how to check a coolant sensor

[sportpig]

can someone throw a test light on the coolant sensor with the key and tell me if is supposed  ???to have power

[mudkicker715]

No power. resistance

[sportpig]

Ok tell me what i need to do here to see what the problem is

[eaglebeek]

Ok tell me what i need to do here to see what the problem is

OK....take  the wire that was connected to the sender and touch it directly to the engine. Have someone tell you what the temp gauge is doing.

When the wire is touching the block the gauge needle should go all the way to the top.

If the needle moves your sender on the block is bad. If it doesn't move you have a wiring problem or the gauge is bad.

[sportpig]

Alright. ill check back later n get back with ya. thank you

[sportpig]

Well at one point a week ago the needle instantly pegged. now before i trid your idea it was at cold. i turned on ignitio and it bottoms out immediately . i tried you trick and it immediately bottomed out again as it did. i did notice by accident i had a 25 amp fuse i stuck in there instead of a 7.5on accident . il was the same color my bad. did i just flat out destroy the gauge? That's what I'm thinking

[eaglebeek]

Well at one point a week ago the needle instantly pegged. now before i trid your idea it was at cold. i turned on ignitio and it bottoms out immediately . i tried you trick and it immediately bottomed out again as it did. i did notice by accident i had a 25 amp fuse i stuck in there instead of a 7.5on accident . il was the same color my bad. did i just flat out destroy the gauge? That's what I'm thinking

I wouldn't think so. I think that fuse protects the entire dash display...fuel gauge, clock, tach if equipped, etc.

A new sender in the block is not that expensive. I'm still thinking that's what went bad. I know NAPA has it, and I suspect the others have it also. It's not that hard to install, and you don't have to drain the radiator. Have your new sender ready in hand and the threads wrapped with teflon tape or coated with pipe joint compound. Remove the old sensor with a cold engine, immediately insert your new sensor and screw it in.

[carnuck]

That's also the proper way to bleed the air out of your motor if you drain/fill the system or steam pockets will keep forming at the top. Your gauge will also misread if the casting goes down further than the bottom of the sender which traps the air in unless you get your car pointing straight up!

[sportpig]

Well the gauge works. i pulled it out and ran pon neg to it. i tried looking at the wire diagram here and i have a green black wire going to the sensor .  i wired in a new fusr block cause it was melted as . the block came out of a concord so most wires were diff colors. i ended up with 2 beige wires which i connected as well as a snipped green black u found on the pigtail that's on the bottom of the box that has some 2 prong black plastic fuse thing with 2 terminals on it ?

[sportpig]

Fuel gauge seems to be working. I'm going to gas can it up n c if the gauge goes up to verify.

[mudkicker715]

I would doubt that a higher amp fuse has anything to do with your gauges. the sensors are a measure of resistance. nothing to do with voltage. unless somthing unrelated to the original problem happened should be good.