tbi chevy water temperature sending unit switch

this time i change the water sending unit and switch on a tbi 350 chevy

[@misterb1080]

Nice video. Thanks for the info. I’m going to replace both soon.

[@EfurdGarage]

Thank you. Hope it helps you

[@misterb1080]

@@EfurdGarage it did. Any videos on that era of truck will help me. lol. I have mechanical skills just lack knowledge. Videos like yours put me into a place that I can do the work with confidence

[@EfurdGarage]

@@misterb1080 awesome glad it helped thats why i put them out there. Heck sometimes i use my own videos as reminders 😆

[@irishuwould5185]

My temp gauge is stuck on cold and I replaced the one wire sensor on the side and it still doesn’t work. Should I replace the top one also? I even installed another gauge cluster to see if the gauge itself was broken and the other cluster the gauge didnt work.

[@EfurdGarage]

I would double check the wire first and see if there are any breaks. check the grounds on the intake as well.

[@gusbuster8068]

The sensor on top is the coolant temp sensor. The one on the side is for the temp guage.

[@irishuwould5185]

@@gusbuster8068 ended being I was missing the grounds at the thermostat housing bolt. All works now.

[@CMacHipHop]

Hey man you seem very responsive! My 95 350 will only warm up to about 140° on the gauge and will fluctuate to 150° and back every so often once warmed up. Because of this I idle at about 1200rpm. I’ve replaced the temp sensor and t-stat with ac delco parts. I’ve also already done the water pump, radiator and hoses lately. My fan clutch seems to operate normally. Has some resistance when cold but I still have to try spinning it when warm. Any ideas? Thanks, Chase

[@EfurdGarage]

Have you used anything to verify the temperature? Did a new cap come with the radiator?

[@CMacHipHop]

@@EfurdGarage I aimed an infrared temp gun near the temperature sensor and it read about 195°. I replaced the radiator cap with the new radiator

[@EfurdGarage]

@@CMacHipHop Usually the head runs a bit warmer then that. intake does set around there depending on what thermostat. But the sensor for the computer is on the intake and that one would affect who it runs. the one on the head is just for the gauge. Make sure the grounds are still intact and good. A s long as the one on the intake is good then you have an issue else where, like getting to much fuel, idle air, vacuum leak, timing, o2 etc

[@WillsWheels]

You make it look so easy that even I (a specially trained idiot) could do it...LOL. Sorry about the damage the hail storm caused to all your vehicles. Just horrible....

[@EfurdGarage]

Thanks Will!, you dont give your self enough credit.

[@timdamschroderjr.5100]

My coolant temp gauge kept going straight to 260 after the truck runs for a few minutes. Took the radiator cap off and the coolant was cold. I changed the sensor on the side and it is still doing the same thing.. what should I do?

[@EfurdGarage]

sounds like you have air trapped in the block, bad water pump, or a clog. With the cap off can you see the water moving?

[@DJJDSKREWED]

You got the wrong sensor it fits and plugs in but it’s not the right ohm I’m having the same problem with my 95 gmc you gotta buy the exact ac delco sensor for the exact application you have the 96-99 got a different style connector and 2 wire plug my 95 tbi has a single green wire plug

[@keithrasmussen7071]

We're you ever able to figure it out? Mine does the same thing.

[@DJJDSKREWED]

get the actual ac delco sensor the one you put in is not the right ohm load so its reading way hot when @@keithrasmussen7071

[@dennismorton4688]

thanks for the info and stop laying rubber at end of video haha

[@EfurdGarage]

Your welcome.... Yea i may have heard a few neighbors "ask" me to stop too 😆 wasnt sure though i couldnt hear them in the car

[@goldie_box2904]

I’m sorry for the dumb question. If i wanted to switch from mechanical fans to electric. Would I run the temp wire to the head or to sensor on intake?

[@EfurdGarage]

Well most electric fans i deal with come with a switch you add for the wire, you wont use either of those because it wouldnt send the open current to them like the switch. because the tbi intakes only have the one sensor in the intake and one in the head. its best to leave them alone and buy a dorman 902-2015 housing so you can put the switch in the housing and keep everything where it is. And there are no dumb questions

[@vicentegonzales1795]

Are they both the same sensor or are they both different

[@EfurdGarage]

They are Different

[@jermaine3722]

Hi, I have a 1994 Chevy c1500 350 5.7 tbi and I changed both sensors but every time I plug in the one on the side in the block my temperature gauge rises a little and my truck runs hot but it doesn’t overheat but now I have white smoke coming from the dipstick and crankcase!!! Any suggestions?? Thanks

[@EfurdGarage]

@@jermaine3722 that shouldnt happen. The one in the head on the side is only for the gauge. Intake one controls works with the ecm. Do you have the pvc connected? Used a inferaid thermometer or an after market gauge to confirm temp? How far does it rise?

[@jermaine3722]

Yes, I also changed the Pcv valve and thought that was the problem but to no avail! As far as the temp gauge goes I’m not an expert but it jumps to the very first thick white line on the gauge from the left.

[@RickPreciado]

i replaced the one that goes on the head and i drained all the cooling fluid to see if the temp gauge will go all the way up, and it doesn't, it will only go up to about 190 max, and thats with no coolant at all.

[@EfurdGarage]

well there is no coolant to sense its just some what sensing air at that point. stock thermostat should read about 200-210

[@RickPreciado]

@@EfurdGarage thx for the reply brother. i filled her back up with coolant and the most i can get is 160 tops maybe faulty sensor.

[@EfurdGarage]

@@RickPreciado could be. Or since those trucks are getting so old it could be wiring. What you can do to check is put and aftermarket gauge in and see what ot says and you will know for sure

[@RickPreciado]

@@EfurdGarage thx will do

[@Dave-lg5oz]

Thermostat working properly, heat gun will confirm temps, good luck.

[@SaneCayne]

I have an 87 Squarebody with a 305 TBI. It has idiot lights instead of an actual oil and temp gauge. I have a cluster from a same-year Silverado that does have actual gauges. I've been told I just need to switch out the idiot light sensors on the block for actual gauge ones and the cluster will work. Can I just swap out the "idiot light" switch in the head for a "actual gauge" switch and expect the temp gauge in the Silverado cluster to work? Or would I have to swap the temp sensor at the intake as well?

[@EfurdGarage]

Should only be the one on the head since it goes to the gauge the one on the i take goes back to the ecm

[@EfurdGarage]

But thinking about it. I never seen a sensor specify what gauge it needs. Maybe try just connecting the ither gauges and see if it reads first

[@SaneCayne]

I looked up the "switch" in the head and it's listed as "with light" or "with gauge". So I'm going to buy one that's "with gauge" and give that a whirl.👍 @@EfurdGarage

[@EfurdGarage]

@@SaneCayne yea if thats what it said then thats correct. I maybe confused with the 89 up becuase i dont recall ever having one with an idiot light on those.

[@orlandogomez7542]

Hi, good afternoon, i bought a 95 with a 350, my sending unit sensor There are 2 wires coming from the harness , a blue wire and a green wire, but sensor is only one wire, do you know why is that or where the blue wire goes? Thanks

[@EfurdGarage]

1 wire is for the gauge and it goes on the side of the head on drivers side which i have a video on it

[@orlandogomez7542]

Thanks for the fast response, yes a green wire, but I also have a blue wire coming from the harness , do you know by any chance what that blue wire is used for?

[@EfurdGarage]

@@orlandogomez7542 the one on the side of the head only has one wire fot that sending unit. The temp switch is for the ecm and that one is in the intake it will be a 2 wire.

[@Jordant106_]

There’s an identical plug inbetween cylinders 8&6 on mine ?? But mine is a crate motor supposedly? So maybe they relocated it I’m not sure anyone in the same predicament?

[@EfurdGarage]

It will have the provision on both sides. So someone could have put it there

[@SpicyMcHaggis]

Thanks! Think I have to do it on mine, as the gauge doesn't show anything at all

[@EfurdGarage]

Your welcome Glad it could help. Thanks for watching

[@SpicyMcHaggis]

@@EfurdGarage Thanks!

[@pepemorales8774]

​@@EfurdGarageCan you tell me what color the wire on that bulb is? Or where it comes from, I can't find that cable in my harness.

[@estradamusic9262]

Hello boss, what is the part number for the sensor next to the long tube header?

[@EfurdGarage]

the one that works the gauges on the left. it is a one wire on the head by the headers

[@codymarschinke9383]

So if I put in a aftermarket guage . Can I use the top one?

[@EfurdGarage]

the one wire in the head is gauge, 2 wire is sensor

[@billback4498]

What is the sensor on the back of the head by transmission dipstick on 1994 c1500

[@EfurdGarage]

Can not think of one on the back of the head against the fire wall. only one close is under the distributor and thats oil pressure

[@robertwilson4400]

@@EfurdGarage there is a knock sensor below the oil dipstick but it's in the block

[@EfurdGarage]

@@robertwilson4400 not by a transmission dipstick and not on the back of a head. Knock sensor is front lower just above the pan and

[@ryanbowman3522]

Where did you get that parts?

[@EfurdGarage]

summit racing

[@harleylee5286]

You mentioned one of them controls the fuel which one is that ?

[@EfurdGarage]

The one in the intake. The one in the head is for the gauge

[@codylanzon1020]

Would this make a truck run rich?

[@jamesmedina2119]

​@@codylanzon1020yes it will cause it to run rich