Car does not start only when hot (i.e. say after driving 15 or more minutes), will start fine again everytime when it cools down. The problem has been slowly more consistent over last several months. (The PROBLEM must be due to heating/overheating or heat related malfunctioning of a starting mechanism, i.e. say Starter, solenoid etc)

What it does:
when key is turned,
-I can hear fuel pump coming on
-then there is a click
-but no cranking
-The display panel shows normal lights at the regular startup and shows no specific problem(s). When it does not start, there are minor differences (the engine temp light and another indicator to the right of that does not light up, please note that these two lights come on only temporarily at normal cold start). This prompted me to change the ECTS to see whether it makes any difference. The old ECTS was cracked but changing made no difference to the "not starting when hot" problem.

What it is not:
-The battery is replaced (after the problem started) and brand new and keeping its charge in full strength, judging from lights and cold starting
-I changed the ECTS (engine coolant temp sensor) with OEM part, does not help. The ECTS electrical connector leads appeared clean and brand new.
-The dealer could not trace the problem and say (annoyingly) that they cannot find problem with starter, alternator etc after thorough checkup.
-The car has only 59000 miles and in good shape, everything else and have never been abused

Additional info: The temperature gauge warms up to 1/4th and stays around that mark if the car is driven, i.e. it is air cooled. The marker goes beyond 1/2 mark, almost closing on to the 3/4th mark, when the car is idling, i.e. not being air cooled. Not sure exactly when the cooling fan should kick in in normal condition. The reason for mentioning this is, if say the starter is not working at high temperature, whether that high temperature is unusually high and that in turn is causing the malfunctioning.

Would love to get an expert opinion to troubleshoot this starting problem, which is really frustrating. I am sure there is someone who can diagnose this just by reading the symptoms. This finding is quite common among Saturn S series users but I find no solution after extensive google search. I appreciate all opinions from experts or other Saturn users (of their experience with a similar problem), but just a blanket statements 'change the starter', 'change alternator', 'change battery' etc will be of little help.

 

If that sucker has a torque converter lockup switch, it could be defective. I don't know if it has one or not. Or perhaps it's simply a bad starter that the armature swells in when it gets hot. If that happens, it won't spin the starter until it cools off. I'm just guessing, I'm not a mechanic.

 

I'm sorry, all I can do is guess, but if it was mine, I would be out having volt meter measurements taken at various locations and observations as to what is being turned on and turned off when the key is turned.
Now where? Based on information at the moment, don't know. But certain dash board lights are supposed to go on and off as the key is turned.
What happens to head lights when trying to start with the problem and if you had turned them on prior to trying to start.
There are a number of sequence indicators that help point at where to look next. But most importantly I would start with battery voltage conditions before, during and after trying to start.
It takes two people generally to do this unless you have long clip leads to extend the reach of the ones on your meter.

 

I would have to agree with the starter. Or it might be the battery cables or a loose ground

 

If you had this problem before and after the battery change, then I would rule out the battery, but if it is a new problem since replacing the battery, I would not rule it out. There are battery manufacturing defects that can cause these symptoms.

But for now, I will assume that this occurred before the new battery. Since you get a single click, that means the ignition switch and all the safety switches are working properly. If the battery had a bad connection or low on charge, you would get a series of clicks.

This pretty much isolates the problem to the starter. The click is the solenoid is working, that is the click you are hearing. When the solenoid activates, it does two things, it pulls a small gear at the end of the starter into the ring gear attached to the flywheel or torque converter. It also pushes a copper bar up to two large copper contacts to transfer current into the coils of the starter motor.

Either the copper bar and/or one or both of the contacts is burned to the point that it doesn't pass current or something is preventing the starter from turning. It appears that it is heat related so that kind of leads to the starter being prevented form turning. My theory is that one or both cap bearings is seizing when hot.

If you have a volt meter of some kind, put it on the battery terminals when the engine won't start and have someone try to start it. If the battery voltage remains fairly high, above say 10 volts, then that indicates the contacts are burned. If it drops well below 9 volts, then the starter is jammed. About nine volts is what you should see when the starter is turning under normal load.

More stuff: One more possibility that I forgot. It can be the brushes in the starter motor. They fit inside a sleeve and are supposed to be able to be pushed up to the armature by a spring. As the brushes get hot, they might expand and not get the spring tension they need to keep them pressed against the armature.

Now why would this happen now and not when new. I had seen this several times and did not understand it myself for awhile, until I noticed that all brushes seem to wear at an angle. That is the face of the brush that contacts the armature will wear more at the top or the bottom. This eventually causes the brush to **** a little in its little cage and get stuck, even though the brush still has plenty of wear left in it.

If you remove the brushes and straighten up the faces, they won't stick any more. Again, this would cause the voltage to be higher than normal, just like a contact in the solenoid not conduction, except this is a more plausible explanation for why it only fails when hot. Usually when the contacts go bad, they just go bad.

One way to figure this out would be to drive the car up on a lift when it wont start hot. The use a remote starter switch hooked up to the starter motor (not enough room to safely use a screwdriver to short the contacts) and see if the starter will spin when using the key wont. If the starter spins, that is the solenoid, if it just clicks, its the brushes.

 

Dear Keith,
Thank you so much for your detailed comments in trying to troubleshoot the problem. I will try to check all your highlighted points myself or get it tested next time I take it to the dealer. Naturally, if starter needs to be replaced (fixing is probably not possible for me), I would like to do it myself or get it done by the dealer.
One question on your comments: Based on the placement of the starter, is it possible/COMMON for the starter to get heated and malfunction (as you indicated) or the problem is deeper, i.e. there is somekind of engine overheating problem giving rise to this?
Once again, ny sincere regards and thanks for your time and help.

 

To Uncljohn: Thank you so much, I am looking into the starter malfunctioning more carefully now, as Keith has also pointed out. The puzzling thing is why the dealer would not find any problem with the starter after a throughcheck (according to them). May be they did not heat up the car long enough before testing. I will post more if/when I can troubleshoot. Many regards.

 

Not to take a cheap shot at a dealer, but:
The last dealer I took my Saturn to in order to have the moon roof window repaired at an estimated $350.00 previously estimated by the way as I had to save the money to have it done as I do most of my own work, started out with the nice man with the bow tie and the clip board trying to tell me that the car needed $3500.00 in repairs before it would be safe to drive it out such as $90.00 worth of windshield wipers and the the list went down hill from there. After we went through the list and asked why each and every one of these suggested repairs had an effect on the moon roof and then discarding them when it didn't I got to the $1700.00 replacement of he entire moon roof assembly vs the $350.00 motor repair which is why I came in, I ended up paying $750.00 for the repair instead. And had to take it back a second time to get it actually fixed under the repair warranty. And my Chrysler purchased new recently recieved a letter from the Chrysler dealer indicating it was over due for;
A list of flushes.
Of which in my opinion represent what is done to a toilet not a car and if I wanted to add some form of automotive fix it in a can I can do that myself for the cost of the can, not $50.00+ per flush that it is supposedly over due for.
By the way, that was the last time my Saturn actually saw a dealer and the first time in years I actually took it to a dealer. Although the dealer parts desk always went right by me. The nice man in the bow tie and the clip board was a bad joke. And the whole thing disappeared not to long afterwords.