88RxTuner Posted January 29, 2009 Share Posted January 29, 2009 Okay, guys... Little background. 1988 RX, TD04 swap, TMIC, Went mobbing...in the rain. Came home, no problems, parked and shut 'er down. Went out next morning, no crank, no dash lamps, etc... found the main fusible link blown in the engine comp't. Diagnosed cause, apparently in my 'mobbing' episode I had rubbed that wire through and shorted it out. Repaired wiring as necessary, installed new fuse link, now it cranks all I want but no spark. Here's where I've been already: **Diagnosed dizzy. Both sensors work correctly. I even took the time to swap my spare dizzy in, to no avail. Still doesnt spark. **Replaced coil, just to be safe.. I had a new spare sitting around, and figured it couldn't hurt. **Verified wiring harness, no shorts to ground or power between dizzy and coil. Everything seems to be intact. **Checked and cleaned all engine-bay grounds. One other things, key on code 11 flashes on ECU/ O2sensor LED... I'm no amateur at fixing these things, and this has got me SO FLIPPIN FRAZZLED I just want to sell it... but I know if I sell it I'd have to kick my own arse, cause it took me 5 years to find the thing... Any advise?? 88RxTuner Link to comment Share on other sites More sharing options...
Yo'J Posted January 29, 2009 Share Posted January 29, 2009 silly wire rub on some harness somewhere? I was blowing fuses like a fool trying to figure out my rear lights once when I found a rub under the radiator, a melted plug bank just above it and a single wire by the muffler, not that yours would be there but all mine were fine until I would hit a puddle then the next one would go. It was one at a time. Just a thought. Link to comment Share on other sites More sharing options...
Turbone Posted January 29, 2009 Share Posted January 29, 2009 Check all the fuses in the cab. A couple of those are for the ign relays. Link to comment Share on other sites More sharing options...
88RxTuner Posted January 29, 2009 Author Share Posted January 29, 2009 Been there, done that... All Cab fuses are a-ok. On initial diag, found the IGN_COIL fuse to be blown, replaced with same fuse, has not blown again. Have good power to coil. Tested output of sensors at Dizzy... Everything checks out OK... This is why I'm confused!!!!! lol Dammit!! Link to comment Share on other sites More sharing options...
XT6 Magic Posted January 29, 2009 Share Posted January 29, 2009 Does this system use the power transistor mounted on the ignition coil? Have you tried replacing that as well if it does? Link to comment Share on other sites More sharing options...
88RxTuner Posted January 29, 2009 Author Share Posted January 29, 2009 Not familiar with "power transistor mounted to coil".... I have removed the coil and bracket, found one 2-wire round connector going to coil and one 2-wire "T" connector going to small round thing under coil that looks like it's riveted to the coil mounting bracket. PER Trouble tree diagnostics, everything checks out at these 2 connectors... but I could be wrong. Do you know something I dont??? (that would be great, by the way...) 88RxTuner Link to comment Share on other sites More sharing options...
XT6 Magic Posted January 29, 2009 Share Posted January 29, 2009 The "small round thing" riveted to the coil bracket can cause no spark if it fails. I assumed it was a power transistor but I could be mistaken. I had one fail on recently on my wagon. Good Luck, hope you get it running soon. Link to comment Share on other sites More sharing options...
Frank B Posted January 29, 2009 Share Posted January 29, 2009 If you burned up a fusible link, chances are it blew a fuse, or melted a relay somewhere too. With that ignition fuse blown I'd trace the circuit, maybe there's another fuse or fusible link that's been added. Get a spare relay, or use your AC relay, and just start swapping out one by one trying to start along the way. Does the engine crank fast or slow, maybe the battery is weak and isn't enough to fire up the ignition??? Add a few ground wires while your in there, from intake to case(block), intake to body. Link to comment Share on other sites More sharing options...
Cougar Posted January 29, 2009 Share Posted January 29, 2009 You stated you have good power to the coil. Did you check to see if there is voltage getting to the minus lead of the coil? You should have voltage there also. If you do, then I would suspect the ignition amplifier is causing this trouble. It is the transistor mentioned earlier. It may be what caused the shorting problem you had. Link to comment Share on other sites More sharing options...
88RxTuner Posted January 30, 2009 Author Share Posted January 30, 2009 (edited) Double checked all fuses, ok after replacing the one mentioned above. Wouldn't a bad fuse or relay prevent power to the coil and to the dizzy? Both have appropriate power according to the trouble tree. As stated, removed, cleaned and re-installed all engine bay grounds just to be sure, and ohmed all grounds to the battery with less than 1 ohm resistance on any/all of them. YES, I have power on both sides of the coil when assembled. I have 11.4 volts on the black/ white wire ONLY to the + side when disconnected, and when assembled I have 11.4v at the + and 11.3v at the - side. Cked the voltage drop on the - side, fluctuates from 11.3v to 0v with turning of the dizzy.. is this normal for proper operation? Followed the trouble tree diagnostics from the manual and all indications pointed at the dizzy, which I traded out for known good dizzy ( which has the same bench test meter readings as the old one, after all) and still no start. Sounds like this ignition transistor amplifier thingy may be the issue.. this is new territory for me, so any advice is well recieved... Is there an easy fix for the amplifier? Thanks for your replies!! 88RxTuner Edited January 30, 2009 by 88RxTuner Link to comment Share on other sites More sharing options...
presslab Posted January 30, 2009 Share Posted January 30, 2009 Man it's problems like these that make it nice to have a scope. I use one meant for electronics but my friend sells the Snap-On Modis. My girlfriend's car had a bad coil (arcing on the secondary) and the Modis had an example graph showing normal behavior and the bad coil was a bit off from that. Pretty cool! Anyway sorry for the OT. Maybe you can find someone who has a scope of some type to look at it. I'm guessing the ignition amplifier too, although changing from 11.3 to 0 by turning the disty means the amplifier is working at least a little. You can't repair it if bad, you just replace it. Shorting out the wires like you had and arcing creates large voltages that can fry electronic things. Link to comment Share on other sites More sharing options...
88RxTuner Posted January 30, 2009 Author Share Posted January 30, 2009 So I noticed... I'm hoping it didn't fry the little electronic things all the way up to the ECM... Thanks for your input, trying to convince my buddy to let me use his MODIS... he's somewhat reluctant to let his 8,000 dollar baby out of his sight. 88RxTuner Link to comment Share on other sites More sharing options...
88RxTuner Posted January 31, 2009 Author Share Posted January 31, 2009 Is there a way of testing this "amplifier" transistor? I went to the recylclers today, and unfortunatley could not find a single other subaru with this type of ignition coil bracket, with the amplifier transistor riveted to it... No Luck with the MODIS... he wont let it out if the shop. 88RxTuner Link to comment Share on other sites More sharing options...
Cougar Posted January 31, 2009 Share Posted January 31, 2009 To test it you should be able to check it with a DVM using the diode test function. I think it is a NPN transistor. Skip may know the ID number for it. If you just purchased a replacement transistor it wouldn't cost you much. Link to comment Share on other sites More sharing options...
XT6 Magic Posted January 31, 2009 Share Posted January 31, 2009 They are plentiful in the Seattle area. I'll be happy to pick one up and mail it to you. Give me a couple days to get back out to the yard though. -Jeff Link to comment Share on other sites More sharing options...
88RxTuner Posted February 3, 2009 Author Share Posted February 3, 2009 That'd be awesome... I have scoured the wrecking yards around here (subies are hard to come by in the desert...) and found some promising donors for the future, including one unmolested complete turbo engine, but none of them have the damned transistor/amplifier type ignition coil bracket... Not to mention the parts houses around here havent the slightest CLUE what I'm talking about, and I'm about 150miles from the nearest radio-shack. I'm guessing it's specific to my model/year? I'd gladly reimburse you for the part, and your time if you'd like... Link to comment Share on other sites More sharing options...
XT6 Magic Posted February 3, 2009 Share Posted February 3, 2009 (edited) OK, I have one for you now. If this looks correct send me a PM and I'll get it to you. Edited February 4, 2009 by XT6 Magic Link to comment Share on other sites More sharing options...
88RxTuner Posted February 12, 2009 Author Share Posted February 12, 2009 Correct bracket, correct plugs... but mine doesn't have the nifty little foamy pad on the back!!! lol PM sent... Sorry it took so long. Link to comment Share on other sites More sharing options...
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