1990 jimmy digital dash,temp reads 200+

[dub1620]

i am wondering if my jimmy is running hot or if i am worried for no reason. It has a only 100, 200, and 260 with the red line two bars from the 260 mark. my car usually runs right at the two hundred mark, but sometimes on the freeway mostly it will jump up past the 200 mark. i think the running temp for my engine is 195 degrees. which wuold mean probably no problem at the two hundred mark, but when the next bar lights up it concerns me, i just would like to know if this is normal, or i should get something checked out.

[old_master]

A 195 thermostat will begin to open at 195 degrees, which means engine operating temperature can/will vary above that. The most accurate means of measuring engine operating temperature is with an infra-red thermometer with it's beam directed at the thermostat housing. Compare the reading to your dash guage, if the two are significantly different, replace the coolant temperature sending unit located in the cylinder head. Then retest, if the dash guage is still incorrect, the dash unit needs replacement.

[dub1620]

is my temp sending unit on the left side of my block between my exhaust manifold sections? how hard to replace? thanks for the info.

[old_master]

Originally Posted by dub1620

is my temp sending unit on the left side of my block between my exhaust manifold sections? how hard to replace? thanks for the info.

Yes, that's it. The auto parts store will need to know that the sender is for the digital dash, not the onboard engine computer. Drain the radiator, disconnect the electrical connector and unscrew the sender. Before you install the replacement, wrap the threads with teflon tape, (some new senders already have it). It's not a difficult job.