i've got an 85 IROC 305 tuned port and the temp guage in the dash quit working in the dash so i bought a manual aftermarket guage to put on it temporarily and when i went to put the sender for the new guage in the intake i found that their is two senders for this car one for the computer and one for the guage and they both have two wires ran to them so i was wondering if someone on here could shed a little light on this for me because i have no idea which one is which, the guy at the parts store told me it was the one with one wire well they both have two wires and then he told me it was the one with the oval plug so i looked and one has an oval plug and the other one has a big square plug but i didn't want to just take his word for it since he told me wrong the first time does anyone know for sure which one it is or a way i can check it

 

i had the same problem with my 86, and i was told to remove the lower sending unit. however, i later found out that one is for the cold start injector, so my car wouldnt start below 30 degrees without ether. the larger sendit unit is for the ecm. i cant find where find anything in my haynes manual on its location, but it might be on the side of the head. i threw out my engine a while ago, so i dont have anything to really look at.

 

both of them are side by side on the front of the intake the only difference is the size of the gromet and the shape of the plug

 

Look on the side of the head, usually the drivers side, and see if you don't see a sending unit there. Those ones that have two wires are control sensors (in and out directed by temperature). For the gauge, it's a sending unit, and yours should have a flat spade with one wire connected to it.

 

theirs nothing on the head at all that i can find

 

atlast i found it it was right where you told me it would be camaro 69 i would have never seen it but as i was checking for a second time on the head i just happened to see a single wire with a spade connector on the end just hanging down not hooked to anything beside the head so i got out the jack and jacked up to see if i could see it from the bottom and sure enough there it was but you cant see it from the top its right under the exhaust manifold towards the front of the head on the drivers side and it was in fact disconnected so i hooked it back up and its out there running right now to see if the guage in the dash works.

thanks for the help i would have probably never found it by myself because i was looking in the wrong place

 

did it work?