Originally posted by Okiebenz
I appreciate the responses to my post. Reference the note from moderator M.B. Doc, my question does indeed have to do with a P1700 Upshift Delay Switchover Valve Control code. I was told that the valve probably was defective since the vacuum line to it was disconnected (at the vacuum source) and it was determined that the "switch would not hold vacuum". The only symptom that I notice is that the "Check Engine" light is on. I do not detect any problem in performance, upshift points, etc. which may only mean that the design of this system is more sensitive or responsive to temperature conditions than I can detect.
REF: 04/03/2002 reply from Moderator STEVEBFL
I have verified that there is 14inHG source vacuum on the input line to the switchover valve. I also have verified that the line to the trans cable servo from the switchover valve will not hold vacuum. Regarding the suggestion of teeing after the switchover to check vacuum existing and holding "until the time interval passes", I assume that is no longer necessary given no holding of vacuum by the servo at the transmission. However, what initiates that time interval, i.e. how can I initiate it and what is that time interval. What is the replaceable/repairable part at the servo and what is the access to it? Thanks. Okiebenz