I have a 1996 Ford Escort that was giving me problems resulting in a new fuel pump and fuel filter, that was improperly installed and got that fixed. It has continued with the problems and they are getting worse. I had the fuel pressure checked, came out fine, then had a full engine diagnostic test, all testing fine. The mechanic suspects a sensor. The car acts like it is going to stall, then just when I think it is going to quit, it kicks in and runs great. I got bad fuel a while back and it is doing the same behavior except does not quit. It happens very intermittently, now in every driving situation, except since I brought it in. The mechanic said if he checks the sensor when it’s not happening, it would be a waste of time and money. Is this true? A faulty sensor will not read as faulty? This town is full of bridges, and the highway has long stretches of nothing and a mountain pass. He is suggesting I drive it until it happens again, then take it in, but that’s what I did the first time. Do I really have to wait till it quits in one of these driving scenarios? Thanks for any help you can offer.
Intermittants are very hard to diagnose but a crankshaft sensor could do that. If the engine loses the signal from the crankshaft sensor it will shut down so if it is momentarily losing the signal, that could cause the problem.
There is a device that I don’t recall the name of now that is plugged in to your car and reads all of the computer devices. When the problem happens, you push the button and it records the last minute or so of operation so that the technician can see what was abnormal. The larger service providers or a dealer should have the equipment or better diagnostic equipment.