1993 Legacy gremlins

[bridorf]

Hello everyone! I have a 1993 Legacy L with about 145,000 miles on it. It has been a great car, but has had an intermittant problem for about 2 years that is really annoying. Every once in awhile, it seems it has only happened on the freeway while motor is under load a bit, the car will lose a few cyliders causing the car to lose power - something you can feel in the steering wheel as well. When I pull off the road the car stumbles a bit and then dies. It takes a few minutes but then the car is ready to go again, usually - a couple of times the car acted like it needed to clear itself out with a few revs and then it was fine. The problem then disappears for a few months. I was told by the shop that services the vehicle that it sounded like the mass air flow meter, but the problem couldn't be diagnosed since it wasn't occuring (which is true). The only clue was O2 sensor faults that were occuring frequently - so I replaced the MAF sensor unit and hoped for the best, but it happened again shortly thereafter. This is the chronic problem, but lately the car has developed a bit of a misfire barely noticeable at idle, and has become seemingly sluggish and running a bit rougher than normal. Also on the past few really hot days on first start up of the day the fast idle kicks in but then the car drops idle speed as if it will die only to pick back up and be fine - it is definately running rough at these times until warm up is complete. I have done a minor tune (fuel filter, air filter, plugs) and replaced the plug wires (with bosch ones that are not very good, poor fit at coil in my opinion) but the wires were replaced prior to the rougher running situation. I am pondering the possibilites and keep coming up with bad plug wires, bad compression, bad coil, bad crank sensor, a second bad maf sensor, or a bad 02 sensor even though there is no check engine light on ever. Compression will be easy enough to check, but I don't think this is it. Does anyone, who has made it through this post, have any ideas what this might be? I don't want to start replacing parts as this is costly, but the car is not running quite right and nothing will reveal itself by failing completely - any suggestions please.

[Setright]

Dang it! I hate this kind of problem!

 

I would offer this general advice: If it's a mechanical problem, like bad compression, it should show up all the time. Most mechical faults don't change their mind and go away for a bit.

 

Before you replace any sensors, check all the connectors. Spray them with a switch cleaner, let dry and reconnect. Before doing this, disconnect the battery, so your ECU will forget it's troubled past. (At least one hour)

 

Let us know if this helps :-)

[Legacy777]

I had a similar issue with my 90 where it would stall out on me. It did this intermittantly for about a year. Finally traced it down to the MAF sensor. When you replaced the MAF sensor, did you get a new one, or used one? Is your car MT or AT?

 

I'd start with all the connections on the sensors. Only sensors i could think of that might cause this would be the crank/cam sensors. Or possibly something electrical.

 

Something you might want to try. At night in a dark place, open the hood and use a spray bottle and spray a fine mist over the engine, coil pack, sensors, and see if you can get the engine to faulter. Make sure to take off the plastic engine cover while you spray.

[bridorf]

Thanks for responses. I will try the connector thing in case there is any dirt or corrosion. To answer your questions...The MAF was new and the car is AT. My gut tells me its the crank position sensor, but I am not sure why. Then again maybe its fuel delivery related.?

[93leg]

So sorry to hear of your problems. I also have a 93 Legacy with the similar problems. I wish I had some suggestions for you, but I don't. I'll tell you what I have replaced so far. I have replaced O2 sensor, ECM temperature sensor, knock sensor, plugs, wires, coil pack and still have the problem you discribe. I was thinking of the MAF sensor, but the cost is holding me back. I've checked compression, injector resistance, fuel pressure and cannot find a thing. Hopefully someone will figure this out soon. There are many posts dealing with poor runnability, it must be common.

[SageRu]

I have a 93 with the exact same problem. It happened ~ 10 times over the past year. Suddenly the car won't accelerate, you push the pedal to the floor, still no accelleration, let off pedal and the car immediately dies. Pull over, remove key, wait a minute or so and it's fine for another month. However, now it's happening constantly. I can't get a 1/2 mile prior to it stalling on me. Plus now it doesn't recover quickly, it tries to cut off every time you hit the clutch (rpm to near 0). This thread of messages never ended up with a solution. Did anyone resolve the problem? How? I replace the coil, plugs and wires. I'd hate to waste any more money on the wrong fix. Can the O2 sensor cause the car to cutoff? I was thinking of replacing the ignition relay or O2 sensor next.

[sea#3]

Ok here is a possible answer to all your problems

There is a main relay located just above in a hell and gone location just above the interior fuse box . Brown relay with a brown connector ( says JIDTCO on it and a part # ) If you pull the knee pad off you can just see it on the far left way at the back

What is happening is the contacts in the relay go bad and cause resistance in the circuit that cause a voltage drop to the computer , which can not compensate for the drop

What usually happen is what you descibe , loss of power, check engine light on (not always) , pull off to the side of the road ,shut engine off restart and runs fine for either a short time or for months before it happens again

The relay is cheep( approx 25$) compared to changing MAF

For the price and maybe some skinned knuckles ( and may be a lot of swearing) Give it a try

I have fixed 3 cars this way

 

SEA#3

[SevenSisters]

I'm wondering what condition your fuel system is in. Have you noticed if the tank is above or below 1/4 tank when you encounter the problem? Fuel pump or pressure regulator may be to blame, as well as, connectors.

 

At low fuel levels, the pump runs hot and may kick out for an instant or two. Cools off and is fine.

 

Probably will be hard to diagnose, but if the plugs, wires and coil have been changed, it at least worth being cognizant of.

 

[93leg]

Thanks for the relay idea Sea#3. Could you also supply the part number for that relay? It needs to fit a 93 Legacy LSI. I have looked for, and found the relay. Now all I need is a replacement.

[SageRu]

The relay is the ignition relay. The original (for 93 Legacy L AWD) is manufactured by JIDECO, part # 25229 AA001. Also has numbers RELAY 2M / MR5A414A1K12V / 20702M on it. Advance Auto carries this as GP Sorensen #41-5005 for only $15. HOWEVER, I just replaced mine today and no luck. Thus far, I have replaced the fuel filter, coil, plugs, wires, air filter, pcv valve, cleaned battery posts and connectors and now this ignition relay. Still no luck. Tank is about 3/4 full right now. I added some HEET, just in case moisture had accumulated. No luck there either. I'm thinking the O2 sensor is my next shot. Mine starts fine, runs good initially, gives you that warm fuzzy and then as you reach about 50 to 60 mph, it suddenly just lopes, pedal to the floor and she continues to drag, let off gas to pull over and she dies. Starts back up rough, idle drops very low, but works good enough to get back home as long as I keep the speed < 50 or so. I'll follow up when / if I fix it. Good luck.

[sea#3]

Sageru

Sorry to hear that didn't help , it has for me ,but it was probably a different cause

In stead of buing a new 02 sensor disconnect it when it acts up and see what the engine rpm does.

Also when it is acting up give the coolant temp sensor a "wiggle" and see if it changes the engine rpm

I know this doesn't sound to professional but with out a scan tool and looking at live data it sort of hit and miss

SEA#3

[frag]

I would get a Haynes manual and check all sensors, doing first the coolant temp sensor and the crank and cam sensors. I would follow with the knock sensor. A malfunction of these sensors could produce the symptoms you have. If nothing shows up why not do a fuel pressure check.

Just a tought.

[T.J.]

Wow, this thread is like a support group for people w/ poor running Legacys.

 

I started a new thread called "Hi+'92 Leggy trouble" because I didn't know about this one.

 

Some things I would note are:

 

1. Replaced O2 sensor and the first cat. No luck.

 

2. Shop said that fuel pressure was fine.

 

3. Mine can have this problem on a full tank.

 

4. I have yet to check any of the other sensors or relays.

 

5. Yesterday, I added a bottle of Cheveron Injector and Valve Cleaner (4.99@Joe's) before I filled the tank. I drove 169.65mi. w/ kayak and gear. Plenty of up hill. Made the whole trip w/o a hiccup. This is not to say that the problem is necessarily fixed, but she did run well for me. Just a thought.

 

 

I plan on dumping a bottle of that stuff in the tank frequently over the next few months as well as using Mavel Mystery Oil every time I change the Oil (per suggestion of Richierich, thanks man).

 

I will keep yous guys posted.

 

 

Later, T.J.

[SageRu]

I unplugged the O2 sensor and the car ran worse than before, so I assume it's okay. Per co-worker's suggestion, I removed the gas cap. He figured from my syptoms either gas cap or fuel pump. The car ran for the first time in a while without the same problem recurring. It started great, ran good up to 80 mph. No problem accelerating. I drove several miles with no problem. Stopped at store and when returned, it died three times in idle, but again ran great once I got up to speed. I've added fuel injector cleaner (cheap stuff) several times in the past, but this could be part of the problem. I'll try some good stuff. Not quite ready to trust it yet. I figure if not fixed, I'll check fuel pressure next, then back to sensors. I'll reply when fixed. Thanks for the input.

[PacMan]

I unplugged the O2 sensor and the car ran worse than before, so I assume it's okay. Per co-worker's suggestion, I removed the gas cap. He figured from my syptoms either gas cap or fuel pump. The car ran for the first time in a while without the same problem recurring. It started great, ran good up to 80 mph. No problem accelerating. I drove several miles with no problem. Stopped at store and when returned, it died three times in idle, but again ran great once I got up to speed. I've added fuel injector cleaner (cheap stuff) several times in the past, but this could be part of the problem. I'll try some good stuff. Not quite ready to trust it yet. I figure if not fixed, I'll check fuel pressure next, then back to sensors. I'll reply when fixed. Thanks for the input.

 

Did you ever resolve this problem?

I have a '92 Legacy (actually a Liberty - I'm in Australia) with 200,00Km on the clock - and it's been doing this for a many months now. I've replaced the O2 sensor, Fuel Pressure regulator, Ignition relay and I even tried swearing at it but no luck. One thing that I have worked out is that it mostly happens when starting to climb a steep hill and slowly pressing the throttle to the floor. Before the auto kicks back a gear you can feel the engine start to run really rough and the power drops to almost nothing. Pull over, switch off, say a prayer or two, restart and it's fine - maybe for weeks. I dearly love the car but this is driving me nuts. I find many reports of this problem on the web but no concrete solution (that I haven't tried). Someone MUST have worked out what the heck is causing this problem by now - please respond!

[T.J.]

PacMan, my legacy was doing the same thing pretty consistantly. I started putting Chevron injector and valve cleaner in the gas tank about every other fill up and using Marvel's Mystery Oil every oil change.

 

It has been over a year since the last time the problem occured. Try it out!

 

Good luck, T.J.

[Cougar]

I would guess the problem to be with the fuel pump rather than the MAF.

[sparkster58]

Umm the H2..also has a fit once in a while (93' Legacy wagon)...if i slow down to turn a corner it will kill....iam going to replace the plugs/wires/fuel filter and see what happens....any suggestion on my prob anybody????

 

spark

[PacMan]

Thanks for the Injector Cleaner tip TJ.

 

The thing that troubles me is that I can't see how Injector Cleaner will "fix" the problem. The reason for my concern is that after the engine runs rough, I switch it off and it restarts fine. Then the car will drive up the exact same hill without a problem. So if it were clogged/dirty injectors then just restarting the car would not fix the problem (for a while). I did find that the Ignition relay was faulty as described in this site I whacked the relay with the engine idling and, sure enough, the engine cut out. Wow, I thought, this is it. But I cleaned the relay contacts and put it back in the car and now you can whack the relay all you like the engine does not miss a beat. I was sure this fixed the problem until a few weeks later when my Wife reported that "it's up to it's old tricks". I checked the relay again and it's fine. So it's something else. Another thing I've noticed is that the problem has occurred three times at almost exactly the same place on the same hill on the way to my Wife's folks house. The last time it did this I went back down the bottom of the hill and drove up again - the second time I was giving it some serious gas - no problems. Then, to my Wife's annoyance, I went back down and drove up the hill again gentle-like and I was really expecting it to fail - but the darn thing worked fine. Grrrrrr! I've had it in the shop and the guy said he couldn't find anything wrong but cleaned the injectors anyways. The thing sure idles nicely now but the problem still occurs. I'm starting to wonder if there's a bug in the Engine Management computer program. I can't see that it could be a crank/cam sensor because it's failed at the same place on the same hill three times - hills don't change sensors (do they?).

[Cougar]

I tend to think the problems are due to either dirty relay contacts for the ignition or fuel pump, or the fuel pump itself is intermittent. Just because the pump has good pressure does not eliminate it as a problem. It can still be intermittent.

[richierich]

Go look at this thread. http://www.ultimatesubaru.org/forum/showthread.php?t=22907

 

Might help you a bit. The valve are sticking in the heads. There is a certain spot on the valve that has more carbon build up, and that is why at a certain speed/RPM it stick rather than at full throttle. But what do I know, just do this for a living. Never had one that couldn't be fixed without a few treatment of Motor Vac. But have also used Mystery Marvel and Injector cleaners.

 

Thanks for the Injector Cleaner tip TJ.

 

The thing that troubles me is that I can't see how Injector Cleaner will "fix" the problem. The reason for my concern is that after the engine runs rough, I switch it off and it restarts fine. Then the car will drive up the exact same hill without a problem. So if it were clogged/dirty injectors then just restarting the car would not fix the problem (for a while). I did find that the Ignition relay was faulty as described in this site I whacked the relay with the engine idling and, sure enough, the engine cut out. Wow, I thought, this is it. But I cleaned the relay contacts and put it back in the car and now you can whack the relay all you like the engine does not miss a beat. I was sure this fixed the problem until a few weeks later when my Wife reported that "it's up to it's old tricks". I checked the relay again and it's fine. So it's something else. Another thing I've noticed is that the problem has occurred three times at almost exactly the same place on the same hill on the way to my Wife's folks house. The last time it did this I went back down the bottom of the hill and drove up again - the second time I was giving it some serious gas - no problems. Then, to my Wife's annoyance, I went back down and drove up the hill again gentle-like and I was really expecting it to fail - but the darn thing worked fine. Grrrrrr! I've had it in the shop and the guy said he couldn't find anything wrong but cleaned the injectors anyways. The thing sure idles nicely now but the problem still occurs. I'm starting to wonder if there's a bug in the Engine Management computer program. I can't see that it could be a crank/cam sensor because it's failed at the same place on the same hill three times - hills don't change sensors (do they?).

[Gnuman]

But what do I know, (I) just do this for a living.

 

Richierich, you owe me a new keyboard. . .

 

I wanna steal that quote.

[PacMan]

Love your call RichieRich!

 

Hey, what have I got to lose here?

I'm darned if I can figure out why it doesn't wanna go up certain hills. I'll give your idea a shot - but can you clarify what is "Motor Vac"? I live in Australia so if you can tell me who make this stuff and what it's called on the label I'm sure I can find it.

I've been thinking about this a bit more and it occurs to me that it can't be a bug in the Engine Management Computer program otherwise all these Lagacy/Liberty models would have had the problem right from day one and Subaru would have gone bankrupt by now. Therefore it's probably something to do with the fact that these 2.2 litre (pardon my "Queen's English" spelling) engines are getting pretty old now and the concept of the valve gear mis-behaving makes sense. I'm also starting to wonder if the problem is not caused just by the fact that I'm driving the car up a (fairly) steep hill. But the problem may be started by first letting the car roll down a long steep hill with no throttle first (high engine manifold vacuum for a couple of minutes). This may be sucking oil down worn valve guides and causing the valves to stick? Maybe it's something to do with the hydraulic lifters? Anyways, I'll give Moto-Vac a shot and see what happens.

[doug jones]

You should also check the connections and that there are no cracks in the tube feed the air from the MAF to the throttle body. I have seen this before and it will cause problems similar to what you have described.

 

D

 

Hello everyone! I have a 1993 Legacy L with about 145,000 miles on it. It has been a great car, but has had an intermittant problem for about 2 years that is really annoying. Every once in awhile, it seems it has only happened on the freeway while motor is under load a bit, the car will lose a few cyliders causing the car to lose power - something you can feel in the steering wheel as well. When I pull off the road the car stumbles a bit and then dies. It takes a few minutes but then the car is ready to go again, usually - a couple of times the car acted like it needed to clear itself out with a few revs and then it was fine. The problem then disappears for a few months. I was told by the shop that services the vehicle that it sounded like the mass air flow meter, but the problem couldn't be diagnosed since it wasn't occuring (which is true). The only clue was O2 sensor faults that were occuring frequently - so I replaced the MAF sensor unit and hoped for the best, but it happened again shortly thereafter. This is the chronic problem, but lately the car has developed a bit of a misfire barely noticeable at idle, and has become seemingly sluggish and running a bit rougher than normal. Also on the past few really hot days on first start up of the day the fast idle kicks in but then the car drops idle speed as if it will die only to pick back up and be fine - it is definately running rough at these times until warm up is complete. I have done a minor tune (fuel filter, air filter, plugs) and replaced the plug wires (with bosch ones that are not very good, poor fit at coil in my opinion) but the wires were replaced prior to the rougher running situation. I am pondering the possibilites and keep coming up with bad plug wires, bad compression, bad coil, bad crank sensor, a second bad maf sensor, or a bad 02 sensor even though there is no check engine light on ever. Compression will be easy enough to check, but I don't think this is it. Does anyone, who has made it through this post, have any ideas what this might be? I don't want to start replacing parts as this is costly, but the car is not running quite right and nothing will reveal itself by failing completely - any suggestions please.

[PacMan]

FIXED FIXED FIXED FIXED FIXED FIXED !!!!!!!

Oh, by the way, I fixed the problem!!!!

I spent nearly $500 on parts chasing this problem and a couple of hundred hours with my head under the bonnet and the dashboard (yeah, we like the car a lot - when it's running well). After replacing EVERYTHING (MAF sensor, coil pack, Fuel pump, pressure regulator, knock sensor, ECU, putting heaps of valve cleaner through it and a heap of other stuff) I'd run out of ideas and was looking to buy another car. I then decided to build a data logger to monitor the ECU inputs while I was driving the car. This is basically a device that monitored the inputs from the MAF sensor, the oxygen sensor, throttle sensor and also the outputs to the fuel injectors. I also hooked up a fuel pressure guage. It's amazing to watch all the sensors and the ECU at work as the ECU constantly adjusts the fuel mixture for optimal engine performance and efficiency. I found it hard to drive whilst also watching all the lights and displays but, in the end, it paid off. What I found was really bizarre. And I can tell you guys right now "stop swapping parts" because you will NOT fix the problem. Firstly, the problem is a design problem (yes, even Subaru get it wrong sometimes) which is causing the ECU computer to "crash". This is why switching it off and restarting makes the problem "go away". Secondly there is a wiring error in these cars - my wiring diagram does not match the wiring that is actually in the car. If my wiring diagram is wrong then Subaru have two design problems. The problem will show up with different symptoms too. Usually no engine faults are recorded (probably because the ECU has crashed) but if a fault is recorded - Oxygen sensor faults are the usual ones but also knock sensor faults will show as well. Other symptoms are lack of power, misfiring and engine pinging. I'll give you a clue - the engine is running very lean but the ECU computer cannot compensate for this and it cannot work out why. It does seem strange that the problem only seems to appear as these cars get older - the Jideco ignition relay contacts deteriorating definitely play a part in this but the relay is only exacerbating the other underlying problems.

I have DEFINITELY fixed my car and I can actually reproduce the problem at will. However, fixing the problem is not easy unless you're an electronic engineer (lucky for me, I am an electronics engineer, heh, heh, heh).

I'm trying to work out whether I can make a kit of parts to fix the problem which can be easily installed by a handyperson. My current fix is fairly complex and would confuse the heck out of non-nerdy electronic type people. How many people are still interested in getting a fix for this problem?