Got answers last time, need some help again. - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Electrical
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 07-23-2006, 02:41 PM
Registered User
 
Join Date: Sep 2005
Location: Michigan
Posts: 6
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Got answers last time, need some help again.

I had posted awhile back for my 87 Bronco II problems and Doc helped me out..well its time for some new questions and some new answers for the same truck lol. A few months back i was leaving my friends house and the truck went about 3 houses and then just died, well it wouldnt start at all. It would turn over just not fire. Well i checked it for spark and that was fine..well after i had it taken home on a flat bed i did a little more digging and found that the Fuel pumps were not running. I hit the Innertia switch and nothing. Checked the Fuel pump relay and thats fine. I changed the high pressure fuel pump and still nothing. Had my dad break out the voltmeter and we tested the power from front to back. Well it has power up to the innertia switch but the switch itself isnt bad. We bypassed the switch by connecting a wire from the fuel pump relay to the wire on the innertia switch and soon as i turned the key the pumps started right up but the truck still wont start even though the pumps run. Is there something between the Fuel Pump relay and the innertia switch that wont allow the truck to fire up since we bypassed the system ? Only reason i ask that is cause the wire color codeing changed from the Fuel pump relay to the innertia switch so that would indicate a break in the line. And when i hit the purge on the fuel rail it spits gas out so it has pressure..just not sure if its more then enough. Also after the truck sits for a little while the pressure in the fuel line drops to nothing..is that normal also ? And to let you all know ahead of time both the low and high pressure pumps are brand new, well the high is the low is about 6 months old. We checked all the grounds and everything but is all fine except the wire that runs from the fuel pump relay to the innertia switch which seemed to be bad cause it showed a load on the voltmeter which is why we did the bypass with another wire. I just know its going to be something really stupid and easy, always seems to end up that way for me lol. I'm a little at a loss now so any and all help would be greatly appreciated.

Thanks

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 07-23-2006, 04:14 PM
Member
 
Last wiki edit: Ford axle ratio codes
Last journal entry: Rear Suspension
Last photo:
Join Date: Aug 2005
Location: Prattsville
Posts: 6,388
Wiki Edits: 31

Thanks: 2
Thanked 57 Times in 53 Posts
what is the fuel preassure reading on the rail? you need 2 things, fuel and fire, you have fire but havn't tested fuel. replace the relay just for the heck of it. it could be working but clicking off shortly after it comes on, faulty relay's can do that.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 07-24-2006, 05:54 PM
docvette's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Rebuild an alternator Last photo:
Join Date: Mar 2004
Location: Lafayette, california
Age: 62
Posts: 7,362
Wiki Edits: 12

Thanks: 0
Thanked 6 Times in 3 Posts
Doc here,

Not knowing the Engine OR Induction System, Spray Copious amounts of starter fluid into the induction system where you know it will end up in the Combustion chambers, (if need be , pull the plugs and load up the cylinders as you replace the plugs..) and try to start..

If it fires and dies, or trys to fire, Chances are it's Not the ignition..you have a fuel delivery problem, If it won't act like it has life at all..It probably spark.

FIRST check all fuses marked IGN, INJ, COMPUTER, FUEL, ECM, ECU, CRANK, be sure all (if you have them, are good.

Get an old timing lamp, hook it to the COIL wire, and crank, If it strobes, your coil secondary is good, Then Try ANY plug wire, If it strobes your fire is good to the plugs. Look at the induction/Fuel system.

Test those and post back the results.

Doc
__________________
Aftermarket Solutions
Electronic & Electrical
Innovations
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 07-25-2006, 05:37 PM
Registered User
 
Join Date: Sep 2005
Location: Michigan
Posts: 6
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Sorry forgot to mention the engine type and stuff in the first post. Its a 2.9 liter V6 with Fuel Injection. Well shortly after my first post i went and bought a new ECM relay and put it in..still nothing. I had found a wireing diagram for it on the net and it shows that there is 2 fusible links. Well i can tell you that one of them isnt there anymore cause thats what caused the pumps to not run 7 months or so ago, but not sure where the other one is. I know its probably not a good idea to run it without that link but its been that way for about 7 months now. But i tested the spark and everything and its all good. Sprayed starting fluid in it and it trys to fire up but wont continue to run. Says that when the key is turned on the pumps will run for about 2-3 seconds then shut off, well they dont do that at the moment..nothing happens actually. No pressure in the fuel rail at all. Only got pressure when i jumped the wire between the fuel pump relay and bypassed the innertia switch, but they kept on running and it wouldnt start. Hope to have this figured out soon cause its killing me not to drive it. Had it 10 years and this is really the first major thing to keep me from driving it. 216k miles and still runs great..well when it WAS running atleast..lol.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 07-25-2006, 08:35 PM
docvette's Avatar
Hotrodders.com Moderator
 
Last wiki edit: Rebuild an alternator Last photo:
Join Date: Mar 2004
Location: Lafayette, california
Age: 62
Posts: 7,362
Wiki Edits: 12

Thanks: 0
Thanked 6 Times in 3 Posts
Doc here,

If you had bypassed the fuse link , and had a short bad enough to blow it before..I'd say you hosed the pump this time...

To blow a fuse link takes a devastating malfunction Over TIME to open..not like a fuse, that just peaks and opens, but MANY amps drain.

Most likely, you destroyed the harness, or pump, or Inertia Switch, or Relay or possibly (if so configured ) the computer..

Never Bypass a Fuse link..and if you do.. you run the risk of destroying the harness and devices between. Not To mention a Great possibility of a fire erupting.

Fuse links "Just Don't blow" it takes serious trouble to kill one..

At this point, I'd try a hot wire from the battery directly to the fuel pump, (disconnect the other wire) and see if it runs..If not you need to troubleshoot the whole circuit from tail to computer.

I'm assuming that you have brand new fuel filters, and the fuel tank has a proper bonded ground.

Doc
__________________
Aftermarket Solutions
Electronic & Electrical
Innovations
Reply With Quote Quick reply to this message

Recent Electrical posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Aftermarket EFI ? x007 Engine 61 02-08-2012 10:38 AM
Power output formulas SAATR General Rodding Tech 14 05-12-2004 08:46 PM
finally time to put my indian back together bullheimer Hotrodders' Lounge 8 03-03-2004 07:23 PM
Tough questions, harder answers... 4 Jaw Chuck Hotrodders' Lounge 13 03-16-2003 07:00 AM
Alright. One more quick comp lesson 4 me HemmiGremmie Hotrodders' Lounge 13 01-02-2003 07:14 PM


All times are GMT -6. The time now is 12:12 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.