Jump to content


Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse
 

Photo
- - - - -

1987 XT: No spark, except one spark while turning off? WTF?


  • Please log in to reply
43 replies to this topic

#26 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 01 May 2011 - 09:45 PM

I tore out the passenger seat, the sill plate and the carpet, and could not find any crimped connections at all. Am I missing something?

I really want to get this car running!

#27 naru

naru

    1000+ Super USER!

  • Members
  • 1,828 posts
  • under the bridge

Posted 01 May 2011 - 10:30 PM

You need to unwrap the harness,IIRC.

#28 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 01 May 2011 - 10:33 PM

OK I'll go back out there in a minute and start tearing the tape/foamy crap off and investigate.

The ground under the passenger seat carpet looked REALLY nice, like it had been recently cleaned or something. It was also a tad loose, so I tightened it. Made no difference, of course.

I'm really beginning to think that digging through the wiring is not going to fix the car, I think this thing's destined for the junkyard, a new $200 windshield later :-\

#29 naru

naru

    1000+ Super USER!

  • Members
  • 1,828 posts
  • under the bridge

Posted 01 May 2011 - 11:09 PM

Believe this is the thread I was thinking of.
http://www.ultimates...=injector trunk

#30 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 01 May 2011 - 11:22 PM

I took the tape off the wiring harness and found two crimped connections. Problem? They look CLEAN. Like they were repaired at some point in time, absolutely clean. Ahhh :mad:

#31 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,342 posts
  • Anchorage

Posted 02 May 2011 - 02:17 AM

Check the fusible links for a loose connection and check the pins on the ECU I stated earlier.

Edited by Cougar, 02 May 2011 - 05:52 PM.


#32 naru

naru

    1000+ Super USER!

  • Members
  • 1,828 posts
  • under the bridge

Posted 02 May 2011 - 01:34 PM

I took the tape off the wiring harness and found two crimped connections. Problem? They look CLEAN. Like they were repaired at some point in time, absolutely clean. Ahhh :mad:


OK,so probably not those ones.Sounds like they are injector outputs anyhow.

A more systematic diagnosis w/the voltmeter is required when shotgun repair methods fail.It will save time and money.

Harness connection points,ignition relay contacts and fusible links are all on the suspect list.Measure at ECU to see what is missing.

#33 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 02 May 2011 - 04:48 PM

OK, gonna wrap the wires back up, put all that back together, and get crackin' on the ECU pinout voltage check.

#34 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 02 May 2011 - 07:01 PM

Pin 24 is getting zero volts, but the two others are getting 12V.

And since pin 24 comes from the ignition switch... maybe that's it?

#35 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,342 posts
  • Anchorage

Posted 02 May 2011 - 07:59 PM

You're hot on the trail now. Check the power input to the ignition switch.

Edited by Cougar, 02 May 2011 - 10:40 PM.


#36 naru

naru

    1000+ Super USER!

  • Members
  • 1,828 posts
  • under the bridge

Posted 02 May 2011 - 10:49 PM

Pin 24 is getting zero volts, but the two others are getting 12V.

And since pin 24 comes from the ignition switch... maybe that's it?



According to my diagram,pin 24 is only hot when the ignition switch is in the start position.

#37 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 02 May 2011 - 11:44 PM

The ignition switch is getting 12V to it. Well, one of the four wires gets 12V, the others do not. So should I check for voltage at pin 24 while cranking then?

I also noticed one of the four relays behind the radio area was slightly hot while messing with the ECU plugs.... but no clue which is which...

Thank you Cougar and Naru for helping me out here, this is a PITA!

Edited by misledxcracker, 02 May 2011 - 11:47 PM.


#38 naru

naru

    1000+ Super USER!

  • Members
  • 1,828 posts
  • under the bridge

Posted 03 May 2011 - 12:11 AM

Might as well.I suppose if it still had 12V after startup,the engine might flood.

#39 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 03 May 2011 - 09:44 AM

I'm trying to figure out what the deal is with those four relays in the dash and possibly figure out a way to test them.... I'm also trying to figure out which other wires I need to start checking out.

I'll just hook up a test light to pin 24 with the ECU unplugged and see what happens, I'm sure you're right though, it'll probably come on while I'm "cranking" the motor...

Any other ideas/suggestions welcomed immensely; I am gonna start trying to decipher this XT FSM the best I can.

#40 AWD TURBO!

AWD TURBO!

    USMB is life!

  • Members
  • 205 posts
  • vancouver

Posted 03 May 2011 - 11:02 AM

well i had the same problem the crank pickup unit under the metal plate in the disturber cap went bad on mine there junk yard parts there not cheap new

i would be cranking the fule pump primed win key on but didn't run win i stopped cranking it would spark

all so see it your gutting power at the coil win cranking

#41 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 03 May 2011 - 11:22 AM

I know how to swap the CAS out of the distributor. Subaru is not the only one that uses these rather specific CAS units.... Mercury Villagers and Isuzu Troopers do as well.

Wow, my Jag does not have a single issue, yet my XT is parked and inoperable..... Should be the other way around! 91 octane and a straight 6 really kills me on gas!

#42 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,342 posts
  • Anchorage

Posted 03 May 2011 - 12:05 PM

According to my diagram,pin 24 is only hot when the ignition switch is in the start position.


Thanks for the notice on that Naru. I wasn't aware of that.

It would be good to verify that voltage is getting to that point in the START position. We can rule out any power issues to the ECU as the source of the trouble then.

#43 misledxcracker

misledxcracker

    Guy no one ever answers

  • Members
  • 846 posts
  • Bullhead City

Posted 04 May 2011 - 06:28 PM

Checked that pin, Naru you were absolutely right.

Car runs and drives now. What did I do? Trusting my instincts to a point, I went and yanked another CAS out of an Isuzu Trooper (third CAS) and the XT fired up no problem!

Thank you Cougar and Naru for helping me out, at least now I know a lot more about wiring and such :grin:

Now watch the Jag take a dump on me.... LOL

#44 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,342 posts
  • Anchorage

Posted 04 May 2011 - 11:41 PM

Good deal. Glad to hear you finally got it running. Defective replacement parts are a bad thing and can cause confusion like this. You kind of end up chasing your tail.

You're welcome for the help.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users