1997 impreza outback sport random stalling issue

I see you replaced the fuel pump , spark plugs an wires , fuel fliter an checked ignition coil pack , Connections ,ASD relay . And everything checks OK ?????? How did you check these thing's ? Testing electrical circuits with a DVOM - digital volt ohm meter ? Fuel pressure testing the fuel pump before replacing ? Does the vehicle have spark ? How about hooking up a scan tool that can view engine sensor data .A bad coolant temp sensor could cause hard starting. Did you check the dark blue with yellow trace wire at the PCM connector 2 pin 67 . This is the PCM control side of the ASD relay . Do you know how a relay works ? how to test at the relay base ? where in plugs into.
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check your grounds. I find many easy fixes by cleaning all the grounds around the engine bay. I would also check the ground at the fuel pump connector that wiring is prone to corrosion and breakage

coil pack or something in ignition

Fuel relays then the fuel pump.

Yes it is very much possible.But there are many other possibilities too,including starter and spark plugs issue.

If your engine cranks normally but will not start because it has no spark, or it stalls and won't restart because it has no spark.

You can also do a test to confirm the problem .The procedure to do the test is as follows:---

If your engine has spark plug wires, disconnect one of the plug wires from a spark plug and place the end of the wire near a metal surface on the engine. Then insert a small Phillips screwdriver into the end of the wire (the plug boot), or a small bolt or nail to provide a conductive path. Then crank the engine and look for a spark to jump from the screwdriver, bolt or nail in the end of the plug wire to the engine. If you do not see a spark, there is an ignition problem.

OR-----------

If your engine has a coil-on-plug ignition system with no plug wires, In that case remove one of the coils from the spark plug and insert an old spark plug, a spark plug tester or a screwdriver into the end of the coil. Ground the spark plug or plug tester to the engine, then crank the engine and look for a spark. No spark indicates an ignition problem.If the engine has no spark, check for voltage at the coil positive terminal when the ignition key is on. If NO voltage, then problem is on the trigger side of the coil (pickup, crank sensor, ignition module or primary wiring circuit).

But If there is NO voltage at the coil itself, then in that case the problem is on the supply side (the ignition switch or ignition wiring circuit).-----------------

Jeep cranks but no start:----------------

A jeep that cranks over but doesn't start, in many cases will be due to a bad fuel pump, a broken timing belt, an inoperative cam sensor or crank sensor. Also these problems are related to faulty spark plug. Check the spark at spark plugs when you start the jeep. Do you notice any spark. Actually you should see. If in case there is no spark then it's a spark plug problem. Also the coil pack gives power to spark plug. So check the voltage at coil pack. It will show 12 volt. If there is no voltage noticed at coil pack then its faulty coil pack that has to be replaced. If all the possible options checked out ok then check the car starter. The starter gets power from battery to start the jeep. If the starter is faulty then it will not let the car to start. Also check and confirm that there is fuel in the jeep. If its very low fuel then in some cases this causes the problem. Also check and confirm that fuel pump is functioning properly and the fuel filter is not clogged. One of the easiest ways to check for a fuel pump related problem is to spray a little starting fluid into the air intake while trying to start the jeep. If the car starts momentarily, then there's a good chance the fuel pump is not working or the jeep is out of gas. You can also listen for the fuel pump's humming sound when the key is first turned on. Also if a inoperative fuel pump is suspected, a good technician will always check to verify there is power and ground being supplied to the pump, to eliminate the possibility of a bad relay or electrical issue. Fuel pressure can be checked with a pressure gauge and if there is pressure, pulse can be checked at the fuel injectors in several ways including the most common, with the use of noid lights. If the injectors don't have pulse the engine won't start. ---------- This troubleshooting tips will help you to solve the problem. Thanks. Helpmech.

check you ecu. same problem happen to me in an izuzu rodeo. I let my fuel get to low and it sucked dirt into the filter and messed with that and it set off a code for the ecu and messed it up but if i had just replaced the ecu first i wouldnt have had to change the injectors or anything.

the icm, coil, and crank sensor all read off the opti. Chances are you have a bad optispark (distributor). I just went thru the same issue and found it to be the problem.

check your fuel pressure as well, you may have anissue with your fuel pump and or relay

I would do that plus test the plugs, wires and coil pack.

It sounds to me like you replaced everything but the most likely cause of a stall while driving...The crank sensor.

Stalling does not sound like an alternator problem. You have concentrated on ignition issues, have you looked at fuel related issues, including fuel filter and injectors? Much, much less likely, but air filter would also come to mind.