Glow controller and cold start relay - weird behavior

[Lightyear]

Finally got around to applying the glow controller relocation mod to my '88 'Burb. Starts like a champ now, but I'm puzzled. The controller cycles on its own, intermittently after engine start. Sometimes while driving along, it will just start cycling, and then stop. I noticed after replacing it with a fresh one, the my cold start relay (I think) cycles with it...crazily. If the relay is bad, will it make the controller go nuts, or is the previous owner's rat's-nest of wiring just coming to get me? BTW, thank to BobND and everyone else who helped with teh math on teh resistors.

Buzz

[BobND]

If you installed a '85 to '93 glow plug controller on the LH fender, in place of the old glow plug relay, there will not be a "cold start relay" to chatter along with the glow plug controller.

Did you get the glow plug temp override switch out of the circuit?

Also, you need a GOOD ground connection to the new controller, and also a good source of switched "ignition" 12-Volts. If you have those two things, it should not be coming on randomly after startup, assuming the new controller is good.

[BobND]

Originally posted by BobND:
If you installed a '85 to '93 glow plug controller on the LH fender, in place of the old glow plug relay, I wasn't paying enough attention... I see it's an '88, so there wouldn't have been a glow plug relay on the fender, originally.

You just moved the controller you had by extending the harness, right?

You probably do have the temperature override switch, though. With this system, and the newer (dual-coil) glow plugs, get rid of that switch.

[Lightyear]

I did relocate the controller to the left fender, extend the harness, add 2 1W 10 ohm resistors in parallel, and add ana dditional ground from the controller harness black wire to the block. Located further aft on the left fenderwell is another relay. The harness for it has 4 leads: green/black, pink/black, orange/black, and brown/black. I think. I will check again when it's daylight. Anyway, if I disconnect this relay, the controller does not cycle at all. If connected, I can feel this unknown relay cycling with the controller. Other than that, the mod was a success...glow every time, with four normal cycles, and much quicker warmup with less smoke. I'll take some photos after work tonight; maybe that will help figure out what the heck that thing is. Thanks for the help.

Buzz

[Lightyear]

Re my last: I did elimiate the thermal switch as well.

[Lightyear]

I have 3 photos from under the hood, but I'm not sure how to add them to this post. First is the relocated controller. Second is the mystery relay, and third is the connector for that relay. Will see if I can find it in the schematics tonight. BTW, no intermittent cycling on the drive to the office; will see what the trip home has in store.

Buzz

[Lightyear]

C:\Documents and Settings\rseilius\My Documents\DCAM0037.JPG

[john8662]

Lightyear,

You're going to have to find a place on the "net" to host your image, the location displayed is a local directory on your computer and not accessable to us over the net. Anyways, what you'll need is somewhere to store and host your images, so we can view them.

Here is a quick suggestion that works pretty good:

http://www.imageshack.us/

From that site you can upload your image to their server, then follow the on screen instructions and post the links back here at the forum for us to view. We'll be able to view them once they're hosted.

[Lightyear]

Thanks, John. I realized that something wasn't right as soon as I read my last post. Duh. Me use kompooter real gud. Will probably get a page like that in the next day or so. Hopefully I can find a clue in the wiring diagrams, so I can be of more help to y'all who are helping me. The resistor modification itself is working great. My truck has never started so well. It's almost scary to think what she'll be like with a couple of red-tops under the hood. Thanks again, all, will have pics soon.

Buzz

[Lightyear]

Okay, here goes. I'm trying to go through imageshack, we'll see if I get this right. Photo 1) relocated controller. (http://img246.imageshack.us/img246/6639/dcam00378cw.jpg) 2) mystery relay on left fenderwell, near hood hinge (http://img328.imageshack.us/img328/4641/dcam00382ne.jpg). 3)connector for mystery relay (http://img328.imageshack.us/img328/8938/dcam00392ld.jpg).
Hope I did this right. Anxiously awaiting comments/suggestions/laughter?etc. smile.gif

Buzz

[DmaxMaverick]

Lightyear

Your links are good, but in the incorrect format. When posting images here, use the "image" radio button below the text window, and enter the URL for the image there. Also, don't use any character before, or after, the URL if you post just a URL. It will negate the link ability.

For example, during your post, click on "image", and enter (copy/paste) the URL and click OK. Be sure to "preview" the post (click "preview post") before submitting to be sure it worked.

[Lightyear]

Computers can do that? But seriously, thanks...here goes! Again, #1 is the relocated controller. #2 is the mystery relay, and #3 is the mstery relay connector.
http://img246.imageshack.us/img246/6639/dcam00378cw.jpg
http://img328.imageshack.us/img328/4641/dcam00382ne.jpg

http://img328.imageshack.us/img328/8938/dcam00392ld.jpg

Thanks for the Help!

Buzz

[Lightyear]

Well, here's the latest. On the trip from Atlanta to Gulfport for weekend national guard duty, my glow light flickered for about 30 miles/30 minutes. Having moved the controller, it's easier to hear it cycle. That said, the light doesn't seem to indicate normal cycles, but rather looks like I'm receiving morse code. The controller sound matches the light flicker; it's definitely not just normal cycling. Is it possible I have a poor connection at the steering column ignition switch, or maybe at the starter? I added an additional ground from my new extended harness (black wire) to the ground on top of the block. My fear is this random controller activity will burn it out, and $88 a pop isn't cheap. Thoughts, anyone? Thanks,

Buzz