Author |
Message |
iceracer Samba Member
Joined: February 28, 2006 Posts: 949 Location: Milwaukee, Wisconsin
|
Posted: Sat Mar 10, 2007 7:03 pm Post subject: 87 vanagon - no spark |
|
|
So a friends 87gl wouldn't start today. Was driving it and stopped and wouldn't crank. He crawled under it and shorted out the starter and then it cranked but no start. I looked at it and fuel pump not running. Hooked up jumer wires to pump and pump runs but no start. Now no spark at coil. Coil has power but no spark when cranking. Also fuel pump not running when cranking or turning on key. All fuses ok. The fuel pump relay and other (silver box) relay located in black box above the coil both click when key turned on and off. Any ideas out there???? |
|
Back to top |
|
|
Terry Kay Banned
Joined: June 22, 2003 Posts: 13331
|
Posted: Sat Mar 10, 2007 7:21 pm Post subject: |
|
|
First see if you have power coming out of the ignition switch.
This would be the firat place to start.
If you have juice to the coil, but not the starter, chase back the wiring from the starter to the battery & ingnition switch.
if you have juice to the in side of the coil, but not out, suspect a bad coil.
It's just a process of elimination--and a pain but if youhave an ice pick circuit tester, or a digital multi meter you'll trace it down in no time. _________________ T.K. |
|
Back to top |
|
|
iceracer Samba Member
Joined: February 28, 2006 Posts: 949 Location: Milwaukee, Wisconsin
|
Posted: Sat Mar 10, 2007 7:35 pm Post subject: |
|
|
I already checked the ignition switch. Power there and at the coil but no spark. Coil also has power when cranking. Also no fuel pump running, but fuel pump runs if you hot wire it. All grounds are connected but of course rusty. |
|
Back to top |
|
|
Terry Kay Banned
Joined: June 22, 2003 Posts: 13331
|
Posted: Sat Mar 10, 2007 7:51 pm Post subject: |
|
|
No spark at the air gapped coil wire, or at the spark plugs?
Fuel pump relay connections corroded,relay working intermittantly, or fuel pump power supply ground wire corroded.
If you got 12 volt juice into the coil but none out--no zap with an air gap to the block, suspect the coil. _________________ T.K. |
|
Back to top |
|
|
tencentlife Samba Member
Joined: May 02, 2006 Posts: 10067 Location: Abiquiu, NM, USA
|
Posted: Sun Mar 11, 2007 4:28 pm Post subject: |
|
|
None of the circuits involved here are fuse-protected, by the way, so it's a good idea to remove the battery ground when working on connections.
Always first make sure you have good battery connections and voltage, and good groundstrap connection on any no-start problem.
Then make sure the solenoid trigger wire #50 goes hot when you key to crank.
Not hot? New ignition switch.
Check that the starter + pole connection is clean and tight (unground battery when doing this!). Check the starter mounting bolts are tight. Check the tranny groundstrap.
All good? Still doesn't crank? New starter.
If it cranks now but still doesn't run, just turn the key to run position, and listen for the fuel pump to run. It should run for 1.5 seconds each time you key on. That verifies that the positive current path that supplies the ECU and fuel pump is intact, including both relays.
If it does, check out the other wire connected a the #50 pins on the solenoid. Make sure it's a good connection. This gives the ECU the signal that the motor is being started. You can jumper power to the coil and fuel pump, but without this signal the ECU won't signal the ign coil and injectors while cranking.
If the fuel pump doesn't run briefly with a key-on, check the + pole connections at the starter and alternator are good. This is the + current path to the ECU relay.
If those connections are good, remove the left-side relay in the box. Jump the two pins that make a "T" to each other , #30 and 87. That manually powers the ECU. If you can start it now, that relay is bad (I know, you heard it clicking; that means it's getting a signal, but doesn't guarantee that the contactor is closed).
If that doesn't make it run, remove and jump the other relayas well, the same way. That is the fuel pump relay.
Try those things and let us know what happens. |
|
Back to top |
|
|
iceracer Samba Member
Joined: February 28, 2006 Posts: 949 Location: Milwaukee, Wisconsin
|
Posted: Fri Mar 16, 2007 2:03 pm Post subject: |
|
|
So this is embarassing. So i was checking all the wiring out etc trying to figure out why no spark and I checked the black box on the firewall where you always have 12v power and guess what , no power. So I look at the alternator and no power there coming from the starter. So I stick my hand back by the starter adn lo and behold I am holding a broken off wire in my hand.
So theres the problem, Alternator wire broke off at starter and shut down all power to the computer which shut down the spark. Learned something new and only took me about 3 hours of checking and reading. Should have looked there sooner. Moral of the story: Never assume the worst like I always seem to do. It is always something much simpler. |
|
Back to top |
|
|
erobey Samba Member
Joined: July 30, 2009 Posts: 7 Location: American Nomad
|
Posted: Thu Jul 15, 2010 10:50 am Post subject: |
|
|
tencentlife wrote: |
Then make sure the solenoid trigger wire #50 goes hot when you key to crank. |
How do I know if the above trigger is hot or not? I am having a no-crank issue, have a two-year old starter so i don't think it is that, but could the solenoid be bad itself and the ignition switch is OK? when key is turned, lights and bells sound, can hear the fuel [ump whirring, but nothing else. i already have a hot start relay and replaced the fuse on it. nothing.
checking prices fr new ignition switch and solenoid too. any help is greatly appreciated. |
|
Back to top |
|
|
tencentlife Samba Member
Joined: May 02, 2006 Posts: 10067 Location: Abiquiu, NM, USA
|
Posted: Thu Jul 15, 2010 11:06 am Post subject: |
|
|
A 12V testlight and/or a VOM should be in your tool kit. _________________ Shop for unique Vanagon accessories at the Vanistan shop:
https://intrepidoverland.com/vanistan/
Please don't PM here, I will not reply.
Experience is kryptonite to doctrine. |
|
Back to top |
|
|
RicoS Samba Member
Joined: December 02, 2006 Posts: 583
|
Posted: Thu Jul 15, 2010 7:38 pm Post subject: |
|
|
tencentlife wrote: |
A 12V testlight and/or a VOM should be in your tool kit. |
. . . and, with 25-year-old Vanagon wiring, the Grace of God.
The real problem is that all the old wiring, terminals and components in any Vanagon, often create intermittent symptoms which can lead you down a trouble-shooters road to Hell. Also, unloaded circuits will often test good whenever they are not.
Sunday, I worked on a no-spark Syncro. I methodically went from the coil to the Hall sender to eventually the ECU. I didn't want to accept the idea that the ECU had shit the bed mostly because they seem so robust and also because they are so expensive. But, the twisted path lead there, so I popped in my backup ECU.
It fired right up - three, four times. When I finished buttoning up everything and was basking in the self-satisfaction of wrestling another pig to the ground, I told Johnnie Cash, Jr. to move the van. The whore would not start!
I went through the routine I had just followed and it now appears that the ECU power relay is hinky, although it had tested good an hour earlier.
So, a relay is on its way and I have to wonder where that will lead me.
Richie |
|
Back to top |
|
|
morymob Samba Member
Joined: November 09, 2007 Posts: 4683 Location: east-tn
|
Posted: Fri Jul 16, 2010 3:50 am Post subject: |
|
|
Since u shorted across starter and it turned engine, seem normal?? Do u have a tac, if when cranking over does it move a bit as engine turns, if not probably no sig from hall sensor. Or while cranking remove plug wire (1st) and hold close to gnd and check for spark. |
|
Back to top |
|
|
|