2002 SL2 Idles Hot

when stopped at a red light or in traffic the temperature gauge goes from slightly over 1/4 to past 1/2. Once the car gets moving again, the temperature goes back to normal. (I've never just let it sit for ten minutes or so to see if the temperature will keep climbing.)
According to the Saturn dealership I called, this is normal, but I wanted to check to see if anyone else had noticed this.
Joseph
Reply to
Joseph Bloch
short version: They are correct
longer version: ...this is what I wrote in a recent thread:
"it is actually normal for the engine temperature to go up _some_ when you're in city traffic, as compared to highway driving. Two reasons for this include a) you're not pushing volumes of air past the radiator b) you're working the engine harder in stop/go traffic, ie at a steady 65MPH you're probably holding somewhere around 3000RPMs (DOHC). In city driving you're constantly going from ~1000 to 4500 (or so, depending on MT or AT) under load."
one other reason that I didn't mention there is also that the water pump isn't moving as much coolant - since the water pump's flow rate is directly related to the engine RPM.
It is NOT normal for the temperature to go past 1/2, then go past 3/4 and just keep going up - all the while with the cooling fan never coming on. When the fan does come on, you should notice a fairly rapid drop on the gauge. Keep in mind tho the cooling fan doesn't respond to the gauge - there is a seperate sensor which goes to the computer which decides when the fan should come on. The fan will also not come on over a certain speed (MPH) because running the fan at speed tends to block more air than it can push across the cooling fins.
-rj 98SL2
Reply to
richard hornsby
snipped-for-privacy@surveyusa.com (Joseph Bloch) typed until their fingers bled, and came up with:
The temp guage in your Saturn (and all S-series - not sure about the ION,VUE, or L-series) shows a much SMALLER range than "normal" guages. Normal driving temp should be around 1/4 on the guage - 96+ seem to read a bit higher, 91-95 a bit lower, in my experience. The red mark on the guage marks the upper end of the "normal" temp range, NOT an overheating condition. The fan should kick on when the guage reads 3/4.
Reply to
Kevin M. Keller
No ... it is not normal. What I should say is that is should not be that way. But, if you leaven your airconditioning off and do not add an additive to your oil ... then it will happen. First, when you stop on a hot day ... you want to have the airconditioning ON ... that will cause the fan to kick on and keep your engine cool. Next, Add something like DuraLube to your engine a litte each oil change and it will never climb ... it will stay just over the 1/4 mark. Roy, snipped-for-privacy@aol.com
Reply to
ProfWdesk1
erm, huh? oil additives to keep the engine cooler overall? It is suggested that oil additives are not only generally useless, but may be more harmful than helpful because they can interfere with the designed composition of the oil itself.
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In any case, when you turn on the A/C, you're forcing the engine to work harder to run the compressor and generating heat from the compression/cooling process. This is why the fan comes on - to compensate. At best, on a hot day, you're offsetting the work of the fan by adding more heat to the system.
The fan will come on automatically when needed. You do (should) not have to force the fan to come on, unless there is something wrong with ie, the temp sensor and the fan never comes on. In the SLs (at least), the behavior as described by jbloch is normal.
-rj 98SL2
btw, the case with the FTC seems to have been resolved in 2000, but it is mostly lawyer-ese which I can't understand:
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Reply to
richard hornsby
Also, there seem to be a question regularly about oil temperature ... which, the basic way to solve that is to keep the airconditioner on and have some kind of oil additive.
Reply to
ProfWdesk1
Did you read anything I wrote? Your suggestion might be "the basic way" but it is not the correct way, and is fundamentally flawed in its logic.
I'll repeat myself for the hard of hearing: Turning on the A/C creates additional heat from A) running the engine harder and B) the heat exchange process of the compressor. The cooling fan will come on when the PCM finds it is nessecary.
Also, did you miss where the Federal Trade Commission found that the advertising claims of the oil additives were bunk?
If the engine is overheating and there is enough coolant flowing, you can reduce the engine temperature some by turning on the heater full blast (not the defroster - in some vehicle makes this runs the compressor). If you are venting or don't have any coolant, this won't help.
If you're really bent on running the cooling fan at will, you would be far better served by wiring an override switch to the relay. _However_, the original question asked if the behavior described was normal. My response stands: affirmative.
-rj 98SL2
Reply to
richard hornsby
In article , snipped-for-privacy@surveyusa.com says...
This just came to me... Not sure if this applies to your year or make and I never looked this up but when looking at a fuse box under the hood of a saturn I recalled seeing 2 fan relays. One said high, the other said low. Maybe the high speed fan relay is bad. Again, I do not have a wiring diagram on hand but this is something to look into. Anyone out there with a book or GM SI disk or something able to referance a 02 SL2?
Reply to
Blah blah
i had a similar issue with my '97 sl2. the fan motor was bad. on the 97, the A/C relay and the fan relay were the same part number, so i switched them out in order to narrow things down.
nanook
Reply to
nanook
The sounds good. But, what is logical is often wrong. The key is to keep the engine temperature down and those two basic ways (leaving air conditioner on so the fan runs and add an oil additive ... specifically Duralube or probably STP) will keep the tempurate less than the temperature the PCM decides is about to ruin the engine.
Reply to
ProfWdesk1
snipped-for-privacy@aol.com (ProfWdesk1) typed until their fingers bled, and came up with:
The key is to
Actually, just turning the A/C on, and then off again after a few seconds will cause the cooling fan to run for 2 minutes.
Reply to
Kevin M. Keller

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