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
- - - - -

PKmobile won't start!!!! Fuel Pump fuse/relay?


  • Please log in to reply
22 replies to this topic

#1 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 07 October 2004 - 04:42 PM

:(

drove home last night, completely normally.

I got up this morning, and no start. Cranks over quite well. I went home at lunch to check it out and there is apparently no fuel reaching the engine, the front fuel filter is dry. The rear one has lots a fuel in it, there is a quarter tank of gas. I pulled the fuel pump off and hooked it up to a spare battery, and it does its thing, so I checked the power at the fuel pump and there is no juice. I had the ignition switch all the way on, there should be power at the pump, yes? no? My BMW bike has a relay that activates the fuel pump when the starter turns, but this thing is a lot older.

(1984 GL wagon)

Is there a relay? All the fuses look good, is there a fuse somewhere else?

any other ideas?

Pulllleeeeeeaaase?

Thanks for any help,
Mendo

#2 TheSubaruJunkie

TheSubaruJunkie

    Subaru Sober since 2010 :(

  • Members
  • 1,908 posts
  • Sacramento

Posted 07 October 2004 - 08:32 PM

From my understanding our fuel pumps only operate while the alternator is being turned. I tested mine when it was failing and replaced it. Replacing it fixed the problem for a week until it failed again. I found that it wasnt getting juice, or was getting it but then could cut power. I got tired of tracking the problem down, and just hard wired the pump to a switch. That took care of the problem for good. Also a great theft deterant.

-Brian

#3 P K

P K

    Devil Dog Liaison

  • Members
  • 1,171 posts
  • Omicron Persei Diego

Posted 07 October 2004 - 08:36 PM

I think it's a total. Maybe you should sell it back to me. :D

Sorry to hear, Dave. So it 's no electrical to the pump? Somewhere I read that Sube's fuel pump get their voltage form the voltage regulator - check those connectors and/or relay. Good luck. r/PK

#4 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 07 October 2004 - 08:54 PM

Another symptom?

Even if I pour gas straight into the carb it won't fire...so the ignition and fuel systems go out at the same time? When I got home last night, I drove into the drive, parked, shut down the engine, and then noticed the windows weren't up, so I turned the key to ignition to get juice to the electric windows and rolled them up, and then turned off the ignition. Sounds like a fuse somewhere to me, the fusible links all check out, the fuses in the fusebox all check out.

what the fsck?

if it was a windows computer i'd reboot the peckerhead.

sorry PK, not yet!

:grin:

#5 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 07 October 2004 - 09:02 PM

OK, no spark from the coil. No juice to the fuel pump.

did my computer just die? The alternator is spinning, it cranks over just fine.

I disconnected the battery, and will leave it off for an hour or so.

maybe it needs a power recycle.

Perplexed in Mendocino :-\

#6 Guest_taprackready_*

Guest_taprackready_*
  • Guests

Posted 07 October 2004 - 09:16 PM

I'm not sure about 84, buy my 82 Brat runs great without the computer. And my 82 wagon will run with the comp unhooked as well. I would continue to look for something very simple.

Bill

#7 TheSubaruJunkie

TheSubaruJunkie

    Subaru Sober since 2010 :(

  • Members
  • 1,908 posts
  • Sacramento

Posted 07 October 2004 - 09:28 PM

Dave. I wouldnt worry about your fuel problem right now until you get your spark fixed. After your coil is putting out power then worry about the fuel. You might find the problem to be the coil or spark the whole time.

-Brian

#8 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 07 October 2004 - 10:55 PM

considering that i drove it to where it is, and the fuel/ignition took a dump at the same time, i think troubleshooting the ignition is a waste of time. i do have a spare coil, PK put a hotter one on there which has worked perfectly. The wires, cap, and rotor are less than a year old. It always starts, even after washing the engine off.

I can stuff the spare coil in there tomorrow.

Brian: I am good to go for all day Tuesday the 19th off, so if the wagon is going I'll stop by then.

D

#9 P K

P K

    Devil Dog Liaison

  • Members
  • 1,171 posts
  • Omicron Persei Diego

Posted 07 October 2004 - 11:00 PM

On my Brat the fuse blew in the engine bay - fusable link?. Replaced and it kept blowing everytime I tried to start it. Turned out to be the alternator was shorted (or regulator inside ). Dunno?

#10 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 07 October 2004 - 11:03 PM

hmmmm

the alternator was replaced about 8 months ago with a rebuilt one. would that kill the fuel pump and ignition if the regulator went out?

the voltage regulator is built into the alternator on these years.

hmmmmm

yo Qman, you have a suggestion?

#11 rallyruss

rallyruss

    Subaru Master

  • Members
  • 1,653 posts
  • San Jose CA

Posted 07 October 2004 - 11:23 PM

I would need to check a diagram but on my old 85 GL the fuel pump was powered by the ecm with no realy. probably one of the dumbest things I have seen subaru do.

Its ghetto but I wired it to coil positive.

it sounds as though you must have some kind of blown fuse, fuse link, connection?

as usual check all powers and grounds. I will try to look at a diagram for you later.

#12 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 07 October 2004 - 11:37 PM

I reconnected the battery, no go.

I also feel it is something easy, a fuse/link/relay

but heck, been wrong before!

d

#13 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,322 posts
  • Anchorage

Posted 08 October 2004 - 09:39 AM

I think the problem you are having with the pump is due to the fact that the ignition is not working. If there is no ignition pulses being sensed then the fuel pump circuit is shut down. This is done for safety reasons.

Have you checked all your fuses for a problem there? Also check the distributor and see if you have voltage getting to both sides of the coil with the ignition on, and if you get pulsing voltage on the minus side of the coil while cranking the engine. If you don't see any pulsing and have voltage, then you need to look at the distributor area for a problem with the pickup sensor.

#14 Sweet82

Sweet82

    Elite Master of the Subaru

  • Members
  • 3,266 posts
  • Salt Lake City

Posted 08 October 2004 - 09:50 AM

I had a similar problem when I was building "Summer". Everything went back together just fine and it fired up great. Shortly thereafter it wouldn't start?
I traced the problem to the fuel pump. After replacing the pump, I found it still wouldn't start. I then traced the problem to no power at the pump. This was because the "Black Box" (Fuel Pump Control Unit) went bad...for no apparent reason...It quit sending power to the pump.

You might want to check this out on yours?

For what it's worth...
Glenn
82 SubaruHummer---Summer
01 Forester

#15 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 08 October 2004 - 09:55 AM

I had a similar problem when I was building "Summer". Everything went back together just fine and it fired up great. Shortly thereafter it wouldn't start?
I traced the problem to the fuel pump. After replacing the pump, I found it still wouldn't start. I then traced the problem to no power at the pump. This was because the "Black Box" (Fuel Pump Control Unit) went bad...for no apparent reason...It quit sending power to the pump.

You might want to check this out on yours?


Would this also kill the ignition system? Where is the fuel pump control unit located? Thanks!

#16 Sweet82

Sweet82

    Elite Master of the Subaru

  • Members
  • 3,266 posts
  • Salt Lake City

Posted 08 October 2004 - 10:29 AM

I'm not sure what it does? :confused:
I know it controls the fuel pump power and the choke on the carb.

It's a black box 1982 (Light blue on later years 1984?) that mounts to the side wall of the car near the hood release. I think it has a six prong wire connector. I tested mine using a volt meter and the wires that run to the fuel pump. No Volts!

I think it uses a signal from the coil to know how often to pump but I'm not sure if it's dependent on the ignition system or if it is able to kill the ignition system?

Someone here will know...

I'm still concerned about the spark thing...

Good Luck
Glenn
82 SubaruHummer
01 Forester

#17 rallyruss

rallyruss

    Subaru Master

  • Members
  • 1,653 posts
  • San Jose CA

Posted 08 October 2004 - 12:56 PM

I think the problem you are having with the pump is due to the fact that the ignition is not working. If there is no ignition pulses being sensed then the fuel pump circuit is shut down. This is done for safety reasons.

Have you checked all your fuses for a problem there? Also check the distributor and see if you have voltage getting to both sides of the coil with the ignition on, and if you get pulsing voltage on the minus side of the coil while cranking the engine. If you don't see any pulsing and have voltage, then you need to look at the distributor area for a problem with the pickup sensor.


cougars are smart kritters. thats a verry logical assesment. I will have to second it. makes sense. chase the ignition problem first.

#18 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 09 October 2004 - 10:17 AM

Well, I have voltage (12v) on either side of the coil, but I am off on a motorcycle ride this weekend and the beast will have to sit there. Didn't get a chance to check for the pulsing since it was starting to pour down rain.

Back at it tomorrow afternoon

thanks, everyone.

david

#19 Mendodave

Mendodave

    USMB is life!

  • Members
  • 127 posts
  • Little River, California

Posted 11 October 2004 - 09:29 PM

OK, fixed.

My apologies, Brian, you were correct. Fix the spark, the gas comes later. There was no pulsing on the negative terminal on the coil, as Cougar suggested I check for...so, I yanked the distributor out of my spare engine, stuck it in there, and voila! Spark, Gas, Ignition!

reminds me of a t-shirt I saw

Suck, squish, bang, blow, that's what makes a thumper go!

Thanks for all the support, everyone!

#20 NV Zeno

NV Zeno

    Elite Master of the Subaru

  • Members
  • 3,031 posts
  • Ponderosa Ranch, Nevada

Posted 11 October 2004 - 11:34 PM

Cool beans, Dave.

Glad to hear you got it going again, and at little or no cost..WOOT!

#21 rallyruss

rallyruss

    Subaru Master

  • Members
  • 1,653 posts
  • San Jose CA

Posted 12 October 2004 - 01:12 AM

OK, fixed.

My apologies, Brian, you were correct. Fix the spark, the gas comes later. There was no pulsing on the negative terminal on the coil, as Cougar suggested I check for...so, I yanked the distributor out of my spare engine, stuck it in there, and voila! Spark, Gas, Ignition!

reminds me of a t-shirt I saw

Suck, squish, bang, blow, that's what makes a thumper go!

Thanks for all the support, everyone!


see I told you cougars were smart:cool:
glad you got it goin. good on ya.

#22 TheSubaruJunkie

TheSubaruJunkie

    Subaru Sober since 2010 :(

  • Members
  • 1,908 posts
  • Sacramento

Posted 12 October 2004 - 01:56 AM

WOOHOOO!!! I WAS RIGHT :)

:clap: :clap: :clap: :clap: :clap:

Im just glad you got it running again. I dont think my tires are going to be ready on the 19th. My wagon hasnt moved in months.

-Brian

#23 Cougar

Cougar

    Elite Master of the Subaru

  • Members
  • 6,322 posts
  • Anchorage

Posted 12 October 2004 - 10:38 AM

Your welcome for the help David. Glad your back on the road again.




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users