Proper Grounding of CSI Timer Switch Brass Body VERY CRITICAL
Hi guys,
Before throwing away your money and that CSI Timer Switch, please test it per FSM (I have a post on that on my thread, too), and
thoroughly clean the threads on both the brass housing of CSITS and manifold where it screws into.
Can't stress this enough:
Proper Grounding of CSI Timer Switch Brass Body VERY CRITICAL
I cleaned all my temp sensors and the threads on the coolant bypass/intake manifold. As soon as I put everything back together and topped off the coolant, truck went Ta-Da-VROOM!
Details Follow:
After more research I realized that:
1) The CSI timer switch (brown connector) gets its ground from contact of its brass body with the manifold metal. Meaning, the threads on the manifold metal and the CSITW should be bare shiny metal.
2) The ECU temp sender (green connector) must affect starting and cold idle, and finally
3) The BVSV (Bi-metallic/temp-sensitive Vacuum Switching Valve) located on the lower manifold above the CSI Timer Switch and the ECU temp sender, probably also affects cold start and idle. (There has been minimal or no attention to this on discussions about cold-starting.)
So when I flushed my cooling system (and replaced my thermostat with the 2-stage one), I cleaned all the above sensors, and threads where they screw into.
Thirty years worth of scale on BVSV:
Scaled CSITS and ECU temp-sender (CSITS was cleaned earlier to help fix hard starts but I overlooked the threads on the manifold.):
Scaled temp gage sender:
Sensors Cleaned:
Scaled thread on coolant bypass manifold for CSI timer switch :
THIS IS A MUCH-IGNORED DETAIL THAT IS CRITICAL TO PROPERLY GROUNDING THE CSITS.
Here's why:
AND... I did all these in the rain - LOL!
