power cutting out/stalling. not the fuel pump

[Rambo]

This car is driving me insane. I changed the fuel filter and pump and realized I just wasted my money. I'm still having the same problems as before. The car just losses power and stalls randomly. At idle it usually dies and comes back alive a few times before dying completely. It also stalls out when driving no matter what the speed.

 

 

I checked the relay as well but I managed to make it click when I wired it up to my battery. When I turn the key I never hear the relay click or the pump priming. Is it possible that even though the relay passed a few electrical tests its still faulty?

 

Does anyone have suggestions as to what else could be the problem? I heard clogged fuel lines could be an issue.

[Dee2]

Definitely sounds like a fuel problem to me but it could also be electrical or perhaps a clogged cat.

This article should help you diagnose the problem.

 

http://www.salemboysauto.com/faqs/faq-51.htm

[scoobiedubie]

Sounds like the distributor.  What year is your ride?

[Rambo]

It's a 94. What makes you think it's the distributor? Would I have to replace is or are there other options?

[ANIM_Hooneru]

Hey Rambo,

I had a problem like this with my first Subie, and noone could diagnose it. A 80-something year old Italian bloke who used to own the local dealership was the fella who sorted it for me...ill get to that in a minute...But first...
 

Even though that relay tested ok, (i.e. it pulled in), it could be worn out and not allowing current through pins 30 and 87. My bet would be swap it with another one and see what happens there.

If you are confident with your wiring skills, You could even rewire the fuel pump if you believe there is a problem there.

 

If you are concerned about blocked fuel lines (which I haven't come across in one of these) disconnect the line under the bonnet, remove the fuel tank cap and blow the line back to the tank with compressed air.
 

If you have been running fuel with ETHANOL in it, even as low as 10%, I guess you could be facing a blockage as the Ethanol eats the Cadnium coatings off the inside of fuel tanks, and leaves it floating about in there as flakes. As I said, still havn't seen one of these cars with a blocked line yet.

 

It would be good if when it stalls out on you if you knew if you were getting IGNITION power out to the coil. When I was a first year apprentice I had the embarrassing problem of my Leone only starting 30% of the time. It wound out to be the Ignition switch was worn out, meaning when I had the key to START the two contacts were linked, ie I was getting power through the start circuit of the ignition switch to power up the Ignition Coil and the Fuel Pump, however when I released it from START, to RUN, due to the wear and play in the switch, I lost power to my coil and fuel pump and stalled.

 

Checking if you are losing your ignition power when it cuts out on you while driving would be difficult unless you installed an ignition pilot light or something. What I wound up doing was creating a bundle of bridge wires and basically hotwiring my car. If you do the same and your problem disappears, id be looking at tracking down an ignition switch.

 

I drove around in my car like that for months before I found one, however I still had this intermittent stall/no throttle independent of speed regardless of weather I was cruising or going up hills, doing 20kms/h or 110km/h, and the little Italian bloke diagnosed it as Welch Plugs...Basically I had a welch plug that was pretty well rusted through on the Passenger Side, and if you can believe it, occasionally leaking into my rocker cover and filling it with water, and allowing water into the cylinders. Don't ask me how it never hydraulic locked, or suffered in any other way. Ill be damned if I can explain it. When I popped the cover off, it was squeaky clean. When I ripped the head off, it did not have a spot of carbon on it anywhere. The driver side head however was filthy.

 

Hopefully that isn't the case with yours, however it is something to consider if you have a mystery water leak you can't track down as well.

 

Good luck!

/endnovel
 

[scoobiedubie]

It's a 94. What makes you think it's the distributor? Would I have to replace is or are there other options?

In reading further, it is probably not the distributor.  But pick up a spare the at the junk yard, at the first opportunity.

[robm]

This sounds very much like a flaky relay.  Sometimes they work, sometimes they don't.  They tend to be temperature sensitive, and won't work when they get hot.

 

Swap in one of the relays nearby on the same rack.  There are 4, 2 for headlights, 1 for fan and 1 for the fuel pump.  They are identical, so for testing, it is easy to swap them.

 

Grab the whole rack of relays from the wrecker so you have spares.

 

Plug together the green test connectors to test the fuel pump.  With the engine off, ignition on, the pump/relay will cycle on and off about every 2 seconds.

[Rambo]

Ok I can confirm it's not the relay. Changed it up and the problem was still there.

 

I also opened up the distributor and it looked like everything was good in there.

 

Don't think the cat is clogged either since its new.

 

I am thinking the problem is electrical. When I would turn my ignition on sometimes you can hear the fuel pump running. Most of the time it won't though.

 

Is there any electrical part that would cause the engine to cut out randomly? I find that the car doesn't stall (as much) when I am accelerating hard.

[DaveT]

There are numerous connections between the battery, power distribution, fuse block, ignition switch, etc. Any one of them could get intermittent. I've seen wires break inside the insulation also. But that's rare. I might wire in a test light to key systems, such that when it quits, you could tell if that system was getting power, or loosing it.