1981 Toyota Corolla won't start/crank when hot, starts when cool

Anyone out there still driving and loving their older Toyota? My 1981 Toyota Corolla wagon is beloved but developed a problem wherein when it gets warmed up and it is turned off, it may not start again until it cools down. When I say start I mean no crank, the starter will not turn over. All other electrical functions continue to work. The required wait is usually about 20 minutes and it will start again. I replaced the ignition switch in my steering column about four times (why four is another story) and the problem persisted. Web research indicates the starter motor should be replaced, that because the starter is close to the exhaust manifold it can get quite hot and the phenomenon is called ‘heat soak’ where the electrical conductivity within the starter becomes overwhelmed by the heat, raising the resistance to the point where it will not conduct adequately. But I just replaced the starter motor and the problem is still the same! I am quite perplexed. I was so sure that would solve it. Any wisdom?

There was a call on the show just withing the past few weeks with this exact same problem and Ray said to put a bag of ice on the starter to cool it off. I think he was just kidding, later he said the solution was to replace the starter, as this is a common problem with Toyotas. Sounds like replacing the starter didn’t work for you. hmm … well, you could complain to Ray and Tom I guess … lol …

You may have got a bad replacement, not an uncommon thing, or a installation problem (more common), those are always a possibility. Auto parts stores will often test a questionable starter if you take it to them. I have an early 90’s Corolla and have had starter problems, never the “won’t crank when hot” though. But I’ve investigated what all needs to be working for it to crank.

  • Battery must be good, pass a load test, fully charged, and the connections clean.

  • Both terminals on the starter (main power from battery, and start terminal) must measure at least 9.6 volts during attempted cranking. If either is below 10.5 volts during attempted cranking, your best bet is to find out why first. Measure between the terminal and the starter case.

  • If a manual transmission, the clutch safety switch must be working and have low enough “on” resistance. Likewise with an automatic transmission, the neutral safety switch.

  • On manuals, sometimes there is a separate small starter relay under the dash area. That must be working correctly.

  • Ignition switch must have low enough “on” resistance.

That’s something to start with anyway. Best of luck.