my protege stalls out after 20-30 minutes of driving. if i am driving slow ,it just stalls out quietly. if i am going 30 to 50 mph, it will buck and hesitate and then stall out. if i let it cool down for 20 -30 mins. with the hood up, it will start right back up again, no problem. the symptoms started 2 months. if i tried to start the car with engine at normal operating temp. , I would have to crank engine for 3-5 seconds, one or two times. (when the engine is cold it starts in 1 second). i then drove va. to fla. for 1 month. it is 12 hr. trip. i did it non stop. when i got back 2nd symptom appeared. car would not start if engine at operating temp. if engine cold it would start right up. then car proceeded to current status after 2or 3 weeks, that is now it is stalling out after 30 mins. of driving. the car is not overheating, at least the temp gauge reads normal. i changed plugs and coils to no effect. the first time it stalled out i changed air filter. it was original air filter with some 80,000 miles on it . my bad .sorry folks. filter was black in middle with oily dirt on it. i need help. any suggestions?

 

change your pcv valve that might be causing the oily air filter, check your air intake air hose for cracks, is your check engine light on?

 

the check engine lite doesn't come on. I checked air hose but only from top. I will take it off car to do a thorough check. 2 mechanics independently told me they think it is a fuel pump. will change valve. thanks

 

Check cheapest solutions first.
1) Vacuum leak (perform a smoke check)
2) Coolant temperature sensor
3) Complete tune up if not done yet
4) Change oxygen sensors

 

When you open the hood for 20 to 30 minutes you still have a warm engine. Starting now is a hot start rather than a cold start. However the air that gets sucked is likely at a lower temperature than it would be without the cool off period.

You already changed plugs and wires. That's good.

It is very common that the Air intake hose develops cracks. These cracks can open and close when the engine rocks forward and back. Take the hose off and bend it while you look for cracks in the ribbed section. If there are cracks you can clean the hose and wrap it with duct tape.
Look for other vacuum leaks. Listen for hissing sound, spray carb cleaner at suspected places and listen for change in engine sound.

Clean your MAF sensor with MAF sensor cleaner. I like the CRC cleaner.

PCV valve (already mentioned by others).

Check the EGR openings at the mouth of the intake manifold. The '98 protege has two orifices: at the 12 o'clock and the 6 o'clock positions. Clean them if necessary. If the ports are clogged, take the the EGR valve off and clean it as well. Make sure the passages are free. B12 Chem tool can be very useful here. The thing is the EGR should only get active when the engine is warm. Mabe the valve does not close anymore. Cleaning can possibly fix that.
There should be an EGR boost sensor on the firewall, passenger side. Follow the vacuum hose down behind the intake manifold and pull it off the nipple. Poke into the nipple with a piece of wire. About 3" is enough. If you feel resistance push through. This place clogs up and hampers the vacuum signal to the EGR boost sensor. It really is a manifold absolute pressure sensor, nothing gets boosted.

Just for the heck of it: clean the battery posts and cable ends. Make sure to reconnect them really well.

If none of that helps you may have to do a fuel pressure test.

You say the check engine light is not on. Can you confirm the CEL coming on when you turn the key to "run" without starting the engine? The whole Christmas tree should light up.

Report back.

 

all lites come on in dash when I turn to on position including cel . took off air flow hose and looked for tears while bending it. didn't find any openings. there are a few small superficial cracks in hose but hose looks good. took off coolant temp sensor and did resisistance check in kitchen.checked out okay. replaced fuel pump. didn't solve problem. car hesitates after 30 min drive and is hard to start when hot. car has 84k miles and I am original owner. I drive car very easy. I change oil every 4-5k miles. I did let car sit from oct13 to apr 14 in va. due to trip. we had a lot of snow that winter. only disconnected neg of battery. car ran fine before that.problems started after returning from trip. I haven't changed spark plug wires yet. I only replaced one of two coils (in may). then I alternated two original coils to see if one of them was bad. didn't solve problem. so still have same problem. if somewhat hot it starts but runs real rough, bogging with no power. if engine very hot it wont start at all, just cranks over real strong. when cold starts up in 1 second but after 20-30mins of driving it will big time hesitate or stall out completely. thanks for tips will check out vacuum hoses. one time during big hesitation got a cel, it was code p1345 which is camshaft pos. sensor. but that occurred only once in past 2+ months

 

The fact that the car was standing over the winter does make a difference.

Standing this long the fuel in the tank will form precipitates that drop to the floor of the tank. These precipitates will block the pick-up of the fuel pump. There should be a sock to prevent the pieces from entering the fuel line.
Your car is likely stopping because of fuel starvation when the pick-up gets blocked. When you rest the car the bits float away and the car starts again. You can confirm this by measuring the fuel pressure at the start and again a few minutes later.

The mechanics who suspect the fuel pump are very close. Hopefully your fuel pump is fine and the pick-up and the tank will need only a clean up. If there is a fuel filter in the line it should be replaced as well. Many cars have an access panel under the seat to get to the fuel pump.

 

check the fuel pump pressure and check for a defective fuel pressure regulator. i would check the compression just to eliminate the possibility of a bad head gasket.

 

ever since i changed fuel pump and sock filter the car hasnt stalled out on me while driving. thats the good news. it has hesitated only once for 2 seconds while driving since pump change. now only problem is starting car when engine at full operating temperature. when i shut off engine it will restart in first minute or two, if i wait 5-10 minutes car wont start and there is no spark at spark plug. i only checked plug no. 1. if i open hood and wait 10 15 minutes it will start right up again. i checked sensors, pcv valve. only camshaft pos. sensor is giving me strange continuity readings. i will invetigate that now. i will also check my egr valve. thanks for help. p.s. the fuel sock was a little dirty ,light brown color in alot of places and dark brown in a few places. i didnt really examine it that well and threw it out after a few days. i wish i had .im pissed about that now. im 59 years old and it gets harder to think efficiently.

 

I think you are on the right track with that cam position sensor.

By the way, I am the same model year as you: 55