baldguy010203

That title pretty much sums it up. It will start fine, and run for about 5 minutes, then just completely flat out DIE, not slow down and sputter and kick a little or anything, it's just like you turned the key off. It will crank fine after that but you will NOT get it started again, not even a sputter until you you wait a good hour or two, like some electronic part overheated maybe? Any ideas on trouble shooting? When that happens, I don't believe its fuel pump, because I can spray starting fluid in it, and it still does nothing. I swear I've checked for spark and it does seem to spark, but I haven't ever really seen how the spark SHOULD look, if its too weak, or not as often, I'm at a loss. I had a mechanic look, his first thought was, Air Flow Meter, he bought a used one, that was SUPPOSED to be good, and no difference. I'm hesitant on buying new parts if they aren't returnable if that didn't fix the problem. I don't off road with this at all, its just a daily "look good" driver, I have even thought about removing the EFI, and resorting back to the Carb days, just because there are less "unknown" problems.

I know a little about electronics, and I'm not afraid of a voltmeter, and testing resistance, but would need to know where to put each lead, (Pin 3 to pin 6 on a specific connector) and where that connector is. Or if anyone is in the San Antonio, Texas area, I'm in a smaller town about 30 minutes south of there and would love assistance!

13Swords

First thing I'd suspect is the ignition coil, as these symptoms sound pretty classic to that. When ignition coils get weak or start to fail, they will develop higher resistance with heat. That higher resistance "chokes off" the voltage to the distributor, so you'd either have no spark at all, or very weak spark that isn't strong enough to fire your spark plugs. Once you let it cool of for that hour or more, the resistance drops back down to a workable range, then it works again, until it reheats, builds higher resistance, then quits again. In my experience it's usually the Secondary side that fails first, because it handles much more voltage than the Primary side. Most Ignition Coils produce 30,000 volts or more.

You could remove the ignition coil & Igniter (Ignition Control Module) as a unit & take it to almost any major parts store & have them test the coil for free, & possibly even the Igniter. Or, If you have an Ohm Meter you can check the resistance on the ignition coil primary & secondary sides. For accurate readings you must remove the wire from the coil that goes to the center of the distributor cap, & disconnect the plug from the Igniter (ignition control module) that is mounted right next to the ignition coil.

Primary Resistance - Set Ohm Meter to low range (200 Ohms) & touch the meter's probes together to check for resistance in the probe wires. If it isn't zero, make a mental note of this number. If your Ohm Meter is self-zeroing you can skip that step.
Probe each terminal on the ignition coil where the plug from the Igniter connected. If you did have probe wire resistance, subtract that number from the reading you get. This will give you the accurate measurement for Primary resistance. My sources say for your year it should be between 0.2 to 0.8 Ohms.

Secondary Resistance - Set Ohm Meter to a higher range (at least 20,000 Ohms). Probe either terminal (usually the terminal that connects to the Black wire from Igniter, but either terminal should work), and at the Igniter plug connector, & probe the terminal for the wire that runs to the distributor.
My info says that spec should be 10,000 to 17,000 Ohms.

These numbers are taken with the parts "cold". If either measurement is out of spec, the coil is bad. If the Primary reads OK & the Secondary is within spec, but reads high (like 15,000 or more) then the Secondary is definitely the problem.
You can also try measuring the coil "hot". Start & run as usual until it dies out, then do the tests above. I'd suspect if you try this, the secondary will read beyond 17,000. If so your problem is the ignition coil.

If the Ignition coil tests out as good, it could be the Distributor Pickup Coil. That part can also fatigue with age & act just like a failing Ignition Coil; higher resistance when heated, which drops the voltage/signal it produces. That signal is only around 3 volts AC normally.
You can resistance test the Pickup Coil. There are two wires from it coming out of the Distributor (red & white or pink & white) with a connector plug. Disconnect the plug & probe both terminals at the same time. Spec should be 140 to 180 Ohms cold.

Let us know how you make out on this.

PS If it turns out to be the Ignition Coil, DO NOT CHEAP OUT ON THE PART. Those "economy" coils aren't even worth considering. If you want OEM Toyota you can get one here:
https://www.toyotapartsdeal.com/oem/...tra2=&filter=()
Toyota Part # 9091902197
Or you can get a coil from any major parts store for about $20 to $30 less. Just make sure it's a good quality brand like NGK, Standard Motor Parts or Delphi.

Pixilated pixel

I've come here because my 93 pickup won't start. What caused my trouble may be applicable here. The wire sheaths all over these old vehicles are prone to becoming brittle. Due to higher heat at the top of an engine In my case the wires on top of the engine are most affected. Most go to the vacuum switching valves. They shorted and caught on fire. I've replaced those wires. My trouble isn't over yet. I am looking for ways to check the coil, igniter, crankshaft position sensor and the ECU with an ohm volt meter. But anyway check the vacuum switching valve wires, the EGR wire and where the fuel line connects to the intake manifold.

JoeS

I had something similar. It was electrical issue in the distributor magnetic pick-up module mounted on the side of the distributor It would run for about 5 minutes then die. At 1st it started right up. In time it had to sit longer to start (cool down). Then it just quit and wouldn't start. Turns out it was a heat-up issue that cause an 'open' so no signal went through. When it finally died the shop figured it out.

Mine is a 1986 and the Toyota shop parts catalog said my year needed to replace the whole distributor. Didn't make sense as it slips on/off whnm the cap is removed. Call my normal Toyota shop. The old guy in parts said that's what it says, but her remembered the 89 module fit. Was $90 vs $650. Put in that 89 new module and it's been running fine for 18 years. Might not be your issue. Good luck.

2ToyGuy

A quick, easy, check of the coil and igniter, the distributor, and the plug wires is to hook your timing light inductive pickup to the coil wire, and then the plug wires. If it flashes, they're good. No flash, no good.
If you don't have a timing light, I strongly suggest getting one. It's a good idea to check and/or set the timing when you do a tune up. After you change the distributor cap and rotor. It may not have changed much, but if it changes even a couple degrees, it can reduce power and so on a fair amount.

Good luck!
Pat☺