Hey, I have a 1997 Tacoma 2.4 The timing chain went at 440,000, so I replaced the engine.
Even though my truck is standard 2 wheel drive, my son found an automatic 4 wheel drive engine and we put it in.
It ran great for 300 miles then shut down while driving at 55 mph.
The engine will run once it cools down, but when it gets warm, it sputters and dies. (idles at 1k when cool, then when warm drops to 500, shoots back up to 1k, then back to 500 and then dies.) If I keep the rpms around 2k it runs fine until I let it down to 1k and then it just dies. It has new plugs, wires, a new coil, rotor, cap and starter. Someone told me it could be the distributor. Any ideas?