Active temp gauge

[sixt9coug]

I was driving the 94 today and it dawned on me that the temp gauge on this car is really, really active. I am used to my Ranger and my Mom's 02 Mustang where once the car is warm, the gauge really doesn't move at all. The 94 however will read anywhere from the O in Normal, to the M. I noticed today after flooring it on the freeway for a few seconds (2.73s.... I have TIME to floor it and look around) the temp 'spiked' to the M before coming back down to just under half way. I don't think anything is running hot, but I am just curious. Does everyone else have this happen in their car? Is it normal for it to move around that much?

I guess it could be worse... my Mom used to have a 96 V6 car that would damn near hit the L before the fan came on. That car would mysteriously eat coolant too. It just had over 50K original miles on it too when I wrecked it. (yeah im bad)

Oh yeah.... as long as I have your attention... are the needles supposed to be a darker orange than right here? (you can SEE the 2.73s working!)

 

[Chythar]

The needles seem to vary in color from car to car, from yellow to a dark orange. So that's not a worry. As to the temp gauge, there are two sensors that measure temperature on our engines:

ECT (Engine Control Temperature): Used by the computer to determine coolant temp. Screwed into the metal tube on the passenger side of the engine.
CTS: (Coolant Temp Sender): Used to feed the gauge in the cluster. Screwed into the intake next to the distributor on the right side.

These two sensors are exclusive, meaning that the computer knows nothing about the ECT, and the dash gauge only reads the CTS. You could have a bad ECT, a bad CTS, a bad gauge, or something else wrong with your coolant system. Your first step is to find out if the gauge is accurately reporting coolant temperature. To do this, you need to find out what each sensor is reading to know where the fault is. The first step is to get the ECT reading. If you have a code reader that reads PIDs (engine sensors, basically), you can read what temp the ECT says. When you have the ECT reading, you can compare it to the gauge and see if they seem to match.

 

[tmacie]

The needles seem to vary in color from car to car, from yellow to a dark orange. So that's not a worry. As to the temp gauge, there are two sensors that measure temperature on our engines:

ECT (Engine Control Temperature): Used by the computer to determine coolant temp. Screwed into the metal tube on the passenger side of the engine.
CTS: (Coolant Temp Sender): Used to feed the gauge in the cluster. Screwed into the intake next to the distributor on the right side.

These two sensors are exclusive, meaning that the computer knows nothing about the CTS, and the dash gauge only reads the CTS. You could have a bad ECT, a bad CTS, a bad gauge, or something else wrong with your coolant system. Your first step is to find out if the gauge is accurately reporting coolant temperature. To do this, you need to find out what each sensor is reading to know where the fault is. The first step is to get the ECT reading. If you have a code reader that reads PIDs (engine sensors, basically), you can read what temp the ECT says. When you have the ECT reading, you can compare it to the gauge and see if they seem to match.

Fixed

 

[ProKiller]

the stock gauge is horribly inaccurate. until you actually know what the temperature of the engine is with a true gauge then your just spinning your tires. i would go about chythar's route.

 

[sixt9coug]

The needles seem to vary in color from car to car, from yellow to a dark orange. So that's not a worry. As to the temp gauge, there are two sensors that measure temperature on our engines:

ECT (Engine Control Temperature): Used by the computer to determine coolant temp. Screwed into the metal tube on the passenger side of the engine.
CTS: (Coolant Temp Sender): Used to feed the gauge in the cluster. Screwed into the intake next to the distributor on the right side.

These two sensors are exclusive, meaning that the computer knows nothing about the ECT, and the dash gauge only reads the CTS. You could have a bad ECT, a bad CTS, a bad gauge, or something else wrong with your coolant system. Your first step is to find out if the gauge is accurately reporting coolant temperature. To do this, you need to find out what each sensor is reading to know where the fault is. The first step is to get the ECT reading. If you have a code reader that reads PIDs (engine sensors, basically), you can read what temp the ECT says. When you have the ECT reading, you can compare it to the gauge and see if they seem to match.

Thanks, I will try that. A friend of mine has a Snap-On scanner that does live readings of all sorts of sensors.

I was coming home today when I decided to floor it getting on the freeway. When I first got going, I was right at the R on the gauge. After I got off of the gas (floored it through 1st, 2nd and lifted after I got into 3rd) the gauge spiked to the A. Sooooo yeah I am starting to wonder if the gauge is right. It stayed there for less than a minute before coming back down and even dropping to the O during the rest of the 3 mile drive home. So either the cooling system can both rise and fall rather quickly, or I have something reading wrong or just in an exaggerated fashion.

Any other possible causes if it indeed is a cooling problem? Cavitation in the pump possibly? I don't hear any pinging and IIRC, the timing is around 10btc or so. I only ever have gotten the temp gauge past half way after wringing it out in the higher rpm range like the above scenario. Other than that the gauge tells me the car runs pretty cool.