I found something out tonight on my 82, I have never seen the induction flap open in the hood with the throttle flipped. I was told it would open on full throttle but mine never has. Well I run a 180 deg t-stat and tonight I had to remove the fan to replace the clutch but started it without putting it back on. I paid attention to the temp and never got above the midway mark on the temp gauge. Well while working on the throttle bodies I was working the throttle by hand and opening it full bore and noticed the flap opened... Every time I did it it opened then I realized with the 180 deg. stat it was never reaching optimal temp for the computer to open it. So my question to all 82 owners do you run the stock 195 deg. stat or run it cooler. I also have a aluminum radiator and is very efficient. Just sitting at idle for a long period of time the temp gauge stayed in the middle and finally the electric aux. fan came on. That was without the mechanical fan. I was very happy to see that work. Then it makes me think maybe this is why I get such crapy gas mileage. I've read on here the average is in the low 20s and I checked mine the other day and was 14.9.

 

I've replaced nearly everything minor at least once. Fuel filter twice. 180 thermo. No air pump. Put a new fan clutch and radiator in no problems. Just put a new water pump on - temps even better. Induction seems to be dismantled? Was also surprised to see an electric fan and it work one day. Rebuilt those injectors. Just did another tune up. Two things I watch - rough idle / hesitation ( even slight ) check / replace plug wires. Just went from Accel to Moroso wires. No matter the routing method they find a way to scald or crack. And these copper exhaust manifold gaskets need frequent retorque. Temps don't reach the gauge mid point - even at idle / AC on / 96 degree air temp. Nasty high humid. ( Fl ) Drive twice a week. 14.9 isn't bad unless you are coasting around in overdrive. Foot in it I get 16 to 24. Use 10/40 Mobil 1 high mileage. Fewest drips of any I have tried. New starter, new O2 sensor, new cap / rotor/ plugs ( from Bosch to NGK )/ radiator/ clutch fan/ calipers/ brakes / water pump / thermo / belts/ flowmasters / trans fluid change / fuel filters / accel coil / gaskets / hoses / stuff in boxes like shocks, rear end gasket and oil pan gaskets that I haven't gotten around to. Motor - tranny - rear end all solid. No major drivetrain repairs. I hate to drive it too much but I love to drive it. If that makes any sense. 3000 miles per year. Excellent paint and interior. What was the question ? ha ha ...

 

I have always ran the stock degree thermostat on computer controlled cars. Unless you have a chip/tune to allow a cooler thermostat.

 

The first thing I did with my 82 was buy a brand new water pump (cost $37) and replace the thermostat (there was a 180 Degree unit in there, but it got replaced with another 180 unit) and did other things as well.
The radiator was also new from the PO, my temp is solid, it may approach the the 195 mark on the gauge in very hot traffic, but mostly sits at 180.
My flap door has always worked, and recently I took it off, getting cooler air all of the time and you can feel the difference. Your crappy gas mileage can be a number of different conditions. IMO I don't think the fan has anything to do with your poor mileage.
As you may know I use the 82 as my "dd" and since March of 2012, I have put about 27,000 miles on it, and it runs just fine....

I did have a problem with my exhaust manifold bolts, as 3 of them were entirely loose on the passenger side. So yes, it is a good idea to check them every so often. I have noticed that mine may have a very slight miss, which I have to look into further, but it still gets up and goes, and my top end is nothing short of amazing....I can leave them all behind with just a blink of an eye, when they just get to close to me for my comfort.......

I will disagree with you slightly on that, I would not run anything lower than a 180 or 175 degree stat on a computer controlled vehicle unless you do have a chip, as you stated. But on just about every F-Body vehicle I have owed, I always went down to a lower stat than stock either with or without a chip, and never had any problems. In fact on my 94 Anniv TA the lower stat help with heat soak restarting problems.
The chip in my 82 is the stock chip and I have the 180 stat in there with no complications. Although I do have a Hypertech chip to put in, just haven't gotten around to it.......

 

running a 195* in my '81 with the CCC

 

Well this all started about my fan clutch topic a few days ago. The clutch never dis-engages. Pulled it off and found that it's a HD unit. Will be switching that back to standard. Maybe that's why it ran so cool.

 

Maybe its not as big of a deal on the older systems, but try it on a 2002-2010 ford....it will throw a code for not warming up in the expected time. A slow thermostat will give you the same code. On my 82, with the temp sensor unplugged it will flat flood the engine with fuel. The temp sensor has a direct affect on the fuel called for. Is there enough difference in a 180 vs 195 to throw it off? I don't know myself, but I do know hypertech sells two different chips depending on which stat you run. That's enough proof for me that a stock tune is not optimized for a cooler tstat. Many have run one though with no reported issues.

 

I hear you, can't speak for Ford systems, only have experience with the GM systems.....
The Hypertech Stage 1 is for stock, and exhaust improvements if desired, while the Stage 2 chip is for the "lower" 160 stat usage and other mods.
I haven't unplugged my temp sensor, but I'm sure if it fails it would produce the same result as when you unplugged yours. IMO, I don't feel that there is enough difference between these 2 stats to "throw it off". And I have not encountered any CEL's to date. There are no codes stored in the ECM. Without any traffic and keeping my foot out of it, I have hit a high of 24 + mpg. Usually on my weekly commute I average 19-21 mpg depending on traffic for about 470 miles driven per week.
Having had owned a number of C3's in the past, one of the first things I would do, as mentioned before, is change out the stat to slightly lower than stock. It has always worked out for me and I felt that the vehicle responded somewhat better running cooler than hotter. Those higher temps were basically for emissions than anything else, although that may be and probably is entirely different in today's modern engines.
I have never liked the C3's running near 200 degrees or higher, as that was just to hot for me. Again today's engines are very different, as my SSR & HHR SS that I had, were specifically designed to run at higher temps.

 

I'm curious to see the fuel delivery tables based on the temp sensor readings. Maybe they aren't different enough to notice anything.

 

You know, I would really like to purchase that "TunerPro" cable and get into the ECM and really learn all of that info.....but have to much else to do in the next few months. But that would really be very interesting, that would be a great experience for sure.....

 

only OBDII cars will throw a P0128 code for the wrong thermostat. OBDI and OBD0 will just always run in open loop if the coolant temp is too low.

 

I guess what needs to be know, is exactly at what degree does the ECM determine that the coolant temp is too low? I wonder if that info would be in the Shop Manual?

 

most 82 owners are happy that they have taken off the flap and get cold air all the time.i would check to see what your rpm is at 60 mph.your trans may not be going into overdrive.i would check your tb spray .and check how the plugs look .where is your timing set?have you checked your cat?