February 28, 201412 yr If you still have the timing covers off check the reluctor fins on the crankshaft and make sure none of the tabs have broken off. This has happened to some folks with this kind of problem. If they are okay then it would seem the ECU has to be at fault. Yeah....at this point I'm gonna say it's gotta be the ECU. That's what the FSM flow chart would lead to with all the wiring being tested. WAIT! Did you test for any continuity BETWEEN each wire and the others.....and maybe check to ground too. There should be none.
February 28, 201412 yr Could be the ECU or loose connection at the pins for the igniter or coil. Have you tried the wiggle test? Wiggle the wires at the coil and the igniter with the engine running to see if it starts firing right.
February 28, 201412 yr Some other tests you could make to verify the ECU as the trouble is to compare DC voltages on the two wires going to the ECU while the ignition is turned on, using ground as reference. See if they are the same readings. Also check the two wires with just the ECU connected to the wires and do a diode function test referenced to ground and swapping the probes to check both directions of the current, with the ignition switched off. See if those readings compare to each other. They should be close to the same readings if things are good inside the ECU.
March 1, 201412 yr Author OK wheel here's an update. Bought a coil. Didn't help I don't think. BUT.... If I take a test light, put the alligator clip on the POSITIVE of the battery, and touch the probe to the YELLOW/BLUE pulse wire at the ignitor, then remove it (essentially putting 12 volts on that wire then removing it) cylinder 1/2 misfire goes away! But only for 2-3 seconds, then those cylinders fail to fire. Touch 12v to that wire, then remove, misfire gone for 2-3 seconds. What in the hell!?!?!?!?!?! Edit**** The longer I hold 12v to that wire, the longer the misfire stays away. I held 12v to that wire for about 20 seconds and it ran great for like 35 seconds!!! Edited March 1, 201412 yr by subenoob
March 1, 201412 yr That's the signal wire from the computer which should have about 1-3 volts on it when the engine is running. By supplying voltage to the pin via the test light, you're charging a capacitor either in the ECM or the Igniter which is then opening and closing the ground circuit for the coil. (The igniter controls the ground side of the coil) The longer you hold it there the longer the capacitor charges. Once the capacitor discharges, there is no power to open and close the ground for the coil, so you get no more spark. You'll want to check for voltage on that pin at the igniter. If there is less than 1v, check voltage on that wire at the ECU. Should have between 1 and 3 volts. If you have no voltage at the ECU, wiggle the connector while testing. If still nothing, turn the engine off, unplug the ECU connector and check for corrosion on the pins. If the pins are clean, probably need a new ECU.
March 1, 201412 yr I think you have pretty much proven that the ECU is at fault. I suggest you check to see if you can get a replacement from a salvage yard at a real reasonable cost.
March 2, 201412 yr Author Voltage on the yellow/blue wire at the ignitor is at around 0.06-0.09. It kinda fluctuates. Hard to believe the ECU is bad from the last time it was driven (6 months-ish) to now from just sitting. I also have noted the door locks going crazy at random times. Not all the time but sometimes...
March 2, 201412 yr If it has just been sitting then it could have water damage. Especially if it got snowed on and was never cleared off. Power door lock timer problems are common.
March 2, 201412 yr How do the two voltages of the two wires compare to each other? If the ECU is okay they should be close to equal. I would suspect dirty switch contacts for the door lock issue. The driver side is usually the best suspect.
March 3, 201412 yr Author Today voltage on the yellow/blue wire was 0.18 and the yellow/violet wire next to it was 0.35/8 ish
March 3, 201412 yr Even though the voltage differences you read are small I think it indicates the problem is with the ECU. The two sides are basically mirrored circuits and should have the same readings voltage wise and ohm wise.
March 16, 201412 yr Author Looking around I see different ECU's for 95 legacy. I've seen some that say "R4" "C9" and "2D". Mine says "2D". I take it if I get a new one it should also say 2D? Does it matter? Thanks
March 16, 201412 yr I don't think it matters much as long as the connectors match up. Things like a turbo option, engine size, and transmissions may come into play. There are places that sell rebuilt units that you could refer to about that.
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