suicide -- i see you started another thread about odb port w no power, but we're also discussing it here.

Please don't cross post on the same topic -- it just becomes a mess to follow.

Let's keep this thread for discussing the cooling sys issues and the other for discussing the ODBII port.

Thanks

 

Working on today's modern computer controlled cars to me, an old and some what out of date crusty shade tree mechanic is a mixed blessing.
On one hand, they rarely seem to need much in the way of work or maintenance, on the other hand when they do? They proceed to drive you nuts.
And sensor error code diagnostics? Are misleading. In general a sensor with a name rarely does little more than say "This reading is incorrect" and it becomes up to the person doing the diagnosing to try to figure out why.
A MMAP sensor for example reads manifold pressure according to the name. The old school name for that is "Vacuum" and a vacuum gauge indicates inches of vacuum, not pressure.
So one has to think backwards.
Or if you have never used a vacuum gauge, come up with a new way of thinking. And us old school guys, are hard to re-train.
On a car I own the thing would back fire through the manifold and the mmap sensor indicated an over pressure error.
Of course it would, the stupid thing just backfired through the manifold which pressurized it!
And the diagnostics for that is a waste of time. They had nothing to do with the back fire. Which turned out to be a lean mixture backfire caused by a partial plug of the fuel inlet inside the gas tank. That took a long time to finally figure it out.
The point?
For the over heat symptom of the coolant coming out of the tank under the hood which actually acts as both an over flow tank AND the top tank of a radiator that has one.
If for example there is a small hole in that tank that is above the water line, two things are going to take place.
One, no pressure will be developed and on todays engines they depend on a high pressure being held inside the radiator to help raise the boiling temperature of the coolant so it does not develop bubbles which cause the water pump to become inefficient.
This will give on many cars, the Saturn S series included, some form of over heating problem in that as the car gets hotter you will see heat gauge fluctuations out side of normal
And two. When shut down causing a heat spike, the water will expand to the level of the point where the small hole is thus leaking out. Of course the next time the car is driven there is less water, but probably enough to actually pretty much cool the engine but with less of a reserve for various conditions.
Thus the gauge may show wider fluctuations.
To find that on my S series coupe I had to actually remove that tank and look at it and buried where I could not see it? Was a hole rubbed through the side by a screw or a bolt that it had been vibrating on for who knows how many years.
Doorman, and aftermarket supplier of odd ball automotive stuff, actually had a replacement at some what of a discount based on dealer sourced parts. And I have not had a symptom since then.
I'm not saying that is your problem, and you are going to have to pull that tank to look at it. But the symptom was over heating, the diagnostics pointed and an engine problem and the water on the ground made one wonder how it got there, Simply because there is not an over heat tube to drain of the excess water like all my other cars have. And the computer diagnostics were not written to assume the possibility of that stupid plastic tank leaking. And because that tank is remote from the radiator, it is not intuitively obvious that it is pressurized, even when you know it is.
I have owned my Saturn now since 1996 and did not need a means to read the diagnostic codes until a couple of years ago. It took me a while to find something that read them out because the level of soft wear used now is so bloody old.
New Scan tools I looked at stated point blank that they would not work on that year Saturn.
I finally got an old SNAP ON mechanics tool that worked and was no longer needed or used and works on two of my cars.
The Saturn and a FI conversion on a 1980 AMC Spirit.
But my new (purchased in 2007) Chrysler? I still do not have something that reads it out, but it has not been needed either.
Good luck
Hope you find what you are looking for.

 

Derf - Will do.

I will be removing the reservoir coolant tank this evening and inspecting it.

I DID notice that there is only a "Cold Max" level line but no "Hot Max" level line. Does this seem correct?

 

What fuse did you check to fix your slam shifting, suicidecharley? I don't have that problem, but did in an older SC that I had. Maybe it'll help someone else if you tell us which fuse it was.

 

When you take the lid off of that tank, and remember it is functionally part of the radiator so it is pressurized, so not a smart thing to do when the engine is hot, just like a radiator cap. There is a sensor in there that detects when the water level is low thus displaying something on the dashboard to that effect. I don't remember if there is a full indicator on the reservoir but I keep the sensor covered and when you get the silly thing out you can look for one.

 

In the engine compartment there are three 10A fuses horizontally. On the cover they are described as TRS2, TRS3 etc. Those were all blown.

 

Removed the tank yesterday, no holes to speak of, small leaks or otherwise. Put it back on and ran it idling for 30 minutes in the driveway. All operated as expected. I'm hoping the problem may have been air trapped in system and it finally bled out correctly.

 

Thanks for the info. It may come in handy if someone else runs into this.