20 Most Recent 1994 Toyota T100 - Page 6 Questions & Answers

It might not be the fan but the strain on the engine with the AC on the makes the engine heat up.
So a possible timing tuning of the engine is necessary to keep the engine in trim mode. Nomally the heat will also be related to the external temperature as it could make it worse.
An opinion from Toyota will be good to concur and decide.

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You really need to find out what your oil pressure is. I would connect a manual gauge to get readings...we don't want to take any chances when it comes to oil pressure. If your oil pressure is ok, then most likely the oil sending unit is faulty and will need to be replaced. I hope this helps.

Look at your large fuses for the starter, and battery/charging system, These should be on the fender power distribution fuse block.

An inspection is definitely in order.I would back it up on ramps or jack it and put it on jack stands. Have someone bounce it up and down while you look at it from below with a flash light if needed.

I hope this helps.