I have an 86 gt, its running fine, but it seems a tad on the cold blooded side. I can let the car war up for 20 minutes and it will hit about 220 then as soon as i drive it goes back to about 180. I'm running a stock fan switch and thermostat. I get solid heat, but i can see at a stoplight that the car idles at 1200 rpm instead of its usual rock solid 1k rpm. I did have the water pump and all hoses replaced, but i doubt that that would be the problem. The cts is new and fixed my idle hunt problem. I am thinking the new thermostat 195 deg i put in about 1 1/2 months ago is opening way too soon. Any ideas?

Sounds like your cooling system in great shape. I am not familiar with the 2.8 but isn't 195 degree thermostat stock?

Jim

[This message has been edited by FieroJimm (edited 10-22-2008).]

ive got a duke and ive got no thermostat in it..lol
i stay below 120 on the dash but i think my temp sensor is bad

I would not count on the gauge for an accurate temp reading. Think of it as a trend analysis. For an accurate reading get WINaldl and look at what the CTS is reporting to the ECM.

The stock fan switch comes on rather high. Mine came on at 228* as reported by WINaldl.

The first big quarter "tick mark" on the temp gauge is 190, not 180. Your engine temp is normal, if you're having high idle, spray some carb cleaner around your EGR tube and listen for a difference.

sounds like your cooling system is fine. if i leave mine at idle for a long tim 20 to 30 minutes it reaches 220 and as soon as i get on the road it goes down. the temp guage is not accurate at all.

Ah it sounds like its normal then. I was going dam that is a wide range in temp shift. I forgot how inaccurate the stock temp gauge is. Where can i get the necessary equipment /software to run a winald scan on the computer? I did check the egr mines been deleted and both plates that block the openings are closed up fine. Thanks all for the help.

Get the free software here: http://winaldl.joby.se/

You can buy an ALDL cable from folks here (Dodgerunner?)

or from one of the stores online: http://www.aldlcable.com/

Or make your own for cheap: http://couleefiero.tripod.com/ALDL.htm

There have been some issues with USB equipped laptops not working correctly. I use an old serial port laptop with no issues.

quote Originally posted by Dash: ive got a duke and ive got no thermostat in it..lol i stay below 120 on the dash but i think my temp sensor is bad

I got 31 mpg without the thermostat. I jumped up to 34-35 with a 180*, and 39-40 MPG with a 195* Dukes ECM like it hot.

Below is an example of a AldlView plot for my Formula, covering about 12 miles / 20 minutes of driving. Note that I did this run because my temperature gauge on the dash was wagging around quite a bit and generally indicating that the engine was running cooler than normal:



The yellow trace is road speed, which ranged from zero to 63 mph. The red trace is the Coolant Temperature Sensor, which ranged from 71 F at startup to a peak of 203 F. This is with a stock 195 degree thermostat, and an ambient temperature of 71 F. The coolant temperature was a lot more stable than I had expected (only +/- 6 degrees once fully warmed up), over a wide range of driving conditions, from stop and go traffic on urban streets (4.7 miles), to a few minutes of sustained expressway driving (4.6 miles), and back to local streets (2.6 miles).

There's no substitute for your own test data. It's sometimes the only way to know what's really going on.

[This message has been edited by Marvin McInnis (edited 10-23-2008).]

I appreciate the help, I'm going to get the cable and the software and run it, and see what i can see.