cold start injector problems 87 4kq

[Luke Rickert]

I have been trying to figure out why my car isn't running very well these days. It is hard to start and runs badly when it does particularly when cold, today I figured out that cold start injector isn't getting triggered. The thermo time switch (the one on top of the upper coolant flange) is a year and a half old, so although it might be the problem it shouldn't be too suspect. The injector will fire when the G/W side is jumped to ground and the ignition is on, so the power in (R/B power circuit is OK) It was also tested on a cold engine, after sitting in an ice bath. (the air temp is under 70)

On page 97.269 in Bently manual it shows a G/W and a R/BK wire coming into the injector, from the Thermo Time Switch. But on my car the wires are different colors at the thermo switch (Bl/BR and what looks like light blue/yellow) The wiring harness does not appear to have been modified in any way. From the diagram it looks like there should be continuity between the G/W wire at the plugs at the injector and the sensor? But there is no connection between them.

Any ideas? should I get a new temp/switch, jump the wire from the sensor to the injector or am I totally mis-reading this diagram?

also can anyone explain how this thermo switch works? my reading is that it G/W wire should be grounded by the switch when it is cold and that the R/BK wire only has power when the car is started. Should the switch have a ground through from one of the terminals?

thanks

Luke



Luke Rickert
Sent by Mail at easy.com, an easyGroup company.