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Hello everyone, I have a 1990 Legacy L Wagon, 2WD AT with 2.2L. It has recently passed 220k miles and runs great. Six months ago, the ECU failed, and so because of my confused mechanic I have a new (well junkyard) ECU, cam and crank sensors, ignition unit, and timing belt (which was long overdue anyway). So, the last 6k or so I have had a very occasional problem where the tachometer will drop to zero while the engine stays fine. Ten to twenty seconds later, it returns. I have only ever noticed it when driving fast on the freeway. None of the other guages drop, and no lights come on - except yesterday. For the first time, the loss of tachometer was accompanied by a check engine light. So, it's starting to concern me somewhat more. Now, I know the tachometer thing is likely to be a bad connection in the instrument panel. But I was searching here and I found this thread: http://www.ultimatesubaru.org/forum/showthread.php?t=6059&page=1&pp=10 For the last 50k miles, I have had a more frequent problem somewhat like this - the engine will idle rough, up to about 1800 RPM, then smooth right out. Every week it will happen a couple times, but I just push through it and a minute later it goes away. Now it makes sense to me that THIS problem could quite likely be caused by the idle air sensor. So, I guess a just want a little direction for my troubleshooting. I'm assuming that the tach problem isn't a problem with the crank / cam sensors because the engine runs fine - even if I floor it while the tach is off, the engine responds perfectly. Could anything else, say the IAS, be causing the tach problem? Are my two problems related? And if I need to dive in to the instrument cluster, is there a good guide for that anywhere? Thanks for your help everyone... JT

Okay, this is a bit weird. My cas is a 90 Subaru Legacy, AT, 2WD, 210k with recent timing belt and computer. The other day I noticed that the dash lights were all a little dim - I attempted to adjust the dimmer but it was up. I also noticed that both the "Manual" and "Power" lights were dim as well - to my recolection these don't dim with the rest of the dash. A few minutes later it was back to normal - around the same time, but not ecactly the same time, I turned off the heat, but that is probably a coincidence. I noticed more intermitent dimming yesterday morning. So last night we went out to karaoke. Five hours later we are about to leave, and find that the battery has died. The doors seemed to be shut, the lights were all off, so I suspected a short of some sort since this battery is less than a year old and hasn't been run out yet. In the morning we jumped it and I drove home. I hooked up my trusty multimeter and found that with everything off, the system was drawing about .15 amp. Seems to me, that this isn't enough to kill the battery in a few hours, but just to see, I started pulling fuses to see where it was coming from. Now, when I was working in the fuse box, I left the door open, leaving the overhead and fuse box lights on. Radio was pulling a tiny amount - but when I pulled the "Illum" fuse, the whole thing went away. But, I guess there's something wrong with my methods, because when I pulled the fuse it blew a fuse in my multimeter. I switched to the 20A range (different fuse). Here's the weird part - when I re-connected the battery cable directly, the lights came back on, but when I pulled the fuse again, THEY STAYED ON. As though I hadn't pulled the fuse at all. So, do I have a bad fuse panel? Maybe that's where my short is? Have I overlooked something? Thanks for the input. JT

Thanks for the quick replies! This morning the mechanic called to say he'd been on the phone with Subaru tech support and they said that if the timing belt jumps a tooth and the cam and crank sensors are not in agreement, that might cause the ECU to read "no reference". Now, I know if I plan to keep driving this car, I need to do that anyway, and he's willing to do it cheaper - and faster! - than anyone I've talked to about it before. So, I told him to go ahead and do it anyway. But does what he got from Subaru sound reasonable? I'm surprised they didn't put in a code for an angle disagreement. Thanks for the input. JT

Hello Subaru experts! I'm in a tight spot and would appreciate any speedy advice - I will be trying to complete the repair tomorrow morning. I will be verbose as usual. The short version should be plenty, however. Short version: My '90 Legacy L Wagon (2WD / AT) with 200k miles died on the freeway, started again after cooling, then died for good. The mechanic I went to found a trouble code 11 - crank position sensor - no reference (eventually). The sensor reads correctly on an ociliscope all the way at the ECU connector. Is this a clear indication that the ECU is bad? Background: I am the proud owner of a 1990 Subaru Legacy L Wagon - 2WD AT. It passed the 200k mark a week ago. I am good about oil changes but have neglected other scheduled maintenance, other than the air & fuel filters. I have had some front end and drivetrain work but never any engine work. After about 175k, it started getting a little cold-blooded in the mornings occasionally, and in the last 10k or so it has started idling rough every ten cold mornings or so. The problem: On Sunday morning I was driving back home from a family event. I got gass and drove another 25 miles north, to about 35 miles south of the town my brother lives in, cruising up the freeway at 75mph, when without warning, I felt the power begin to go away and the pedal drop under my foot as I ascended a gentle hill. Looking at the tach, I saw that the engine speed was fluctuating very sharply, on a distinct downward trend. It was fairly warm in the car, as is my wife's preference. A few moments later the engine had stopped and I pulled to the side. It felt much like running out of gas - which I have never done in this car. There was no check engine light, no temp, nothing indicated odd. What I did: I waited a few moments and then tried to start the car again. The engine would turn over, and seemed like it wanted to take, but would stutter over a couple times and then die. One time I noticed that the "power" light blinked rapidly - I never noticed this again. I looked at what I could under the hood - no fuel leaks, no lost fluids, nothing obvious. I started to look for a tow truck after a while, but my particular location made a tow truck driver's trip 80 miles long to tow me to the next town, while mine was only 35. Once I had spent a while on the phone, I tried it again, and the car started without complaint. As I drove on cautiously, I found that the car hesitated a little, but seemed happiest at 3,000 rpm. I made it off the freeway but once I slowed down, it started hesitating and died about a mile down the road. I got my brother to bring his truck and tow me to his mechanic - one he'd recently began seeing with his Mazda. Monday morning when they looked at it, it started fine and showed no codes. They asked me to drive it a while, and I drove it 45 minutes before it started running very rough. I just made it back to the shop and let the mechanics listen to it before it died - never to start again. What the mechanics did: 1) The mechanics evaluated the fuel system first, and the fuel pressure test revealed that the pressure was fluxuating between about 20-30 when cranking. They determined that this was due to the pump cycling off due to a lack of the presence of spark. 2) Next they checked out the ignition system, and determined that the ignition coil was out of spec - resistance on the upper secondary pair was about 1.1, and the lower about 0.4 - and apparently were supposed to be at 0.7. He wanted to do more tests, but eager to get on the road, I let him work while I went to a junkyard and bought the coil from a running engine. Its resistances were off as well, and the junkyard guys told me that this is often the case even with working units. I figured for $35 I'd try it. But, it didn't help. 3) Next they replaced the "Igniter" / "Ignition module" because they weren't getting what they expected from it. Still no go. 4) Then he read the codes again. The computer - a Snap On "Modis" - indicated Trouble Code 11 - Crank Position Sensor - no reference. 5) He checked the sensor on a waveform both at the sensor and at the harness connector behind the intake manifold. Both looked good, but he procured a used-but-good sensor to try. When he changed sensor, fine powder of worn timing belt could be observed - I've known for a long time I need one, but have put it off. 6) He checked continuity from the harness connector to the ECU connector, which was good, as was the waveform at the ECU connector. 7) All those present visually examined the ECU and its pins and found nothing. So, I'm in $600 labor and about to be in a $200 used computer. Does his diagnosis sound reasonable?