A couple weeks ago I replaced my battery and alternator and then started having intermittent fuel pressure sensor problems so I replaced the fps and now my car cranks but craps out after a few seconds. I decided to put back in the old part because at least my car was running then, but now it still just cranks and craps out after a few seconds. Everywhere I looked, it said the car might stumble slightly after replacing but to let idle, but my car won’t even idle now. Can anyone help me?! Please!!

 

is the car up and running with the original part - albeit poorly? What symptoms or CEL fault codes led you to suspect the FPR in the first place?

 

I had an intermittent engine light come on before replacing battery/alternator and then after it was on constantly. When I scanned codes for alternator, it came up with fuel pressure sensor too, but I forget the specific code. So with that code and the occasional stuttering while driving and the fact that my car just hit 160,000km I figured it was fps and it looked like an easy enough fix.. or so I thought. The car does the same thing with old part back in. It didn’t have any codes this morning but now it won’t even crank and I’m getting electrical warnings like anti skid and alarm system… did I fry my cem or something?!

 

could be a CEM problem - Check out the Xemodex web site as they repair CEMs and have some common symptoms to look for and whether they can do some remote diagnostics. The other thing I'd do is check your system voltage to make sure your alternator is putting out the correct voltage etc. Sometimes after market parts are not 100% compatible and odd results can happen. Did you also replace the voltage regulator or just the alternator? On some Volvo models, its a separate component but on some cars the regulator is built into the alternator.