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
- - - - -

Fuel shutoff failsafe?


  • Please log in to reply
15 replies to this topic

#1 xenongod

xenongod

    Eat, Live, Breath Subaru

  • Members
  • 266 posts
  • Denver, Colorado

Posted 23 February 2004 - 08:31 AM

Okay here's a long story made short. The gremlins living in my '81 GL AWD Wagon are on a rampage...so I replaced the battery...voltage regulator...and when I was replacing the alternator...I neglected to disconnect the positive on the battery and sparks flew for some reason. Ever since then...even after changing out the same parts...the car will run for 30 seconds then just shut down. I called S-Wings here in Denver and he mentioned that he 99.99% sure that there is a fusible link which is a failsafe just in case of a wreck or car fire that gave and now needs replacement. I checked most of my in-line fuses and don't see any fusible links broken...and Kevin from S-Wings said it is located above the gas pedal inside the dash. So...my question is this..am I looking for a link..or a common fuse? What color would the wires be and where could I find it? Anyhoo...thanks for the input...I really hope to get the wagon up and running. It has always been something trivial with this car...but usually simple...Thanks!!

#2 Skip

Skip

    Flatuous Blather

  • Moderator
  • 8,991 posts
  • Latrobe, Pennsylvania

Posted 23 February 2004 - 08:48 AM

The fuel pump on your car is operated by the voltage regulator.
I have never heard of this fail-safe "fusible link".
They, the fusible links, are located under the hood by the battery.
Your description sounds like the fuel pump gets the initial "run signal"
(pumps for a second or so when the key is first turned to the "run" position)
and possibly while you are cranking it to start.
This is normal and puts some gas in the fuel bowl.
BUT once the engine fires the fuel pump control circuit in the VR is not taking over as it should,
thus the car runs out of gas in the minute or so you describe.
The "sparks" may have let the smoke out of the FPCC (Fuel Pump Control Circuit)
I would put a hand on the fuel pump and feel if it's running after the engine fires.
Hope this helps


#3 The Scooby

The Scooby

    EJ Swap Junkie

  • Members
  • 1,752 posts
  • South Seattle

Posted 23 February 2004 - 11:41 AM

i would recoment picking up your car manual and making sure about that fusable link, it sounds like thats the problem. and sorry, skip but they are not always located by the battery.

we had a crysler at auto shop taht had this same problem as well as many others, but the link was actually in the wiring that ran to the tranny, it poped inline and the FSM didn't have it listed, so we had to trace the wire, and cut out the old and redo it with a new one, also re wrapping all of the wire along the way so it was not to be chafffed through be rubbin on the tranny.

good luck man, also check your fuel pump relay, sometimes that will go beserk and only let the car run for a few seconds and maybe a minute.

#4 Wasteland

Wasteland

    I am Evil Homer!

  • Members
  • 412 posts
  • Western Slope

Posted 23 February 2004 - 11:56 AM

I had the same problem with my '81 wgn. It ended up being the voltage regulator, I fried a new one on install and took it back, said it didn't work out of the box and got a new one. the second one fixed the problem. But I seem to remember a fuel pump relay the wiring diagram lists as being under the pass. seat. It had nothing to do with the problems I was having but you may check it, if only to rule it out.

#5 Skip

Skip

    Flatuous Blather

  • Moderator
  • 8,991 posts
  • Latrobe, Pennsylvania

Posted 23 February 2004 - 12:05 PM

Sorry Scooby I am afraid you have the word "fuse"
confused with the word "fusible link"
On our Subarus the fusible links are near the battery, the fuses, on the other hand, can be found under the dash.
As for the location of the relay and this mystery fuse?


#6 calebz

calebz

    Andys Coupe killed my cat

  • Administrator
  • 7,547 posts
  • Tacoma

Posted 23 February 2004 - 12:06 PM

sorry skip but they are not always located by the battery.



on an 80s subaru they are...unless someone moved it... Good thing this is a subaru in a subaru forum.. tracking down that chrysler fusible link would be a real bitch on his 81 GL wagon:D

#7 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,340 posts
  • Anchorage

Posted 23 February 2004 - 12:23 PM

The reason you got some sparks while you were working on the alternator is because the alternator's output lead is tied to the positive battery post. If the output post is grounded without removing a battery lead to isolate things then you saw what will happen. Always disconnect the battery when servicing the alternator.

There should be a fuseible link between the alternator and the battery. I would check that out if you haven't already since that is the path that got shorted. I can't remember where the links are located but they should be near the battery as someone meantioned already, in a small plastic box I think. I am more familiar with the EA 82.

I would recommend you get a service manual for your car. I have seen factory manuals on Ebay go for around $25 dollars. To me, that is a bargain and a service manual is a must have item.

I know nothing about a link above the drivers foot area sorry to say. Let us know what you find.

#8 The Scooby

The Scooby

    EJ Swap Junkie

  • Members
  • 1,752 posts
  • South Seattle

Posted 23 February 2004 - 12:48 PM

skip, ya i ment fusable link, and sorry then i am wrong, i assumed that they where throughtout the car like that crysler and my old 78 chevy, but subaru is different, and i should have thought of that before opening my mouth, thanks for the info.

caleb, that was pretty good, i left myself open for tha one. :D

Later,
Shean

#9 Meeky Moose

Meeky Moose

    Subaru Master

  • Members
  • 2,343 posts
  • Grants Pass

Posted 23 February 2004 - 12:57 PM

Originally posted by calebz
on an 80s subaru they are...unless someone moved it... Good thing this is a subaru in a subaru forum.. tracking down that chrysler fusible link would be a real bitch on his 81 GL wagon:D

:grin: :lol: :lol:

#10 Skip

Skip

    Flatuous Blather

  • Moderator
  • 8,991 posts
  • Latrobe, Pennsylvania

Posted 23 February 2004 - 01:08 PM

Shean, it's snow worry mate, like my sig. says
The more I learn....

I did look up the fusible links for an 83, (sorry earliest FSM I have) there is, as Glen says, a fusible link (FL2 the middle red one, I believe) which does connect the alt to the battery but the ignition is tied to this link and the car would have no juice and not evan try and start.

The issue here is Xeon says the car runs for 30 seconds and quits

Assumption that it is running out of gas, have you checked for spark when it quits or will it fire right back up (my previous sugg) and then run for another 30 seconds and quit?


#11 xenongod

xenongod

    Eat, Live, Breath Subaru

  • Members
  • 266 posts
  • Denver, Colorado

Posted 24 February 2004 - 08:06 AM

To answer some questions and doubts...I forgot to mention that the fusible link between the battery and alternator did give way and I replaced it with probably the last new one ever...thanks again to S-Wings. The link is basically two wires with two connectors...also noticed that my wires are rusting from the inside out. The car will fire right back up and then do the 30 second run then quits. I haven't located the fuel pump yet...but I think it is on the passenger rear wheel well area and will check it when I have time. Another weird thing...some months ago after the gremlins ran amuck for a while...I purchased a new voltage regulator from NAPA...on initial startup...the new VR smoked and almost caught fire...so I put the old one back in and had no problems for a while until the whole new quirk came into play...oh btw..the employees at the one on Tejon here in Denver are complete *******s and accused me of putting it in wrong...which in near to impossible with one connector and two other wires...friggin' jerks there. The voltage regulator in there now is one from a '82 Hatchback...the numbers are the same on both of them..so I figured it would work...but apparently not. I am completely befuddled. I have over 13 years of working on cars..and I do know that whenever working on electrical or even mechanical areas...that you are supposed to disconnect the battery...but as I said...I neglected to...everyone makes mistakes...eh? Anyhoo...thanks again...and I do have service manual...even have the HTKSA manaul...but it not much help sometimes when trivial things like this occur.

#12 xenongod

xenongod

    Eat, Live, Breath Subaru

  • Members
  • 266 posts
  • Denver, Colorado

Posted 24 February 2004 - 08:17 AM

since the new VR from NAPA didn't work...and I don't have the 60 bucks to buy one...does anyone have one at a good price and condition so I may try another VR? One last note...really weird...the wires and connectors on the alternator were not connected when the sparks occured...I was pulling it out when a big blue spark came shooting at my face. My wife also mentioned a couple days earlier that she noticed a smell like wires burning and then the car died and I put in a new battery and it got me home...but after a while...it would die and found out the one-year old alternator from Autozone had gone bad...thank God for lifetime warranties. So...while replacing it in their parking lot....the big mystery started. So...all in all....the wagon is in beutiful mechanical shape...but probably needs a very thorough electrical overhaul...you think?

#13 Skip

Skip

    Flatuous Blather

  • Moderator
  • 8,991 posts
  • Latrobe, Pennsylvania

Posted 24 February 2004 - 08:55 AM

This guess comes to you from reading about it happening here on the board...
The auto parts store (NAPA?) may have given you an alternator with a built in voltage regulator. You put it in the the parking lot and...
as I said this has happened.
Please reread my original post about why it is starting and then dies.
I will not hazard a guess about

I was pulling it out when a big blue spark came shooting at my face.

a message from Pleiades??
I do not know how serious you are about keeping it stock
but maybe a rewire for 83 or newer with a internal VR is in the cards.
The FPCU (Fuel Pump Control Unit) from a newer model would be ness.
if you wanted the fail safe fuel pump control.


#14 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,340 posts
  • Anchorage

Posted 24 February 2004 - 11:13 AM

When you say your wires are rusting, are they near the battery where acid can get into them and corrode them?

Since you have a manual this should make things a lot easier to find the trouble. Do you have a voltmeter also so you could check the voltage getting to the FPCU that Skip mentioned? The FPCU may be under the passenger seat. I would check the wiring diagram see where the power comes from and into the FPCU. Check to see if the power is still ok to the input after it shuts down. This should eliminate a feed wire problem. If that is ok, then it may be a problem with the signaling into the FPCU. I am not familiar with your unit but I know some FPCU units require the pulsing signal of the ignition system so it knows that the engine is running and to keep the pump on. I can only think that there is a delay in the circuit and if there is no ignition signal, the delay circuit drops out the power to the pump after a preset time.

#15 Skip

Skip

    Flatuous Blather

  • Moderator
  • 8,991 posts
  • Latrobe, Pennsylvania

Posted 24 February 2004 - 11:26 AM

My fault I should have not confused the issue.

Glen, I believe since he has an 81 he has no Fuel Pump Control Unit, these were in cars after they went to the alternators with the built in voltage regulators (83 through ? intro of FI)

His fuel pump control is handled by the external voltage regulator.

This era 81,82,83 has some strange ways of controlling the fuel pump.
We need a definitive chart, as was purposed before,
to refer to when these problems crop up


#16 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,340 posts
  • Anchorage

Posted 24 February 2004 - 11:57 AM

A voltage regulator controlling a fuel pump? That's a new one on me. My earliest experience with Soobs was my new '83 wagon but it gave me so little trouble I didn't work on it much.

Since that's the case, is the VR supplying the power to the pump or is it just supplying a control signal to a relay or something similar for the pump? We need to see where the power is getting cutoff using a meter or test light I think.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users