Dane
FRF Addict
Just finished a big set of upgrades on my 2012 Raptor. These include a Melling oil pump, full Kooks headers, and a 69mm pulley for my Roush supercharger (along with a million misc things along the way). Fired it up, runs great, but we've found one issue. The dash tach consistently reads about 1,500 low. It didn't do this before. I've tried two different tunes, with the same result. I've compared this with the digital tach and my SVC tuner readings (those two look accurate and match each other). So the truck itself knows the proper RPM, and I don't have any codes. Any idea what is going on here? What caused the tach to get out of whack and how do I fix it? I'm leaning away from it being the stepper motor since it actually works and responds fine, it's just like 0 is now negative 1,500.
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