My wife’s Accord generally starts and restarts perfectly fine in nice cool weather. However, when the temp rises above 70°f she has trouble RESTARTING the car.
She can start it fine in the morning, but if she turns off the engine it may be hours before it restarts.
I’ve rescued my wife on several occasions when she’s dropped the kids off at school, by giving her a jump start. Thought maybe the battery wasn’t charging enough, so I checked the battery and alternator with my brother in laws trickle charger. Both tested fine.
I’m leaning towards starter, but $90 is a hefty price tag to pay just to diagnose my suspicions.
What’s the likelihood that the heat causes the starter to poop out for a while?
Whan you say it won’t start, you mean it doesn’t crank, right? When you turn the key to “start”, there’s no 'rrr-rrr-rrr- sound, just no sound at all, or maybe a click, but the engine doesn’t turn?
hmmm … well, that’s a new for me. My Corolla, same vintage, it has exhibited this problem when cold sometimes, but never when the engine is warmed up. In my case the cause was starter solenoid contacts on the fritz.
What I’d do is measure the voltage at both terminals on the starter, between the terminal and the starter case, during an attempted start. If both are above 10.5 volts, and it won’t crank, that is probably a problem with the starter. You’d need to install a new one or fix the existing one.
If either are below 10.5 volts, let us know the situation and maybe we can help figure it out. That would mean there’s an electrical problem somewhere. If the car has a manual transmission, one likely cause would be the clutch safety switch. If an automatic, the transmission’s neutral safety switch. Have you tried jiggling those during attempted starts to see if it causes the engine to crank?
It turns over but just won’t start. The sound is different too. Not a whiney “trying to start” kind of a noise, just different.
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How do you check a battery and alternator with a trickle charger? Many auto parts stores will check a battery / alternator for free - with equipment made to test them.
In any case, though - if the thing turns over then it’s not the battery or the starter. That’s the starter’s only job is to turn the thing over until it fires up. All it needs to do that is the right size jolt from the battery. So if she turns the key and it turns over, then… I’m also wondering about the jump start connection. All a jump start does is send enough power to get the ailing car to turn over. So…I think maybe the “sound is different” might need some elaboration.
If the car is revving over when the key is turned, but the car won’t start and run then you probably have either a fuel or spark problem. You can get a cheap spark tester at any auto parts store to check for spark.
On fuel, you have one of two problems. One is too much fuel - something like leaky fuel injectors flooding the engine. The standard flood clearing procedure is to just hold the accelerator to the floor and then ease up slowly if it fires. The second is too little fuel. When you get a spark tester get a can of starting fluid. When it won’t start, blow some fluid into the intake someplace and see what you get.
For a while in the late 80s - early 90s Accords has known issues with their main relays. That is also worth thinking about.
I think you have a bad main fuel relay as @cigroller has mentioned. It’s a common ailment with cars of this vintage. The good thing is that the relay is easily changed and are inexpensive. The clue was heat. In cooler weather the main fuel relay usually works as advertised but when the relay gets heated it becomes erratic and intermittent. The fuel pressure disappears and the engine will not start. Change out the main fuel relay…you’ll be glad you did.
@Cigroller, the trickle charger I used had a few different functions. Whether or not it’s all that reliable? I don’t know.
My biased opinion is that the noise I hear, when I crank that thing over, sounds oddly like, “haha, gotcha, sucka”. 
it’s been a couple of weeks since I heard it, so I can’t remember exactly how it’s different.
At any rate, I will focus on the relay. That sounds well within my technical range, tbh.
Perhaps the trickle charger just has a function that lets you measure voltage? Then you could tell if the battery had good voltage and with the car running could tell if the the alternator was putting out appropriate voltage. That’s a good DIY quick test if that’s what it amounts.
Yes - the relay is basically plug n play. If you’re handy with a soldering iron, you can find plenty of info online about fixing the most common issue. It’s apparently easy enough the for many it makes sense over what I think is $20-30 on a new one. You can sort that out according to your own preferences, but if you search there is no shortage of web info on the main relay problem.
You might have someone hold a dollar bill next to the exhaust pipe and see if the dollar bill ever moves toward the pipe during an attempted start. If so, that’s an indication of a possible misfire, indicating a problem w/the ignition system. The confusing thing is why jump starting would help an ignition system problem. I’m assuming you don’t want to do the voltage measurement above, it is a sort of awkward measurement to do. So I think the first thing I’d do – before assuming the relay above is the problem – is a proper load test on the battery combined with cleaning the battery connections. It’s easy to do and it’s quite possible one of those is the problem.
The first thing you need do is clean the battery connections using a battery post cleaning brush. It is very common to have dirty connections and that causes low voltage at the starter. This is usually distinguished by a fast clicking noise by the starter solenoid.
I actually replaced the clamps when I was trying to diagnose the battery and alternator. I’ll let you guys know if the fuel relay its the culprit. Thank you all for your input!
Best of luck.