Is there a thermostat in it??

 

As far as I know, there is... have been looking up parts, etc. I'm reading/hearing the issue could be 1) the thermostat, 2) the sensor, or 3) the gauge itself... possibly a combination. Thoughts? Thanks.

 

If you can, plug in a scanner, and see what temp the PCM thinks the engine is.

Or, pick up one of the InfraRed thermometers, point it at the thermostat housing when the engine *should* be fully warmed up. See what temp it really is.

Or, pull the housing, see if the thermostat is really there, and test it. See what temp it starts opening at.

 

'84 will just have the brain box, not a computer. It will be electronic ignition. Computers didn't really come around until '88 or so with fuel injection.

 

Valid point. To used to working on the newer stuff........

 

Thanks. Is there a standard temp it should be opening up at?

 

I *think* it should be around 195.......

 

Standard OEM is 195. You can run a cooler one as you don't have fuel injection but winter heat will suffer. I'm old. I still count battery caps to see what voltage I'm working with. 3,4, or 6.

 

My van had the wrong sender installed when I got it. It should have had a gauge sender but it actually had a warning light sender so the gauge almost never moved. Also, if it has one of those fail-open senders it could be stuck open. I had one do that leaving Louisiana...it never boiled but it got hot enough to stick the thing open.

 

If you mean the fail-safe thermostats, every single one of those I've put in failed not long after. I've worked on several vehicles that never made any heat in the winter and those had failed fail-safe units too. I go with a regular old style thermostat. I drill a 1/64 hole in the plate and slap it in.