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Use glow plugs at every start?

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Not that it gets super cold in Texas, but simply because temperature is going down, the next week or so is supposed to be Texas cold; which is not to say it's actually cold. However all the Mexicans will be bundled up like Eskimos. :CWL: (if you're from Texas, that's less funny and more accurate).

Anyways, because of the colder weather coming, I've been reading into glow plugs. So if you don't know, the purpose of glow plugs is to heat up your cylinder before your ignition starts, to help efficiency of combustion on the initial early pumps before the engine gets up to temperature.

The general rule of thumb is the glow plug heats up to 500° in the first 2 seconds, and then up to 900° (on average) after about 15 seconds, and that's the point that you should be turning over the engine.

Now this being said, even in warm weather, it kind of makes sense to use your glow plugs at every start. However I will say that some of the articles that I was reading was saying that modern diesels regulate the glow plugs already, but if you're turning over the engine, what is it really regulating anyways. It's not like our Wranglers are sending power to the glow plugs every time we open the door and sit down.

I know we got quite a few guys on his forum with bigger diesel engines, and many of them bigger modern diesel engines.

So I ask, do you use glow plugs every time you start your engine?

Jeep Wrangler JL Use glow plugs at every start? 1000005744


As a bonus question, how long after you start your diesel engine do you typically let it idle and warm up before you start driving?

From what I've been reading, the minimum your engine should be idling before you drive is 1 to 2 minutes in 70+° weather, 3 to 5 minutes in 32° to 70° weather, and 5 to 7 minutes in any weather below 32°f.
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I thought we are getting a delayed start when we hit the button.

I understood that delay was the computer getting the glow plugs primed.
 
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I thought we are getting a delayed start when we hit the button.

I understood that delay was the computer getting the glow plugs primed.
While I do agree it is a ever so slightly delayed start, it's definitely less than 2 seconds which isn't going to get the glow plugs primed enough especially on a cold day.

I have to check the specific statistics on our glow plugs specifically, but I can't seem to find any information that says anything less than 15 seconds for a fully heated up glow plug.
 
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For anyone who doesn't know, to get the glow plugs started on our EcoDiesels Wranglers, You need to put the vehicle in run, without the engine on and you'll see that little twisted rope icon pop up on the dash which will let you know that the glow plugs are getting power.
 

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In Texas cold weather, not much changes. Because it's not actually cold.

In mildly cold weather (where Texas' power grid colapses), I do notice it takes longer from pressing start to cranking.

In seriously cold weather, it does take a bit longer still. But not more than a couple of seconds.
 
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But all of this does still make me wonder, is it not better for your engine to power the glow plugs for at least 5 seconds until the light goes off before you press the ignition?

I myself have noticed some mornings whether it's warm or not, rough starts. Comparing that to when I've been out driving for hours come home, and start the vehicle 20 minutes later with the engine still warm, it starts smooth as butter!

I wonder if those cold starts (being that the engine's not up to temperature, not that it's cold outside) are going to be bad for the engine in the long term?

I think for the next two weeks I'm going to be using the glow plugs before each start. I'll have to record a video of one of my rough starts first though.
 

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But all of this does still make me wonder, is it not better for your engine to power the glow plugs for at least 5 seconds until the light goes off before you press the ignition?

I myself have noticed some mornings whether it's warm or not, rough starts. Comparing that to when I've been out driving for hours come home, and start the vehicle 20 minutes later with the engine still warm, it starts smooth as butter!

I wonder if those cold starts (being that the engine's not up to temperature, not that it's cold outside) are going to be bad for the engine in the long term?

I think for the next two weeks I'm going to be using the glow plugs before each start. I'll have to record a video of one of my rough starts first though.
Keep in mind, this advice is coming from an engineer with OCD.

Don't overthink it.
 

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If my Jeep is outside and it gets into the 30's, I will let the glow plugs warm up. Over night, the Jeep is parked in a garage. So even on those 30 days, the garage is around mid 60's (or that's what the Jeep registers when I turn it on) I do not run the glow plugs.

@Tredsdert and I were texting this week too. Watch your Jeep battery. Mine went out on Monday. Luckily I already deleted the aux battery so jump starting the Jeep was normal. Replaced with a 850 CCA Duralast Platinum H7 (Autozone was open that night and had them in stock).
 

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If my Jeep is outside and it gets into the 30's, I will let the glow plugs warm up. Over night, the Jeep is parked in a garage. So even on those 30 days, the garage is around mid 60's (or that's what the Jeep registers when I turn it on) I do not run the glow plugs.

@Tredsdert and I were texting this week too. Watch your Jeep battery. Mine went out on Monday. Luckily I already deleted the aux battery so jump starting the Jeep was normal. Replaced with a 850 CCA Duralast Platinum H7 (Autozone was open that night and had them in stock).
Yeah we're supposed to hit 32 tonight, so when I get home from work I got to put that sock on my battery. I never did transfer it over from the last battery. :facepalm: :headbang:
 

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Yeah we're supposed to hit 32 tonight, so when I get home from work I got to put that sock on my battery. I never did transfer it over from the last battery. :facepalm: :headbang:
You're putting a sock on your battery???
 

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I just spilled my coffee when I read 30F is cold, my 2005 MB e320 CDI(Inline 6 Diesel) starts without hesitation in -10F with glow plug light going off in 2-3 seconds. Just enjoy your Jeep and dont panic until you are in single digits
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