HELP '89 Toyota Pick-up Won't Turn Over when Hot

[JFD]

I have an '89 Toyota pick-up that has had the same problem every summer for going on 3 years now. It has been in the shop 4 times for this problem and they cannot find the cause. The starter has been replaced 3 times since the problem started. It is definatly a temperature related problem since it only happens in the summer when it's extremely hot out usually after the engine has been running a while but sometimes, if it's hot enough outside, it does it when the engine is "cold". I have zero problems all winter long.

When I try to start the engine, nothing happens. It won't even turn over. I THINK I may hear an extremely faint cliking sound (too faint to be the starter). A friend was telling me about a Toyota he had years ago that did the same thing and it turned out to be "the ignition chip" in the computer. I don't know too much about cars so knowing the correct names and terms for most parts is beyond me.

I don't know what else to do. Any help/suggestions are appreciated.

Thank you in advance.

[MMLM]

JFD
Did you ever find an answer to your problem with your 89? I have the identical problem with mine. I have taken it in and no one can seem to find what the issue is.
Let me know if you found an answer.
Thanks,
Marc

[Tafnar]

Check your fuel pump.

[JFD]

I havent figured it out yet but in talking with others I've narrowed it down to three possibilities.

1) Bad wire connection somewhere thats oxidized. When the temperatur raises high enough, expansion occurs causing a poor enough connection to not power the starter.

2) Oil leak "gunking" up the starter. The only thing with this possibility is I would think it would happen all year round and not just the summer time.

3) Cracked computer chip. When the temperature raises high enough, the chip expands and the problem occurs.


The bad ground is the first one I'm going to check since it seems thats the most common cause. The next one I'm going to check is the computer chip. Finally, if those 2 don't solve the problem I'll give the oil leak a try since I know I have a small leak but it's the most expensive fix (valve cover gasket I believe).

I don't think the fuel pump has anything to do with it since I can hear it turn on when I try to start the engine. And if I try long enough, I actually end up flooding it a little.

[MMLM]

This is what someone else wrote to my response. May be some other avenues to explore.

assemble the following:
1 one broken truck that is doing what you describe above
2 A 12 volt test light (available from Autozon for $10 or less)
3 Another person to help

do this test
1 make sure your test light works by connecting it across the battery terminals
2 crawl under the truck and connect the clip to a good ground and test the fat wire connected to the starter. the light should come on
3 test the skinny wire to the starter. You may have to take it off the starter for this, that is ok. The light should be off until your freind turns the key to start when you tell him/her to. (careful it may start this time!) The light should come on when the key is turned to the start position.

You should be able to do this test in about 5min or less. If the test light does not come on when it is supposed to then do the following.
1 Check the test light, is it grounded good? is the bulb burned out?(you get the idea be careful of operator error)

2 if the light does not come on the fat wire then you need to check that wire from the starter all the way up to the positive batt cable, there is a bad connection, fuse/link, or corrosion somewhere.

3 If the light comes on at the skinny wire but the starter does not work then you have a bad starter. They are expensive, try this repair first http://www.4x4wire.com/toyota/maintenance/starter/
If the light on the skinny wire does not come on then you may have a bad ignition switch/fuse/wire/clutch saftey switch/connector. I reccomend that you find a wireing diagram and start tracing.