[666 the legend]

..Aight..Since I cant find a ...3 Pronge temp send for my car..whats the ALTERNATIVE to make it still work and hook up to ..3 pronge female wiring harness..?? Single pronge.?? 2 pronge..??

[Formulabruce]

single, put it in the intake for best results, Ill let the others on here tell you which model to buy,( resistance etc) BUT I will say that temp gauge sensors were originally designed to check the DYNAMIC average water temp before the thermostat. Always use an IR gun on your intake to verfify your sender is in the ballpark.

[666 the legend]

Originally Posted by Formulabruce

single, put it in the intake for best results, Ill let the others on here tell you which model to buy,( resistance etc) BUT I will say that temp gauge sensors were originally designed to check the DYNAMIC average water temp before the thermostat. Always use an IR gun on your intake to verfify your sender is in the ballpark.

Well??I wanna stay with the same location since thats where the wiring harness is....anyone know what the...1..Lead coming out of the 3 pronge harness to USE for a ..Single pronge..??

[murphc4]

I asked the M&H guys about this on a harness I had. I bought the extension harness that goes to the sensor that is mounted in the head on the drivers side for the temp gauge. The extension harness leaves the 3-pronged connector available so that you have both of them hooked up. They said that the 3-pronged sensor was also part of the TCS system. Here is a pic of the extension harness, it looks like the single wire on the bottom is what goes to the other sensor, so that's the one you should use. I haven't received my harness yet, but here is a pic of it from their web site.

[666 the legend]

Originally Posted by murphc4

I asked the M&H guys about this on a harness I had. I bought the extension harness that goes to the sensor that is mounted in the head on the drivers side for the temp gauge. The extension harness leaves the 3-pronged connector available so that you have both of them hooked up. They said that the 3-pronged sensor was also part of the TCS system. Here is a pic of the extension harness, it looks like the single wire on the bottom is what goes to the other sensor, so that's the one you should use. I haven't received my harness yet, but here is a pic of it from their web site.

..Thanks..When yah get the harness could yah tell me where the SINGLE LEAD attaches to the 3..leads..I dont wanna have any extra wires..i want it to look stock..and what SENSOR do you have..??part #..??

[TA455HO]

I have at least two three pronged temp sensors. They look the same as each other. One used and one like new. Any interest in one of them? If so I can post some pctures later.

[666 the legend]

Originally Posted by TA455HO

I have at least two three pronged temp sensors. They look the same as each other. One used and one like new. Any interest in one of them? If so I can post some pctures later.

..Most definitly...

[TA455HO]

As promised here are pictures of the two sensors I have. I'm not sure when I got these, where they came from, how much I paid or what part numbers they are.

I do not have GM boxes for these.

Each one has markings just above the threads.

The NOS one is visually perfect. Markings read AC-85M-220B-253M. Asking $95 shipped to any continental US address.

The used one has some light wrench rash. Markings read AC-95M-230B-253M. Asking $25 shipped to any continental US address.

[666 the legend]

.well..?? Visually it looks to be correct..I sent you a PM...

[666 the legend]

I cant seem to find an old AC part#'s on the NET..though..anyone have a link or somethin..??

[666 the legend]

" The EAGLE has LANDED "..Got the sender today...Thanks alot..

[njsteve]

On the 72's the temp sender is a single terminal, button head, sender mounted on the driver's side cylinder head. This is a different location than was used on the 70 and 71 cars which had them mounted on the intake.

Here is a good thread on the exact temp sender unit you need and some tests I did on the repro units on page 2. Turned out that the $6 Wells #TU5 sender was the best, next to a vintage original sender. The current Delco replacements were completely inaccurate as were the LectricLimited units:

http://forums.maxperformanceinc.com/...ht=temp+sender

The three prong unit is the TCS sender that is on the pass side head. It is not designed or calibrated for the gauge and I doubt it will read correctly since it pretty much functions as a temperature-dependant on-off switch for the TCS system.

By the way, don't use teflon tape as it alters the ground resistance to the cylinder head from the sender.

[666 the legend]

...So..?? Whattayah tryin to say..??

[njsteve]

Originally Posted by 666 the legend

...So..?? Whattayah tryin to say..??

What am I tryin to say is that you seem to be referring to the passenger side location between the 6 and 8 spark plugs (three prong sender) as the temp sender location. It is not. That was the emission control TCS sender location. The temp sender (one terminal) goes in the drivers side cyl head between the 1 and 3 spark plugs.

I was trying to give you info on where to get an accurate, single wire sender unit for less than the price of a cup of coffee, after all the searching I did to find one that didn't falsely tell me my car was overheating when it was barely warmed up.

Do you have the single green wire coming off the alternator wiring section of your engine harness? That is the temp sender lead that goes to the sender between the 1 and 3 spark plugs and feeds the signal to the gauge in the dash.

[666 the legend]

Originally Posted by njsteve

What am I tryin to say is that you seem to be referring to the passenger side location between the 6 and 8 spark plugs (three prong sender) as the temp sender location. It is not. That was the emission control TCS sender location. The temp sender (one terminal) goes in the drivers side cyl head between the 1 and 3 spark plugs.

I was trying to give you info on where to get an accurate, single wire sender unit for less than the price of a cup of coffee, after all the searching I did to find one that didn't falsely tell me my car was overheating when it was barely warmed up.

Do you have the single green wire coming off the alternator wiring section of your engine harness? That is the temp sender lead that goes to the sender between the 1 and 3 spark plugs and feeds the signal to the gauge in the dash.

..Oh okay..I will have to look at my harness for that wire..later on today..These cars are Complicated...lol..

[666 the legend]

Just curious?? iwas on e-bay and found this TEMP SEND that said it was for cars with GAUGES ONLY and is good for 70-78..? or somethin like that..Will this work..If not..Whats the one at AUTOZONE you were talkin bout..?? Part #..?? or just ask the idiots behind the counter for TEMP SEND for a 72 Pontiac..??

[njsteve]

Ask them for a Wells part number TU-5. That is the correct sender. The ones on eBay are pretty much all the same incorrectly calibrated "one size fits all" pieces of crap they sell to enthusiasts thinking we will never know the difference. But once you install them and then see your gauge reading 210 when it is actually 170 degrees water temperature, you will get as mad as the rest of us.

The Wells TU5 is the most accurate one I tested other than finding a vintage 1970s Delco sender. Stay away from the newer Delco senders as they are completely inaccurate. See here: http://www.sssacc.org/Tips/Temperature_Sending_Unit.doc.
Or here (where they used my chart!). http://www.camaros.net/forums/showthread.php?p=1486927

It seems like all the modern produced senders other than Wells are made by the same company who has the resistance settings all wrong, leading to the too-high temp gauge syndrome.

[666 the legend]

..WELLS TU-5 it is then.....Thanks alot steve.....I like learning from your MISTAKES...lol.......seriously though..Thanks..

[666 the legend]

..Thanks steve..SENDER is now installed...Now? I noticed in this pic? to the left there is a WIRE mounted to the head..?? Is that a ground coming from that same ALT harness..??

[njsteve]

That is the neg battery cable mounted to the head bolt/stud.