I want to ask if the code p1631 is always because the security system is blocking fuel entering the fuel nozzles
My car has 100000 miles.
My car has a manual transmission.
Hello - the P1631, if this is for a Ford Transit van as it appears, is most often a byproduct of a poor battery condition, with multiple cranking events before a successful start. I would check first for low starting voltage (while cranking). Resting voltage won’t tell you what you need to know. For assistance, I recommmend a hard starting inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs. If battery condition is satisfactory - the P1631 code is, as you question, a problem with the security system (key problem).
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