When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
have a 97 aerostar engine started to shutter couplle days ago so i through it on the diagnostics and gave me the code p1390 wich is P1390 Octane Adjust out of Self-Test Range where would i find this sensor and what can i do to fix this problem thanks
It sounds to me like one ot two things: (1) Someone may have pulled the Octane Adjust Shorting Bar on your truck. When this is done, it's usually to help keep excessive spark knock (pinging) under control, or (2) You have a problem with that circuit, like for example, a short or open caused by a chafed or broken wire or a corroded connector.
Ford manual says:
P1390 - Octane Adjust (OCTADJ) "The octane adjust is software activated in the powertrain control module, used to retard spark timing by three degrees. The hardware shorting bar has been removed."