Few glow plug issues...any ideas?

[kibs45]

I have an 82 4000 diesel N/A.  Heres how it all happened.  The car has never started real well cold.  It always seemed to try and start on 2 cylinders.  Well it ran home from work Friday night fine.  Monday morning I went to start it at about 34 degrees outside, and it just wouldn't catch. It kind of ping ping...ping ping... on and on.  Well it sat for about six hours, and I went to try again ambient air temp was about 60 degrees.  Same thing ping ping...ping ping.  Then it just kind of stopped pinging.  The battery was starting to lose its charge so I took it to a store to have it charged.  It accepted the charge, I took it home, and hooked it up.  Now the diesel light won't shut off, the relay never clicks over.  Following Vincents instructions and the Bentley instructions, and some instructions from 4crawler.com, and this is what I have.  The power terminates at the relay.  Power never reaches the engine side of the harness.  Following the guide for the electrical connections at the relay, everything looks right.  This would seem to indicate the relay failed.  My question is when the two large prongs are connected to the battery terminals it clicks, is it possible I am not getting enough amps at the relay panel, or is it just a bad relay?  Secondly I pulled the glow plugs to inspect and they were filthy coated in a oil/diesel mix.  I hooked the glow plugs up one at a time to the battery and found one worked well and quick after it burned off the filth.  Another one would light, and then dim and I would move it on the battery terminal, it would light back and dim.  One took forever to light the first time, and then lit well and consistently after.  The other one seemed ok nothing weird about it.  The only one that glowed the whole rod was the first one, all the others were about half.  Did I just get unlucky and burn it all out or once, or does it sound like my plugs might have taken the relay with them as they failed?  I plan on wiring them up like Vincent talks about, just don't know if I should bypass the relay and use push button or buy a relay and see what happens?  Thanks for any help!

[Familydiesel]

Wow, I just wrote a buch of ideas and pushed the wrong button and pooofff, no more reply!  

According to Bentleys, there are 2 glow systems:  A quick glow system which has quick glow plugs and relay; and a slow glow system with slow glow plugs and relay.  Since you have an 82, you may have the fast system.  A quick way to check is to see if you have brass nuts that bolt your glow plugs to the bus.  This is not full proof, but a possible quick way to tell.  

It may be that you may have 2 different kinds of glow plugs (quick and slow glow plugs).  Check to see if the brand and number on the glow plugs are the same.  If not, you may have a mixed set of glow plugs and/or some may be going out.  Also, you need to determine whether you have a quick or slow system and buy the appropriate plugs.  A quick glow relay has the part # 171 911 261A.  If you have had any moisture issues inside the car or live in a moist climate, I would recommend thouroughly cleaning the relay terminals both on the relay and in the fuse block.  I have worked on these cars with moisture issues, and the fuse block terminals can be a headache if they are oxidized.

Peronally, It sounds like you have a bad relay, though try to clean if first before replacing.  If you have the money, I would buy a complete set of plugs that matched and the corresponding relay.   If you don't have the money, you will still need to match the glow plugs and you could use a push button, at least temporarily, to see if the stystem works.  But if you install the quick glow plugs, make sure you don't push the button in too long or you could fry the glow plugs.  
Hope this helps.

Familydiesel

[kibs45]

Car is a quick glow system, but the relay has been previously replaced it does not have vw numbers anymore.  I do live a moist climate Portland, Or, so I guess I wouldn't shocked it that played into it.  There are not really burn marks but it looks like on the base of the relay, there might be corrosions smears near all the terminals, almost rust.  Our local german import shop as the glow plugs for $11 a pop and the relay is $28 so I guess I will get them all and go from there.

[Black Smokin' Diesel]

How good is the glow plug wiring? corrosion? Did you check the fuse? In a MK2 it's near the raintray, dunno about MK1s. Low compression can make it hard to start cold.

[kibs45]

On the audis the fusible link in on the side of the battery tray.  All the wiring seems to be fine, like I said the relay pinout testing is good.  Honestly I never had it just not start so I never checked whether the glow plugs worked or not prior to this.  I do know that before Monday the relay would audibly click in the dash and the light functioned correctly.  After the battery charge nothing.  We will see tomorrow.

[Familydiesel]

Let us know what you find out. 

[macka]

On the audis the fusible link in on the side of the battery tray.  All the wiring seems to be fine, like I said the relay pinout testing is good.  Honestly I never had it just not start so I never checked whether the glow plugs worked or not prior to this.  I do know that before Monday the relay would audibly click in the dash and the light functioned correctly.  After the battery charge nothing.  We will see tomorrow.

fusible links are known to fail and still look serviceable. check for current using a probe.

[arb]

Looks like your system fried 3 of your GP... I would replace the 3 and "pimp your glow plugs" as discussed on this forum and done by many of us. Your days of troubleshooting GP for hours will end. I added a small feature on mine that some have not - I have a red indicator light on my dash directly connected to the new pimped GP terminal so I can see if it is really getting power.

[kibs45]

The glow plugs all spec out.  I havn't written in a while because busy and half through bypassing all original GP wiring.  Going manual push butto to Pimped set up.  Put a little behind because the Ford style solenoid I originally bought was defective and had to convince them to trade me.  The relay connections all tested good and with a new relay still not luck.  Going around it all together.  Just hope it works.

Sorry forgot to mention that I was not getting power at the harness before the fusible link, so even if the link was bad I was testing in a unaffected spot before it.

[macka]

check the relay under the dash, its probably toast.

[kibs45]

That was done.

[RustyCaddy]

You probably tried this already if you are using the Bentley...but just in case.  Have you checked that the wire to terminal 86 and the fuse box is good?  If it is, Bentley suggests there could be a problem with the fusebox or the ignition switch.  My old 1980 rabbit has had problems with the wiring harness at the ignition switch which disabled the glow plug relay and the fuel cutoff solenoid intermittently...but it has the old style fuse box wiring.  Anyways the terminals at the ignition switch wiring get stretched and lose over almost 30 years and can be a pain to trouble shoot. Maybe try using electric contact cleaner then electric conducting grease on the ignition switch terminals (not dielectric grease).

There are some good links for this at VWCaddy.com if you haven't tried that already.

      

[kibs45]

My Bentley did not cover that directly, however, like I said the pin out was correct.  I have detectable voltage at the appropriate wire at the ignition switch, and again at the solenoid terminal.  This is why I decided to bypass it.  I would be much more heart broken if the car was in good shape, but its not and it gets 40 mpg so I am just trying to keep it workable.  I really appreciate all the help and we'll see how it looks on Saturday at this point!  By the way the pimped glow plug circuit is MUCH MUCH more robust.

[RustyCaddy]

It sounds like the upgraded glow plug wiring that bypasses the fusebox and runs off a manual push button switch is about as bullet proof as you can get.

Please let us know how it goes.

[janb]

... I have detectable voltage at the appropriate wire at the ignition switch, and again at the solenoid terminal.  This is why I decided to bypass it.  ... I am just trying to keep it workable.  ...By the way the pimped glow plug circuit is MUCH MUCH more robust.

Vince's pimping is a superb and ideal solution.  I do an econo version.... replace the relay with a 'high amp capacity starter push button' with short 10ga leads from the FAT relay terminals.  I have not had a problem as the high load power through the button is quite brief.  Cost ~ $3. Time ~ 10 minutes.  Can also add a relay version directly ahead of strip fuse.

BTW, I share your climate, and relays often seem to fill up with water    VW has a great way about placing water leaks directly above the fuse box  

My first diesel (78) the PO had rewired the entire fuse panel with Ford style solenoids out be battery.  It looked like and airplane job, and was dependable enough to fly