Failed MD emissions code P1537 2002 ranger. How to fix to pass emissions test

 

Welcome to FTE.
P1537 = Intake Manifold Runner Control (IMRC) stuck open.
Try a forum search on the IMRC, or the trouble code number you posted, as there are several threads covering problems with the IMRC, or its controls. Some are operational vacuum problems, some are rust problems binding it up. Keep us posted on your trouble shoot/findings. EDIT: Example of a IMRC thread, https://www.ford-trucks.com/forums/1...pen-p1537.html

 

Had same issue with mine. Dealer found a TSB that called for a reflash of computer. The IMRC is designed to kick in only at certain RPM. If most of your driving doesn't fall into that RPM range to engage it, when it suddenly does it has a tendency to stick. The reflash engages it at a lower RPM which puts it into use on a regular basis eliminating the sticking. Haven't had an occurrence since. Mechanic I deal with at dealership knows his stuff and tried swapping out vacuum control with no improvement while troubleshooting and after much digging found the TSB.