Why might a car's starter perform better when the engine's cold?

Factual Questions
1

FTR, I did run a search on this … found a potentially useful thread, but not one that directly addresses my question.

Long story short: my truck ('95 Nissan XE 4 cyl automatic) starts great when the engine’s cold, or relatively cold (i.e. parked for 10 minutes). But if I shut off the engine to run into a convenience store for a minute, then come back out and attempt to start the engine … nada. The alternator (?) seems to kick in fine … just sounds like “runh … runh … runh …” with the engine never kicking in.

Wait 10 minutes, all is well.

The last time this happened to me a few days ago, I got impatient and just held the key in place through several “runhs”. Although I’ve gotten away with doing this in the recent past, this last time the starter complained with a loud “WHIRRRR!”. I thought I fubarred the starter right and good this time, but I tried starting again a few minutes later anyway. More “WHIRRRR!”, and more immediately, too :frowning:

The truck gods were apparently smiling on me, however, as I was able to start the truck just fine after letting it rest a good 20 minutes (which I spent walking over to a conveniently-placed full-service Goodyear shop for some quick over-the-counter advice). I really thought I might have ground the teeth off the flywheel … but perhaps I got lucky. The mechanic suggested the solenoid and bendix, but was pretty gung-ho about selling me a new starter.

Anyhow, the truck has started fine since, though I’m twice as careful about giving the engine time to cool (for quick errands, the engine is left running now).

So … the GQ is: how is engine heat affecting the usual action of the starter?
Full disclosure: the truck is overdue by time (7 months) , but not by mileage (3200 miles), for an oil and oil filter change. I can’t recall the last time the fuel filter was changed (I know, I know :o ). The truck is also on its original serpentine belt (should I be :o ?). Lastly, the truck has just very recently been idling way too low … so low that it has stalled at red lights a few times. The workaround has been to put the truck in neutral and give a little gas while I’m stopped, to keep the RPMs around 1000.

2

It certainly sounds like the solenoid’s acting up - either there’s an intermittent electrical connection internally, or the thing is warping just enough for the bearings to bind up.

Solenoids and starters are so closely intertwined that it’s normal to swap the entire unit. By the time you take the starter out, disassemble it, replace the solenoid, put it all back together and back into the vehicle, the starter motor itself will be making plans to spite you and fail in nine days, forcing you to do the whole thing all over again.

Just in terms of time, I’d wager you’re rather overdue for a serpentine belt.

3

I would say the engine heat is causing something to expand , probably the starter moving it out of line with the flexplate or torgue convertor… I would expect this would be evident once you remove the starter from the vehicle. As the bushings/bearings normally keep the shaft of the starter in alignment in relation to the flexplate /convertor this is most likely what is worn . Failure to address this promptly will likely result in other components suffering damage. Most likely the flexplate or convertor , a far more expensive part as well as more labor intensive to remove.

I am not a mechanic so this is a wild ass guess.(for the most part)

4

You’d get similar behavior if your alternator was dying and you were running on the battery alone. Running the car would discharge the battery and it wouldn’t have the oomph to start the car. Leave it alone for a few minutes and it would (somewhat) regenerate itself.

If this is the problem, though, it’s only a matter of time before you’re dialing AAA.

5

You might want to PM **Rick **or Tuckerfan. Those guys know their stuff when it comes to cars.

6

Thanks, all, for the responses. Checking out the alternator and battery is an inexpensive first step. This truck is on its second batter, alternator, and starter. Maybe its time for thirds.

7

It’s the starter motor’s bendix gear and it will only get worse, so get it fixed ASAP. You can have your starter motor rebuilt which is much cheaper than buying a new one.

8

There may not be a simple answer to this problem.
It may be a syndrome,( In medicine, psychology and CARS, the term syndrome refers to the association of several clinically recognizable features, signs, symptoms (discovered by a machanic),

Good Luck

9

Thanks, Dog80. What’s happening with that bendix gear in response to the engine’s temperature?

10

Tell me if I’m reading this right. If you try to re-start right away, everything sounds normal, except that the engine doesn’t start running. It’s turning over at the right speed, making the right sounds, just no VROOOM! Wait 10 minutes, the same turning over sounds but the engine runs.

If this description is right, then there’s nothing wrong with your starter or alternator or battery. At least nothing wrong with the starter until the WHIRRRR! thing that just happened.

If it’s turning over at the right speed, the only thing preventing it from starting is either bad spark or bad fuel/air mixture.

11

Precisely.

I hope that’s the case … need to figure out a way to reconcile yours and Dog80’s advice. I know it’s impossible to diagnose this stuff 100% without an actual live inspection, of course.

Yeah … I “de-toothed” the flywheel on a Granada one time when starting it “agressively”. I feared that’s what happened, but apparently not (phew!).

… she’s not been tuned up since 1997 ( :o ). Same plugs and all. I’ll add a tune-up to the list.

12

I don’t know that I agree with the answers so far. As Cheesesteak pointed out, it sounds like the starter is working just fine. My guess would be that you’re not getting any fuel. I had this exact problem with a 1985 Honda CRX - It would start just fine in the morning, but if I had been driving for awhile and I shut off the engine, it would not re-start. Turned out to be the fuel pump relay, which was failing every time it got warm. Fuel pump relay didn’t work = no fuel = engine turned over but didn’t start.

13

Perhaps that explains the occasional killing at red lights, as well?

So … was that fuel pump relay a major expense?

14

No, not major. It’s a pretty simple repair. But I should have been more clear - I don’t know for a fact that’s what the problem is. There are other things that could prevent the engine from getting fuel. I think it is a possibility, though. If the relay were going out, it would progress to where it fails more and more, and eventually wouldn’t work at all.

15

Alternators don’t go runh, runh, starters do. So based on what else you have written, the starter is cranking the engine over, but it is not catching and starting, right?

Starters can overheat, and the bendix may partically disengage causing a loud grinding noise. That is a big clue to stop doing that.

Based on what you have posted here, it probably is not the starter.

Read on grasshopper.

Don’t sweat the oil change, it probably is not the cause of the problem. Or the fuel filter for that matter. The low idle is an issue that may be related.
OK listen up, for your engine to run you need the following:
[ul]
[li]Fuel[/li][li]Air[/li][li]Spark[/li][li]All of the above items in the correct amount[/li][li]All of the above items at the right place, and at the right time[/li][/ul]
If you have all five of these, your car runs tits. Too much or to little or in the wrong place the engine either won’t start, or will run poorly.
Based on what you have posted, I would guess the root cause is either
[ul]
[li]Fuel pump issue (relay as has been mentioned)[/li][li]Idle air control valve sticking during heat soak either allowing too much or not enough air into the engine[/li][li]Lack of spark due to a heat related open circuit[/li][/ul]
You need to test for the fuel pump coming on during hot soak crank when the car won’t start. Have someone listen to the filler neck and crank the engine. They should hear a whine of the fuel pump running. While it is possible to have a pump run, but not produce pressure, it is real unlikely. (FTR I have seen this exactly ONCE in all my years of working on cars)
Assuming the pump runs, then you need to test for spark. Again during the time the car will not start. If you know how to do this, fine. If not, I can tell you, but I must warn you that some ignition systems carry enough voltage to kill, and you may want to take a pass if you don’t feel confident that you can do the test safely.
If you do have both spark, and fuel that leaves either too much or too little air. You could also have injectors with a poor spray pattern, but I would bet on an air leak. Check all the plastic air trunks for holes, or splits or any thing that might allow outside air into the system.

16

Thanks for the detailed info, Rick. I won’t be able to do anything constructive to fix this, but now I will be able to speak to the mechanic more intelligently. Before your post, I’d have fallen for the “new starter” angle pretty hard … now I know of other, less expensive things to have checked first.

17

This is a borderline zombie thread, but I thought I’d come back in and give a follow-up in case someone else has similar issues and searches this thread.

Short version: for all the wacky symptoms, I was able to carry on with this barely-starting truck for three more months.

Then this past weekend, a new work buddy offered to help with it. The battery terminals has tons of caked-on corrosion. He bought and installed new terminals, then used baking soda & water to clean off all the corrosion. Somewhere along the way, the old battery completely discharged. After reconnection, the starter wouldn’t even turn over.

A new battery cured all. Now she starts like a brand-new vehicle … hot, cold, whatever, whenever. If it weren’t for the seemingly heat-correlated symptoms, I’d have gotten a new battery much sooner. I was worried about expensive fuel pump repairs and such.

I guess I got lucky with this one – for all the things it could have been, the fix cost less than $90 (buddy’s labor was free, thankfully).