Just like the thread says. I was running a 3 bar custom Speed density OS. I got a 2 bar map sensor, wired it in place of the 3 bar. Confirmed the pinout was correct. The truck fired up, but ran extremely poor. I did some work with to the VE table. But the truck got the point of not even staying running at all. So I after much frustration and going nowhere with it, I decided to revert back to 3 bar with the MAP sensor I was using before, (thinking it could be a bad 2 bar sensor.)... The Truck has yet to start and stay running for more than 1 second. It sputters and dies like the fueling is way off. I noticed my Boost controller reading the Max psi at key on engine off, when it used to read either 0 or 1 psi.
I figured this could be a short or an open circuit between the MAP, PCM and the boost controller somewhere, but after checking the wiring countless times, I'm confident my wiring is not the issue. The scanner reads 105 KPA with KOEO. Pretty sure it used to read about 101kpa in 3 bar. When the truck tries to fire the cells that populate seem to be the lowest KPA cells on the chart. This is surely MAP related causing the fueling to be in another dimension. I have updated the scanner to show the correct MAP sensor each time. I even reverted back to an older 3 bar tune, but to no avail. I noticed after the engine dies, I can hear the fuel pump re-priming itself. Is it possible that something could have gone arai when converting the OS? I have done custom OS w/ HPT on about a dozen vehicles over the years and never had any issues. This one has me stumped.
Maybe I am missing something here? Any Ideas on what I should try?