Rewiring coolant glowplugs

[bbob203]

I want to figure out a way to make them turn off when the coolant reaches a certain temp. I'm not to well versed with wiring and electronics though. My idea is to use one of these sensors in place of one of the glowplugs to feed a switch that turns off at Xdegrees. Also probably a light to show when they are on and an override switch if the temp switch doesn't turn them off.
https://www.google.com/search?q=vw+nail+head+temp+sensor&client=ubuntu&hs=40S&channel=fs&tbm=isch&imgil=PuddOqEK1vMVJM%253A%253Bhttps%253A%252F%252Fencrypted-tbn1.gstatic.com%252Fimages%253Fq%253Dtbn%253AANd9GcSMHFYltvrh0fyXXumWduKMeogzl6JOgT9ZgM_oY3YQyS4Lwaa7iA%253B640%253B480%253BqtZx2yBV6McSnM%253Bhttp%25253A%25252F%25252Fwww.cabby-info.com%25252Felectrical.htm&source=iu&usg=__at7lTvlLuMakIgo0VP3B7SGgikM%3D&sa=X&ei=5wYBU_igH6nOyQGv4oG4Ag&ved=0CCwQ9QEwAQ&biw=1215&bih=710#facrc=_&imgdii=_&imgrc=PuddOqEK1vMVJM%253A%3BqtZx2yBV6McSnM%3Bhttp%253A%252F%252Fimg.eautopartscatalog.com%252Flive%252FP403370835.JPG%3Bhttp%253A%252F%252Fwww.cabby-info.com%252Felectrical.htm%3B640%3B480

[ORCoaster]

What temp do you want to shut them down @ and why?  Once the engine is running you don't need the GP's anymore.  Just let it run and it will come up to temp just fine.  Can't you just swap the delay relay into your current system.  VW did have that on some of their models.

[libbydiesel]

ORCoater, he's talking about the glow plugs that are installed in the coolant flange at the end of the head on TDI engines with manual transmissions.  Bbob, what you are wanting to do would be easy.  Get an automotive relay rated for the current draw required by the glow plugs.  Get a temperature switch, not a sensor as you have pictured.  The difference is that a temperature sensor varies resistance across the range of temperatures.  A temperature switch is on (0 resistance or darn close to it) or off (infinite resistance) with the transition between the two at a specific temperature.  Wire the relay with the two high load connections going to battery power (with fuse) and to the glow plugs.  On the sense circuit of the relay wire switched power and then to the temp switch.  Make sure the switch has ground contact either through it's threads into aluminum or through a separate lead added.  That's really all there would be to it. 

I assume you are interested in the coolant glow plugs in order to warm your engine up more quickly.  I would mention that both of my mTDIs take a long time before they give decent passenger heat, much slower than my stock '02 Jetta.  I attribute the difference to the lack of EGR, lack of engine cover, no belly pan and reduced electrical load.  I will add a belly pan to each at some point.  A stock engine cover will not fit on either one, but I plan on making custom versions.  The coolant glow plugs would help increase the electrical load and aid warmup as well as assisting in clearing the windshield and those are also 'on the list'.  Another item 'on the list' is to get aftermarket heated seats added.  That will also help me and my passengers to be cozy while also adding to the load on the engine and assisting its warm up. 

[bbob203]

COOLANT glowplugs. So I have heat faster. The glow plugs are on the inbound coolant to the heater core so quick(er) heat.

[bbob203]

I've also been pondering some sort of pull handle to raise the idle by way of moving the throttle arm so I can bump the idle to say 1200 rpm while its idling/warming up in the drive way. When I can remember I always like to at least let my engine run a few minutes before driving for oil pressures sake.

[libbydiesel]

You should avoid extended idling prior to reaching normal operating temperature.  You certainly should not flog the engine prior to the temp needle moving but full oil pressure is achieved within a few seconds of starting the engine.  When it is very cold doing a fast idle for a max of 30 seconds or so before driving recommended, but idling longer than it takes for the oil light to go out under any other cirumstance is worse for the engine than driving gently.  A block heater is an even better way to go.

[Toby]

Ahh, am I missing something here? Aren't the coolant glow plugs controlled by the engine management computer that only turns them on when needed and off as the engine comes up to temp.

[dieseljunkie69]

^^ Not on an M-TDI..

[ORCoaster]

OK, I follow your thoughts on this one.  I was not thinking of the coolant plugs.  Duh?   As for a pull on the throttle cable to bump Idle.  Got one on mine.  It started as my cruise control.  Being of sound mind but lacking judgement I put a pull cable from NAPA on it.  I made an attachment of sorts and had the  cable clamped to the end of a beaded chain using a simple cable clamp, very small one.  I could depress the accelerator and pull out the cable till it stopped.  Then let the tension hold it in place.  Works great for that bump you talk about.  As I don't have one on the IP.

In the foreground is the Cruise control bracket that I finally found on Craigslist,  It was missing the cable that went between the controller and the throttle but I found an EBrake cable worked great.



This is a better view of both cables as they are today.  The lower beaded one is the Idle or Bump cable.

[CRSMP5]

for throttle cable bump up speed old aidi diesels have it stock on dash... just rember what ever you use can allow throttle pedal input with no binding...

my thoughts on the coolent glows...

2 relays, 1 powers 1, the other powers 2.. this way 2 buttons... 1 turns one on, one turns 2 on.. or both turn 3 on.. so you can vary how many work for alt loads... think 15a each... add in lights, heater blower rear window defrost.. 90a alt... imo too many loads to run it all.. think why tdi went 120a alts... but they lack w...

when you goto e codes with hid.. you will regain 10-15a... but the stock or normal style bulbs are 15a alone.. higher watt are even more!!

why i came up with button idea.. wanted to put on 55amp 1.6 idi dd... and learned how to max out 65a alts years ago.. just by light hid's win hands down in proper lights..

[bbob203]

i have a 120 amp alt now the eurovans have 2 terminal 120 ampers.