Buttercup, my '78 Corolla SR5 with 2TC engine, starts sometimes, and sometimes not. If she has rested in the carport for a few days, she cranks right over and goes like blazes. After a twenty-mile run, if I shut her off, she won’t start again. Not a sound not a click nothing. But if I leave her alone for a couple days, she cranks right over. I need to take the old girl through emissions pretty soon. I don’t want her to go into a coma in the emissions bay. Any suggestions? Her mechanics can find nothing wrong.
Glad to know you still have a 78 Corolla still on the road. Good on you! Looks like a nice classic you have there.
If you turn the key to “start” and don’t hear anything at all, no “rrr rrr rrr” and not even a “click”, that’s a no-crank condition on hot start. Could be something simple.
Could be the neutral safety switch in the transmission. It’s to prevent cranking if the transmission is engaged. If an automatic, will it start with the transmission in neutral? Have you tried wiggling the shift lever slightly left and right while attempting to start?
Could be problematic battery connections. Clean and tighten the connections at the battery .
Slight possibility of a defective battery, that goes south when it gets too hot. A battery load test when the problem is occurring would say “yes” or “no” to that idea.
Starter motors can fail when they get hot. That’s a pretty common problem. Cars often have heat shield to prevent this, but over the years of service, sometimes the heat shields are in the way and get discarded. Look for a missing heat shield.
Could be the starter motor is just kaput. Mechanics would test this by measuring the voltage at the two starter terminals (w/respect to the start case) during attempted cranking. If both are above 10.5 volts and the starter doesn’t crank, replace the starter.
Yep George covered pretty much what I was thinking as well. You need to do some tests after she has been running for the amount of time that you know the problem will repeat itself. AT THAT TIME…
DO THE FOLLOWING:
Measure your battery Voltage…see what you get. Do the Lights and Radio and other electrical items work? Is the Starter motor THE ONLY item that is totally dead after you heat up the engine? Check the other electrical items in the vehicle…if they are all working that IS GOOD… It means that the battery and its connections are NOT TO BLAME… If they don’t work either…then you can focus on the Batt, and all of its connections.
Lets say all the other electrics ARE WORKING… This narrows things down to the starter…the starter Solenoid…and or the starter wire CONNECTIONS.
It could be that when HOT…the starter solenoid goes on vacation. The test for this is to again verify ALL other electricals are working… Try to start the car… Not sure if this is a manual Tranny or AUTO… If AUTO…Do the checks that George told you…move the shifter from Park to Neutral etc…there should be a switch in the mechanism to prevent starter actuation while not in Park.
If its a manual…I DON’T BELIEVE that Toyota had a switch on the clutch back in 78’ but they certainly COULD HAVE one… Check to see that possibility
The last test is to simply Bridge the Starter Solenoid connections with a screwdriver or other suitable Wire or Metal to bridge the Solenoid connections and do the Solenoids Job FOR IT…SEE if the starter Comes to life and cranks the engine While you bridge the two connections on the solenoid…BE CAREFUL while doing this…make sure its not in gear bec you can start the engine pretty easily if you have the key in the RUN position. The Test will work without the keys in the ignition but it wont start UNLESS YOU HAVE THE KEY IN THE RUN POSITION
All you are trying to do is verify that you can make the starter motor turn on by bridging the connections.
You will have one of two results…Bridging the connects will run the starter motor…THIS TELLS YOU THAT WHEN HOT…YOUR STARTER SOLENOID ONLY…IS BAD and affected by HEAT.
It does NOT WORK…THIS tells you that you have a Power issue…Either the Batt has failed, is failing, or the power to the starter is interrupted somewhere by a broken or loose connection from starter to battery
If the starter does not turn on when you bridge the solenoid connections…YOU ALSO NEED TO VERIFY THE GROUND CONNECTION… This probably is NOT the issue bec the ground is usually GOOD if you can start her cold… and the Ground connect IS NOT AFFECTED BY HEAT.
Don’t throw out the good starter motor if only the SOLENOID IS BAD…MY GUESS IS THAT YOU HAVE A BAD STARTER SOLENOID…AND ITS REPLACEABLE… Just replace the bad solenoid if that’s what you have. LET US KNOW THE ANSWERS TO OUR TESTS AND WE CAN GO FROM THERE
Problem could also be the ignition switch itself. I once had one that failed when the temperature was below 10ºF. No sound, nothing.
I don’t think it is the starter itself, otherwise you would hear the starter solenoid click.
That leaves the ignition switch, starter solenoid, or wiring.
My guess would be starter solenoid that is failing when the engine gets hot.
Thanks, fellas. I appreciate your input.
Hold Some Ice On The Solenoid (Or Take Some Of My Snow, Please) When It Won’t Start. Then See If It’ll Crank And Fire-Up.
Some cars come from the factory with a shield that deflects heat from the starter/solenoid and over the years the shield either falls off or somebody, thinking it’s not necessary, removes and discards it. If that solenoid is near the exhaust manifold then perhaps it had a shield at one time.
So long as you don’t make contact with the starter wiring/terminals (short circuit fire works could result), you could construct a “tent” using aluminum foil to shield some engine heat from the solenoid and try that, temporarily.
Those cars usually had one little problem. The ground wire from the rocker arm cover to the firewall was connected to a well painted firewall. Remove the wire from the firewall and scrape the paint off the firewall, reconnect and the starting problem usually is fixed. I solved the problem on a 74 and a 79 Corolla by doing that. If there is some kind of clip that has been painted, scrape some of that paint off it too.
Offhand, sounds like a worn and/or heat soaked starter motor.
What the mechanics should do is run a current draw test on the starter motor. This is bone simple to do, only takes a few minutes and can reveal a dragging starter motor.
This is often caused by worn bushings in the starter which can allows the armature in the starter to make contact with the field windings.