1997 Jeep Cherokee Engine stalls

Hi nema38. Welcome to the forum. The crankshaft position sensor is the most logical and common cause of the problem you're describing but the air gap is critical. They come with a paper spacer or a plastic rib on the end. The new sensor must be pushed in all the way before it is tightened. If it is not adjusted properly, it can cause intermittent stalling. When a sensor is removed, then reinstalled later, the remaining part of that rib must be cut off and a paper spacer must be stuck on to set the gap. If it is not used, it is possible for the sensor to hit the flywheel or flexplate and be broken.

You're trying to fix this the most expensive and least effective way. That's by asking one mechanic to guess at a solution, then buying the expensive parts and installing them yourself. Also, bouncing from one mechanic to the next is not productive. That's like switching from one doctor to another one if he doesn't come up with the correct diagnosis on the first visit. They will keep performing tests until they DO find the cause of the problem, but you have to give them the chance to do more tests. If you let the mechanic keep the van until it is fixed, it will be done. I doubt you needed the fuel pump or the Engine Computer. If the mechanic would have put those parts in and they didn't solve the problem, he would have taken them back out and continued looking for the cause. By constantly going to different mechanics, they all are going to start over with the same diagnostic steps and you'll be paying for their service over and over. When they make a diagnosis and it turns out to be wrong, you wasted a lot of money on the wrong part. When they make a wrong diagnosis and THEY put the part in, that is just the first step. They continue to perform tests that lead them to the problem. In your case, they aren't continuing with the testing. They stop at the most likely cause because you take the vehicle to replace the parts yourself.

Does that make sense? I know I didn't do a good job of explaining it, but you're better off sticking with just one mechanic. No one always comes up with the correct solution with the first thing they test or try. They might have to test a dozen things before they find the problem, but you're not giving them the chance to go beyond the first thing.

Caradiodoc

Not all mechanics are familiar with every part on every car but for sure he will learn after breaking one of these sensors.

The correct air gap is the thickness of that paper spacer. There is no way to measure it because it is hidden. The spacer will slide off as soon as the engine is started.

While working at the dealership, I replaced 13 transmissions over a two-year period. On the last one, I didn't use that spacer when reinstalling the sensor. I just pushed the sensor all the way in, then pulled it out a little. I heard later that the engine ran fine for two weeks, then began stalling intermittently. The next mechanic diagnosed an intermittent sensor. The engine ran fine after he replaced it. Had he known the history about how I didn't follow procedure, he could have fixed it by just reinstalling the sensor properly with the spacer.

Caradiodoc

Well, I think we can rule out heat-related issues. That's one way sensors and computers fail. That kind of leaves the wiring as the likely suspect. While the engine is running, wiggle harnesses around and pay particular attention to electrical connectors. Fuel pumps rarely quit once they're running but don't overlook the wire going to the tank. A clue the stalling is due to an electrical issue is the engine will suddenly stop just as though you turned the ignition switch off. If loss of fuel pressure is the problem, the engine will slow down and sputter over a period of a few seconds.

Caradiodoc