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Old 11-30-2002, 11:26 PM
Arthur Dalton Arthur Dalton is offline
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Join Date: Aug 1999
Location: Florida / N.H.
Posts: 8,784

On the delay systems I have worked on, the basic concept is:

The ECU sends an electrical signal [according to temp and speed sensor parameters for the ECU] to a Delay Switch-over valve. This is a vacuum flow valve that , when electrically energized, opens, allowing intake manifold vac to reach a shift element
[ servo]
at the tranny. Holding vac at this element delays the normal shift point.
So, if we have a delay after the ECU/s parameters have been attained [ warm temp-or rpm speed ] , we may have power going from the ECU to the SOV when not called for .
The simple test--- once warmed up, unplug the electric connector at the SOV and
test drive...If one finds this to be the case , the problem is ecu/sensor related..[ electrical /ecu problem]
The other test is to see if the SOV is ,in fact , allowing vac passage without being powered. This can be checked by simply testing for vac at both sides [inlet/outlet] . Quite possible to have the solinoid/plunger sticking in the open position [ crap/dirt].
This is a mechanical problem.
There is also a possible sticking element/cable at the tranny.
Point being, is the problem electrical, mechanical, sensor, etc. ???
Try these test to isolate the CAUSE , and you will be on your way...
PS -- A good tool to watch these systems workings is a vac gauge "T" hooked to the outlet of the SOV [ between trans/SOV] and the gauge laying on the wiper area [watching gauge through windshield] and a road test.. Knowing how the system works and relating that to what you see on the gauge in real time will tell ....

I am not sure if this is the same on your system, but it may be applicable
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