With car hot, battery won't crank engine
 

Has anybody had this same problem?

When I have been driving my car and it is hot, after I make a brief stop to run into a store, my car will not crank over. It seems to be related to if the fans were running when I shut the car off. Then a few minutes later I get back in and its like the battery is dead and won't crank over the engine.

The battery is only about a year and a half old (84 month battery).

If I wait a few minutes and shut off the radio, and let the seat belts finish their cycle then it may then crank over.

I do not believe this problem is related to an electrical problem, just a weak battery because the car requires a higher load than the battery can delivery.

I checked the acid level in the battery and all cells are full.

Does anyone else have a similar problem?

Thanks, Ken

Have you checked the posts for proper contact?

Batttery posts checked fine
 

That was my first thought, so I checked and tighten the post and it still does it occasionally, were the car won't crank over.

Hey

I had this same problem...

until I changed the Fusible Link. (under the hood). It's a very cheap part (think under $3). Prior to that, I got it to start by taking out the fusible link, waiting a little, then putting it back on and/or taking the negative terminal off the car, then putting it back on. No clue why but it worked.

But yeah fusible link, its a cheap (potential) fix.

I had the same problem where it would sometimes just click and not do anything, but then if I waited a bit it would start okay (or if I just really went at it).

Turned out to be my ignition switch going bad, as per this thread:

http://www.subaru-svx.net/forum/showthread.php?t=27339

Ken, you need to be a little more specific in describing exactly what takes place.

(1) Is it that the starter motor does not appear to have enough power to crank the engine properly? Or ---

(2) Does the starter not operate at all, and if so is there a click noise at the starter, indicating that the solenoid is attempting to engage?

(3) Is there never a problem when the engine is cold ?

No Crank
 

Trevor,

Thanks for your reply and questions.

To me it seems that the car will not crank because there is not enough juice to crank the motor over. I do not think it is the starter solenoid because I have not heard just a click and nothing else. It simply will not crank over at all and dash lights dim when it won't crank over.

Also I have never had the problem when the engine is cold as of yet.

Thanks, Ken

Ken, this is all very strange.

One would think that the engine would crank over easier when hot and been running, and also so that the battery would have received a charge from when first started from cold. What is more it starts after only a short waiting time. Surely during this short time there could be no useful heat dissipation.

I think you must assume that you have an intermittent problem, not in fact related to engine temperature but more to the luck of circumstance.
The ignition start switch must be suspect on the basis of problems reported by others.

Can you verify that the starter actually engages and that there is a slight turning of the engine? If so this would rule out the switch and solenoid and indicates low voltage at the starter motor as could the dimming of lights. But why does it start after a short delay?

Taking all into account, try to diagnose the problem further. The battery can not be ruled out on the basis of the short length of use and must be a prime suspect.

Cheers, Trevor.

Just as a note--

With my problem (which was ignition switch), turning the key to the start position would dim the lights, and a "click" sound would come from the engine. It would do that until it finally started. There was no progression of it. That is...

If you turned the key, it wouldn't go from "nothing" to "click" to "turns over a little" to "almost starts" to "starts." It would either "click" or "start," nothing in between. Which is why I didn't suspect my charging system.

Same problems twice today
 

I had the same problem twice today.

It would not start if the coolant fans were running. I had to either wait till the fans cycled off, which took a few minutes or more or cycle the ignition switch a few times and hope that the fans did not come on again. If they did not, then the car would start.

From what I have learned heat is harder on a battery than cold and will cause a battery to decay quicker.

Thanks again for all the replies.

Ken

next time your car is not starting unplug the coolent temp sensor and try it again i have heard of this part causing starting problems.... but if this is a cranking issue have your battery tested and make that it is in working order, first. next you need to figure out if your starting issue it on the power side or the control of the starter circuit. you can do this by turning on the head lights and trying to turn the car over when its having this issue. if they dim then there is a high amp draw coming from the power side so you can assume the control side is functioning. if it doesnt dim its wire tracing time

He's already got this step down. ;)

While I'm not SVXperienced, as a general rule, hot starting issues are usually either battery or starter related.
As the underhood temps can easiy reach 140+ degrees this is a very harsh environment for electrics. That's why the ECU is generally inside the cabin.
Since you've replaced the battery I'll assume it's good.
Your local AutoZone will do a starter check on the car. If you have a clamp on amp meter you can do this yourself. Typical loaded amp draw is 150a. Over 250a indicates a bad starter.
What happens is the windings in a starter get broken. When the starter is cold they make contact, when it gets hot, the break opens causing the starter to draw more amps to make it turn.

Sorry to be a spoiled sport, but is best that members are advised correctly.

If the starter is drawing excessive current and simultaneously will not produce full torque, this will indicate shorted turns within the windings and heat can certainly increase this fault. The fault is a due to a breakdown in insulation between overlaying turns within the windings, which causes a short circuit and reduced effective resistance, rather than a broken/open circuit, as has been suggested.

Thank you for the correction. I'm MUCH more adept with AC motors, than DC. Being an electronics tech, dealing with AC more often than not, I get a bit lost at times.