Zootal

So the plot thickens . It has got to the point where with the key on and engine NOT running, I here this clicking noise from under the hood and the tach jumps. Look around a bit and I realize the fuel injectors are firing along with the tack jumping. I unplug the cam sensor, no change. Unplug the crank sensor, it stops! Remove crank sensor, examine. Has buildup of crud on the bottom, but idk. Plug it back in, and the problem does not start up again. Now I gotta wonder, was it a bad connection at the plug, or is the sensor bad? Shop for sensors. Most after market sensors have the wire connector on the sensor itself. However, this sensor does not - it has about a foot of wiring coming out of it, with a plug on the end. Sensors with plug on sensor, which don't look right - $20-$40. Sensors with the wire attached and a connector at end of wire - $200+. Ouch. Did they put two different sensors on this? And the sensor is under the alternator, no need to pull timing belt. Not sure why book says to pull timing belt...

Yah, I thought of that. I'm hoping it isn't cam/crank sensor, as IIRC you have to pull timing belt covers to get to it. I got finals next week so won't be able to do anything until next weekend, but I'll post my results here when I do get a chance to work on it.

That kinda sorta makes sense, as it would effect the tach and cause it to stumble at idle. I would guess at ignitor, as that would cause the tach to jump even with engine not running. Whatever this is, it acts up without the engine running, meaning there is no HV going through the coil - unless the ignitor is tickling the coils, which is also possible......hmm.... Coils are easy to find, I see after market "ignition control module" for about ouch $185 autozone, $40 amazon. I hate to throw parts at this, but that combo does sound like a good place to start...I wonder why autozone wants so much for the part? I think I'm going to push it into my garage and take a closer look at effected parts, maybe something obvious will stand out that I missed before... And hope it's not the ecu cause those are $300 plus **sobs**

1994 Subaru Legacy. FWD. 4dr. Non-turbo. 230,000 miles or so. Normally purrs like a kitten. Symptoms: engine will idle, but miss intermittently, every few seconds or so. Sometimes it's better, sometimes it's worse, sometimes it will stall and sometimes it won't idle at all. When it's acting up, it is hard to start. Has good power otherwise, no noticeable problems at higher engine speed. It's been doing this for weeks, but today it got so bad that it won't idle half the time and now my wife refuses to drive it (I don't blame her). Here is where it gets interesting. With the key on and engine *off*, the tachometer jumps every second or so. It will jump up to 500-1000 rpm point, then drop to zero. The frequency of this is ever second or three, and is the same frequency that it stumbles at idle. The check engine light is *not* on. This eliminates a whole slew of possibilities, and narrows it down to some weird electrical problem. It doesn't get worse when I hit a bump or slam the door (my old chevy vega would stall if I slammed the door, but that is another story). Anyone have experience with this model and recognize these symptoms? I'm not sure what to do other than check the various electrical connections and think about replacing the ecu. The battery is fully charged and is fairly new, it cranks very well. Alternator is fairly new. It charges just fine when the engine runs. AFAIK there are no obvious mechanical problems, nothing makes noise, it normally just purrs and runs fine. Until this started happening. With the engine OFF and key ON, the tachometer jumps, but the lights do not flicker, and no other lights or instruments act up.