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Discussion Starter #1
It's been getting in the 40's over night which is cold here in phoenix. When I start it up it starts fine but a minute or not even a minute after- it will start to idle absolutely crazy. Random knocks and the whole car is practically bouncing because of it. Of course, after a few minutes of warming up it is fine and purrs- should I be worried about damage? What is a solution to this? I do not have easy access to plug in the block heater.
 

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Mine runs like crap when I first start it up on cold days (below around 40degs). It clears up after just a few seconds of idling. It clears up quicker if I give the accelerator a push or two after starting. I thought this was normal, but maybe I should also look into my glow plugs?
 

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If your glow plug light comes on when you turn the key to the "ON" position and stays on for a few seconds while the glow plugs cycle, you don't have anything wrong with them. If the light does not come on, you probably have a bad glow plug or maybe more than one. The realy could also be suspect if the light does not come on. It is located on the left front fender in the engine compartment. I live in Ohio and on cold mornings (between 0 and +32 degress F) my 300D sounds like it is going to rattle apart for the first minute or so that it is running. Diesel engines don't like to be very cold, and they will protest about it. They need heat for proper combustion. Nothing to worry about, just let it warm for a minute or two before you drive it, and you will be fine.
 

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Discussion Starter #5
Having a bit more worry, to respond about the glow plug light, the light does indeed come on and stay on for a while.

Anyway the temp has risen a bit and I have found even when 60 F in the morning I am still getting these "hiccups" and by hiccup I mean it is visually shaking the car jolts.

In general the car seems to be just louder.

Right when I start it is runs smooth and higher idle- and rather quiet for the first 30 seconds. If I do not start driving then the car starts hiccuping and shaking. If I do start driving it will still hiccup as I accelerate and it probably looks like im pulsating the gas pedal.

Do I need new glow plugs? Relay? Might have a shop take a look.
 

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KASarich is not correct in his statement that if the light works the glow plugs are all fine and working properly.

Flyinghigh, do you get smoke at all when it starts when cold? (light gray color? Does it start easy when engine is warm?
If yes to either question, you DO have a glow plug or glow plug relay issue.

My glow plug light worked perfectly fine but I was having a brutal time with cold starts. Once it started it smoked like a locomotive for a 30 seconds.
I knew my GP relay was fine, I just replaced it in it fall.

I checked each glow plug with a voltmeter and 3 of my 6 glow plugs were bad. I replaced all 6 of them and now the car starts perfectly with no smoke (unburned fuel) at all. After I changed the glow plugs I left the car sit outside overnite (usually in the garage) It got down to 19 degrees, in the morning I got in, ran the glow cycle and it fired right up with no stumbling at all.

Search for threads by me and there is a link there that gives you a step by step how to check each glow plug and the relay.
Dont pay a shop to do this, follow the directions in the link and you will have it done yourself in 10 minutes and know EXACTLY what is wrong.
If you dont own a digital multimeter, you can buy a cheap one at Sears for $20.


good luck

Mark
 

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Discussion Starter #7
Yes I took a look at the link you were talking about and I will give it a go. I am having smoke as I drive along cold.

When I start it is starts right up and idles high for a few seconds, then it sounds like it's breaking apart and starts thumping the car around.

Warm starts are fine

I'll be getting a multimeter and testing out the relay but I won't be able to get the plugs until I am home from school and have a garage of tools.

It's getting warmer here in phoenix so I'm hoping it won't be too much of an issue until it got cold again.
 

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I have the same problem with my 92 300d. No matter how cold, it starts and runs completely smooth. Then after about 30 seconds to a minute, it starts coughing and smoking. Once it warms up, it's totally fine. Even hot starts are not a problem. I replaced my glow plugs and still the same issue.

Just wanted to follow up on this since I didn't see if you solved it.
 
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