Just put it in new engine and went to start it up,and I have no 12v at main wire to diz,checked it with a test light key on,nothing I never changed anything,just put car back to stock Did I miss something that I unplugged
also the crazy temp gauge is pegged hot I replaced all 3 sensors when I put motor in,thought that would do it Any ides wher I need to go from here thanks

 

Probably. What car? What motor? What ignition system?

Temp gauge pegged = its wire shorted to ground, most likely

 

Thanks I found it,car is running,tapped on gauge and it came back down ..it works somewhat but dont read true already replaced sensor between 1-3 cut
now I can't keep it from boiling gets hot after3 4mins and I can feel the coolant when I grab the hose bubbling its a reman engine new water pump even put a restrictor in place of thermos just in case Only thing not done is rad

 

Very common for the temp needle to spaz and get physically stuck against the inside of the gauge housing when you turn the key on. I glued some pegs to the face of my gauge to limit travel of the needle. My temperature gauge is very inaccurate too.

 

Does your car have the air dam beneath the radiator in place?

Use a $30 infrared thermometer to measure temperature of top radiator hose, and report what temperature the fan kicks on.

 

Just noticed you list your car as a Chevelle.

I’ll point out that this is a forum for third gen Camaro and Firebird.

 

I do have a chevelle but I also have a 84 z28 I'm working on now .And I installed a temp gauge in the thermostat housing and the fan came on at 180 .I drove it to gas station and it didnt get over 180. I guess i will just install a aftermarket gauge just to b sure as mine seems to b reading cooler .I also bought a new rad and 180 thermostat

 

It does have the air dam