Engine Intermittently Either Starts Normally,Doesn't Turn Over,or(Despite Cranking Fine)Won't Start

If the battery is 7 years old then it’s always a suspect. The symptoms of an iffy battery can vary and if the click sounds is from the starter solenoid that makes the battery even more suspect.

Assuming the battery is fully charged testing it should only takes seconds.

“Well known chain…” is also a suspect.

The notes above give the results of the BATTERY test already done (GOOD/replace soon), and the AMPS gauge has been in mid-NORMAL every time except when we were trying over and over last week (at which time is was at low end of normal).

Ok, the “click” but no-crank condition is a very common complaint here. Suggest to focus on fixing that first. Fortunately it is usually fairly easy to diagnose and fix. The most likely culprits are, in roughly this order:

  1. Faulty neutral safety or clutch start switch.

  2. Battery is worn out and is not be able to supply enough cold crank power to turn the engine. Especially a problem in cold weather.

  3. Battery cable connections between the battery and the starter (either or both + and -) have too much electrical resistance somewhere in the circuit, so that even though the battery remains good, the power delivered to the starter motor isn’t enough to crank the engine. The starter motor requires about 100 amps to crank the engine, which implies all electrical connections in the primarily power circuit must be less than 0.005 ohms.

  4. The starter motor is faulty. Usually the specific cause is the starter solenoid contacts are worn out from all the starts over the years. Those are part of the starter motor, so the most common solution is to replace the starter motor.

  5. The ignition switch is faulty.

  6. Higher than normal resistance in the circuit from the ignition key to the “start” terminal on the starter motor. Could be due to a faulty neutral safety switch or clutch start switch or corroded or loose connections under the dash, or a faulty starter relay (this is a small relay that usually plugs in somewhere under the dash).


Rather than taking a wild guess and start replacing parts at random, an experienced mechanic would first measure the two voltages at the starter motor (battery power & start signal terminals) during attempted cranking. If the engine doesn’t crank and either terminal is below 10.5 volts, the mechanic would work backwards to discover why. If both measure 10.5 volts and above and the engine doesn’t crank, the mechanic would replace the starter motor.

If you want to try something yourself, besides verifying the battery connections are clean and tight, the easiest would be to see if you can get the engine to crank by manipulating the automatic transmission selector slightly while turning the key to “start”. Sometimes the neutral safety switch will make contact then. Or try starting with the selector in neutral. If you have a manual transmission, you could likewise try slightly changing the position of the clutch pedal (with the transmission in neutral). I doubt this will work in your case because you hear a “click”, but no harm trying.

My wild guess if I had to take one, based on your symptoms and the time of year, is your 7 year old battery is just not up to the task of cranking the engine when the ambient temperature is below a certain threshold. Or that your battery is marginal, but you have another of the above problems too.

Update: Today car did not crank from the get-go. Weather today was sunny and mild, at least high 50’s.
This time I did nothing other than pausing the key at the “on” position on the way to “start” position on second try, after the the initial lack of response. I kept trying without any other “interventions” in order to keep things uncomplicated and to find out whether the failure to start was beginning to be more reproducible for the mechanic, before resorting to depressing the inertia switch reset after 5 unsuccessful tries in a row. (The car then started up without a problem. Took it back to the shop. I now have several instances to go on, i.e. enough by conclude that it could well be more than coincidence that resetting the inertia switch was followed by the car then starting. Nonetheless, we have no idea why-- even if the inertia switch IS involved-- that on previous unsuccessful starts we didn’t get the cranking that we would expect to still occur, since the inertia switch should only influence the fuel supply. Also, the shop manager pointed out that if the switch were so prone to trip in the absence of excessive jarring, he would expect it to have tripped while driving, too.
(Was there 4 hours waiting for my ride, and it wasn’t yet pulled in to look at. Will post any news as I get it.)
Who knows what they will or will not figure out , so
kindly continue to post any input.

(Car is MANUAL transmission.)

GeorgeSanJose,
RE: "(faulty) neutral safety or clutch start switch…If you have a manual transmission, you could likewise try slightly changing the position of the clutch pedal (with the transmission in neutral). I doubt this will work in your case because you hear a “click”, but no harm trying."
Can you tell me about these components? I have not heard of them. I’m guessing maybe these guard against the car being inadvertently started while in gear?
What would be accomplished by altering the position of the clutch pedal? (Perhaps to get the clutch start switch to engage?)
Likewise, why would the audible click probably rule out trying this making any difference?

[Note: I think I understand the basics of the function of the clutch but cannot picture the assembly itself, so you may need to make that more concrete in order for me to follow your explanation of the parts I asked about.]

@FordProbe‌

It seems to me the first thing to do would be to replace that physically broken inertia switch

Who cares that it didn’t trip during normal driving

A good rule of thumb is to first replace visibly defective parts, before theorizing about other things

(The plastic to which I am referring is just the plastic reset button that merely rests on top of the inertia switch, which has cracked across halfway down the “stem” as a result of the recent handling. Although if it falls off it must first be replaced into the slot before using, it still operates fine. Perhaps the whole unit will need replacement due to other problems, but this broken piece is really just cosmetic; it still operates fine to engage the parts below to reset if necessary.) It’s just an indication of the car being 25 years old.

Without a clear understanding of whether there is a failure to crank or a failure to start the situation is beyond me.

OP writes …

Can you tell me about these [clutch safety switch] components? I have not heard of them. I’m guessing maybe these guard against the car being inadvertently started while in gear?
What would be accomplished by altering the position of the clutch pedal? (Perhaps to get the clutch start switch to engage?)
Likewise, why would the audible click probably rule out trying this making any difference?

Yes, a safety feature. The primary purpose of the clutch safety switch is to prevent cranking unless the clutch pedal is pressed down. It is so if you leave your kids in the car while you go into 7-11 and forget and leave your keys in the ignition, the kids won’t be able to turn the key and have the car drive though the wall and into the store. Because they won’t be pressing on the clutch, so nothing will happen, no crank, no start. On my Corolla one time this switch failed and I temporarily fixed the problem by bypassing the switch entirely. I don’t recommend this though as it defeats the safety purpose of it being there.

The clutch safety switch is usually attached to the clutch pedal in the passenger compartment, and over time can wear out and fail to conduct electricity. It is often two parts that slide with respect to one another and could get a bad spot, so it might work with the clutch pedal pressed almost all the way down, but not when pressed all the way down.

When you get an audible click from the engine compartment, that is usually the starter solenoid, which is only triggered if the start signal makes it from the ignition switch through the clutch start switch and to the starter motor. So the ignition switch and clutch start switch are most likely ok by your symptoms. But the only way to know for sure is the voltage test during attempted cranking described above.

Update: Car’s been at the garage since mid-day Friday, and they have started it “at least 50 times” without a problem, trying leaving it running or shutting it off. In the meantime, they have “dug deeper”, looking at fuel pressure and electrical spark voltages for a “weak spot”. So far, nothing detected.

When you have this problem, has the car been outside or inside? Is the shop doing the same thing?

The problem has been volleyed back and forth a great deal and while I remain somewhat confused let me inject that if the problem is most often experienced after a long period of relatively cold temperature you might check the viscosity of the oil. During the rare cold spells we get here there have been a few instances of cars that showed up with complaints of no start and they had no compression but after a few hours in the shop the compression would mysteriously increase. The problem was 10W-40 oil at near 0*F. The cold oil was too thick to bleed down in the hydraulic lifters, holding the valves out of their seats. But good luck.

Update: The shop manager has started it personally at least a couple dozen times and only notes observing a slower-than-usual cranking versus his older Honda Civic, which he describes as cranking twice before starting (rrr-rrr-rrr, rrr-rrr-rrr) but then starting up fine. Two or three techs have also started/listened, and they don’t reproduce a problem. Fuel pressure is good, spark plugs and voltages wherever they measured are good. I specifically asked whether the ignition switch and starter have been ruled out yet as potentially involved, and apparently they have. He said it could be that the engine is taking more time to build compression. Mentioned that something like cleaning the throttle body injectors could help, but that it may not, and since I’ve tried priming the fuel with no improvement, at this point he doesn’t feel that more action is needed. I told him to go ahead and put the new battery in before I pick it up tomorrow, even though it is doing fine with the older battery-- just so that wouldn’t be an additional complicating factor the next time I experience the car acting up.

@‌FordProbe

“He said it could be that the engine is taking more time to build compression.”

Did anybody measure compression?

Or are they just theorizing again?

For what it’s worth, my brother’s car had low compression, which led to extended cranking times.

Once I resolved the issue, it started up almost instantly

[The oil that I was told to purchase here in the south is 10W-30.]

 Over the past week the car was sometimes (probably much of the time) being started out in the parking lot, rather than inside the building, since the shop's bays were always full of other customers' cars being worked on.  Overall, temperatures have been much more moderate, though for most of the day (50's or 60's).  However, the shop manager did mention that it even started fine for him on a very cold morning, too, which was probably in the 20's or low 30's overnight.

 If this matters, the car was initially low on oil, that first time it didn't start on the cold night when we were trying to jump it.  [The reason it was low on oil is because the valve cover gasket is leaking (despite having been replaced once during the life of the car, at around 77,000 miles, I think-- maintenance log is out in the car), and I had forgotten for quite a while to check and add some oil to compensate for the gradual very slow loss.]  

Each of the other times that it wasn’t starting the following week (with crank/no-start or no-crank/no-start on different occasions) was -after- the oil had been topped off. The oil does still need to be changed, though.

 The garage evidently didn't measure the compression.  I would be interested to know how involved it is to do that. I suppose the reason they didn't was due to the time involved, since I wasn't being charged any additional diagnostic fees while they kept it this week and checked periodically to see if it acted up again, along with some further measurements mentioned above.  So how would compression be directly measured-- how are the cylinders accessed to do this?

@FordProbe‌

I hate to tell you . . . but it sounds like that shop isn’t terribly interested in properly diagnosing your car

In fact, it sounds like the extent of their diagnosis entails checking if the car will start

To check compression, you run the engine up to operating temperature, then shut it off. Then you remove the plugs, block the throttle open, disable fuel and ignition, put in the compression gauge instead of the plugs, crank over the engine and note the readings for each cylinder

I obviously simplified and may have left out a step or so, but you get the general idea

Have you replaced that broken inertia switch yet?

I don’t know folks, anyone else thinking the fuel pump is going south? Needs a new battery for sure anyway after 7 years and 300 amps, but the switch makes no sense unless either it or the pump is getting bad.

@Bing‌

OP said the inertial switch physically disintegrated in his hands

He even said he had to put it back together for it to start

I suggest at least fixing what you can see is broken first

I missed that one. Nice when stuff falls apart so you know for sure what to fix. No brainer, battery and switch first.