel one? If not, then it's likely a short somewhere. The electrical installation on these cars is now over 20 years old and the insulation has cracked is my opinion which is why the fuse blows. I would definitely disconnect the vacuum pump and see how the car behaves that way.

[kcodyjr]

Sounds to me like he pinched part of the wiring harness doing the work, and now it's intermittently shorting to ground.

[abscate]

Sounds to me like he pinched part of the wiring harness doing the work, and now it's intermittently shorting to ground.

That’s on point and highly likely to be the problem.

Fault trace the fused circuit that is failing looking for bad wiring.