temp problem

I recently replaced my intake gasket on my 98 silverado with a 350 in it. ever since the temp gauge in the dash shows its running hot. It will show about 230 when the thermostat hasnt even opened yet, i have replaced thermostats and temp sending unit to the gauges. Ive got good heat in the truck. just wondering if maybe a missed a ground or something else,I would love to hear anyones opinion on the matter

I recently replaced my intake gasket on my 98 silverado with a 350 in it. ever since the temp gauge in the dash shows its running hot. It will show about 230 when the thermostat hasnt even opened yet, i have replaced thermostats and temp sending unit to the gauges. Ive got good heat in the truck. just wondering if maybe a missed a ground or something else,I would love to hear anyones opinion on the matter

measure the resistance of the sender output..@ 230deg f then reply with the reading..

since you removed/replaced the old one measure the resistance when placed in a pot of boiling water ....