Tachometer and Temperature Gauge Questions

[gcjustin]

Ok, two questions for you guys, if you would not mind helping me to diagnose.
1. Since I have owned the car, the tach doesn't read any rpm's, it just sits at 0 the whole time and the MPG gauge goes from the far left to the far right when I start the engine. I have replaced all of the gauges with good ones from Oklahoma Foreign, so I don't think it is a gauge problem.

2. I haven't noticed it until recently, but, whenever I drive on the freeway for extended amounts of time, the temp gauge will peg itself at the top and not come down to normal temps for an undiscernable(sp?) amount of time. The car itself doesn't seem like it is getting that hot and both the fans kick on.

If you can help me out, any help would be greatly appreciated.

Thanks in advance,
Justin Browning
1987 944na

[AFJuvat]

If you have replaced your gauge already, it is probably your wiring. Make sure the instrument panel is connected properly, all of the grounds have good contact, and the wires to the coil are clean and connected properly.

Both fans shouldn't kick on unless you have the AC on.

Again, I would venture to guess an electrical problem in your instrument panel.

I would also flush, replace, and bleed your coolant just to be sure....

AFJuvat

[Nipzz]

I have a 85 1/2 944 and both of my fans kick on when it get hot. I dont have my AC on. im not sure if it just the year or what but i know my fans trun on.

gcjustin, when it over heat on the freeway, one reason it might do that is because of low RPM. if you RPM is low the coolent does not circulate though as well. try droping it a gear for a couple of min or rev it a bit. that just what i have noticed on my long drives.

[97XRAY]

I have an early (83) NA and both the fans should in fact kick on when the car gets hot - and they do. The smaller fan stays on after the engine is shut down, whereas the larger fan runs only while the car is running and hot.
Which raises the question:
Without AC on, why does the larger fan reduce idle RPM - is it still running off the engine??? Odd isn't it?

[gcjustin]

Thanks for the info guys!!
I will try the higher rpm thing on my way to work today, if the temp gauge gets up that high. I guess that the high 80's and low 90's aren't helping the cooling at all either.
Justin