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Wed Nov 19, 2008 6:16 pm

I've been meaning to post about this for awhile.

First of all, thanks in large part to this forum, my old van and I successfully completed a 1200 mile trip to the mountains of north carolina! I even pushed it around on the blue ridge parkway. Yeah, the first time I went up a really serious, long grade, doing 25 mph in 2nd gear, standing on the pedal, I was terrified. But the engine didn't blow up! Anyway, a td is in my future.

But for now, I'd like some help with the one problem I did have in the mountains, which has now caught up to me in Florida--My van really doesn't like to start when it's cold outside. The temperature dropped to the low 30s at least last night. I killed the battery trying to get it to start today.

I'd like to hear any tips that other diesel drivers have. How hard should it be to start?

I pull the cold start and let the glow plug relay go through several cycles, and I push the accelerator while I hit the starter, which is necessary. When it finally does start, it sounds like hell and blows white smoke for a few seconds.

I guess I should check the compression, which I've never done. But anything else? Is it likely that the motor is just old and tired? Or that a glow plug or two isn't functioning?

I'm sure that this isn't much information to go on, but I'm open to any suggestions.

Wed Nov 19, 2008 6:47 pm

as a seasoned diesel person I can tell you that your glow plugs are not working. check the glow plug circuit to be sure it is working and then replace them. I have seen many cars sold for ultra low prices because they dont start or are extremely difficult to start. They all needed the glow plugs fixed, sometimes the glow plugs were replaced but the circuit was not functioning.

The wrong battery can also be cause for concern. But since you did not mention hard turn over it probably is not that.

any diesel should start right up with a functioning ignition system.

for reference, my diesel 1993 ford f250 with 203,000 miles started up in 07 deg like it was 90 deg with only a bit more smoke and noise. Also, my 1980 mercedes diesel statded like a dream in 22 deg, also more smoke and noise.

my current diesel vw tdi with 107000 miles startes like a new car even in 07 deg.

the glow plugs get red hot and provide a place for ignition to begin, with out it you will have a bitch of a time to get it started.

now the cummins engine is a whole different story......................

Wed Nov 19, 2008 6:52 pm

Open the engine lid. Then, turn the ignition switch on and cycle the glow plugs a couple times. Go back to the engine and touch the end of each glow plug, if any are bad they will feel cold, ones that are working will be warm. Bet you'll find at least a couple bad ones if not all. Also, check the flat fuse on the little black box on the firewall. Report back with what ya find.

Wed Nov 19, 2008 7:06 pm

At seal level and 30* the van should start up reasonably without waiting for the glow plugs at all.

Check the injection timing, %90 of IDI hard start issues I fix are bad injection timing.

Altitude makes far more difference than temperature when it comes to how long the glow plug light stays on, (with a TDI that is) at sea level and 25* F out my GP light stays on for about a second, while at 6200' and 80* out my GP light stays on for ~5 seconds, as you're at sea level the glow plugs are fairly irrelevant in all but the coldest conditions, well below freezing.

If your plugs are bad and you replace them it will help your hard starting, but the GPs are not the root cause of your hard starting. I'd start with injection timing.

How many miles are on the engine?

Wed Nov 19, 2008 7:20 pm

if it were timing it would be hard to start in warm weather as well.....

Wed Nov 19, 2008 7:27 pm

wgargan wrote: if it were timing it would be hard to start in warm weather as well.....

Not so, in my experience. They'll start ok when its warm, but when its cold the timing becomes enough of an issue that the car won't start.

I've had cars come to me that would hardly start at 70*, but would start just fine when warmed up because the hotter the engine the easier it will start. Once I adjusted the timing it started quite happily at 30*.

Wed Nov 19, 2008 7:28 pm

Thanks for the fast replies!

Quote: Open the engine lid. Then, turn the ignition switch on and cycle the glow plugs a couple times. Go back to the engine and touch the end of each glow plug, if any are bad they will feel cold, ones that are working will be warm. Bet you'll find at least a couple bad ones if not all. Also, check the flat fuse on the little black box on the firewall. Report back with what ya find.

The engine is warm right now, so I'll need to wait until later tonight or tomorrow to try this. I'll post again when i do.

Quote: How many miles are on the engine?

I really don't know. The van has 83000 miles on the odometer, but it wasn't working for a few years (while the PO had it). I was told that the engine was replaced at some point, but I have no idea if that's true, or where the replacement engine came from.

The timing sounds just slightly off when it's cold, unless I pull the cold start cable. It's sounds fine when it's warm. I'm sure this isn't sufficiently accurate!

It does start with no trouble at all when the weather is warm, or when it hasn't had time to cool down completely.

The glow plugs are doing *something* at least, because I can see a voltage drop when the relay is on, and the engine starts more a little more easily when the engine is cold (but the weather is mild) if I let the relay cycle.

Wed Nov 19, 2008 7:29 pm

jackbombay wrote: wgargan wrote: if it were timing it would be hard to start in warm weather as well.....

Not so, in my experience. They'll start ok when its warm, but when its cold the timing becomes enough of an issue that the car won't start.

I've had cars come to me that would hardly start at 70*, but would start just fine when warmed up because the hotter the engine the easier it will start. Once I adjusted the timing it started quite happily at 30*.

I guess I'd better check the timing.

Wed Nov 19, 2008 7:36 pm

jackbombay wrote: wgargan wrote: if it were timing it would be hard to start in warm weather as well.....

Not so, in my experience.

most likely your experience is more than mine....So i trust what you say more than my own

However, the starting will not be as it should if the timing is off (right?). However, it is hard tell any difference if you don't know any better.

Wed Nov 19, 2008 8:04 pm

wgargan wrote:
However, the starting will not be as it should if the timing is off (right?). However, it is hard tell any difference if you don't know any better.

If the timing is off a bit it will have a small impact on the starting in warm weather, a bit more smoke if the timing is retarded, some more noise and rougher running if the timing is advanced, but all in all the car will run "fine" once up to operating temp.

Thu Nov 20, 2008 6:40 pm

The wrong thickness head gasket will also cause the diesel to not start very well (using a 3 notch when it needs a 1 or a 2).

Thu Nov 20, 2008 6:54 pm

Ok, well this morning it started without too much of an ordeal, probably in part because I cycled the GP relay many times while I was feeling around to check each plug for warmth.

It's a little hard for me to tell, but I think it's very possible that at least a few aren't working. They all have 12v, and the thing on the injector pump definitely gets warm. Some of the plugs don't seem so warm.

I'll try to check it this weekend. I don't know anything about adjusting the timing, so I'll look into that too.

I'd like to get a 1.6td before I take another long trip, so if this motor has low compression (or the wrong thickness head gasket), i'm not going to worry too much. It does consume a significant amount of oil, more now than before my trip, i think.[url][/url]

Thu Nov 20, 2008 7:26 pm

replace the plugs. if you have not done it, my guess the previous owner never did it, its time to do it. I would put a dollar on it that it will cure your cold start problems.

powering up the hills, thats a different story.

Thu Nov 20, 2008 8:11 pm

If everything is correct with your 1.6 diesel, then it should fire up on the first rotation of the engine down to the teens° Fahrenheit.

One very good maintenance routine I do is to remove the injectors (taking care to only push toward the head so that the bosses that the injectors screw into don't get cracked), cycle the ignition on and look down into the injector holes. If the glow plugs are working, you will visually see all four glow brightly. While the injectors are out I do a compression check and pop test the injectors. Replace the heat shields and any non-functioning glow plugs or injectors as necessary. Correct timing makes a BIG difference in cold starting (thus the cold start advance :wink: ), as does cranking speed. I have found that even engines with very poor compression will start right up if the glow plugs, timing and cranking speed are right up to par.

Andrew

Thu Nov 20, 2008 9:45 pm

Andrew A. Libby wrote: If everything is correct with your 1.6 diesel, then it should fire up on the first rotation of the engine down to the teens° Fahrenheit.

Correct timing makes a BIG difference in cold starting (thus the cold start advance :wink: )

There is a second vote for "the glow plugs are not the primary problem you are dealing with, your timing should be checked".

As you are consuming a "significant amount of oil" there is a decent chance that the compression is low which will cause hard starting even if everything else is spot on.

Thu Nov 20, 2008 10:02 pm

jackbombay wrote: Andrew A. Libby wrote: If everything is correct with your 1.6 diesel, then it should fire up on the first rotation of the engine down to the teens° Fahrenheit.

Correct timing makes a BIG difference in cold starting (thus the cold start advance :wink: )

There is a second vote for "the glow plugs are not the primary problem you are dealing with, your timing should be checked".

As you are consuming a "significant amount of oil" there is a decent chance that the compression is low which will cause hard starting even if everything else is spot on.

I think the opinions are coming into play..... As long as the glow plugs become red hot you will have ignition. If the compression was low you would have poor starts even in the warm weather. The easiest and fastest solution is to replace the glow plugs and see what happens. If it does not help you can then check the timing and you will know that you have new glow plugs ( which you probably needed anyway). Getting the timing on a diesel is not as easy as hooking up a timing light. You need some specialized equipment to have ACCURATE measurements, sure you can drip time it but that is not as accurate as it needs to be.

Thu Nov 20, 2008 10:44 pm

wgargan wrote: If the compression was low you would have poor starts even in the warm weather.

That is not what I have experienced. Timing and compression can be fairly poor and the engine will start decently in warm/hot weather, but when the temp drops notably the engine cranks slower due to thicker oil and less giddy-up from the battery, the slower the engine turns the lower the resulting temperature of the compressed air in the cylinder, low compression thrown in on top of that as well reducing compressed air temp even further is often the "straw that broke the camels back" ie car won't start.

wgargan wrote: The easiest and fastest solution is to replace the glow plugs and see what happens.

I can check the timing in less time than I could change 4 glowplugs, its easy, and free. If he doesn't have a dial gauge to check the timing he needs to buy one anyway as he plans on swapping a TD into the van someday, a dial gauge is ~$50. here is one with the cam locking plate and the pump locking pin for $75.

Thu Nov 20, 2008 10:56 pm

I actually had a 1.6 Jetta that had 300,000 miles on the motor and compression of 400, 320, 320 and 230 for compression and it would start right up at 7,000 ft in elevation down to the teens without use of a block heater. Below 15°F it would want the block heater. It NEVER had any hard starts above 25°, EVER.

Cranking speed, timing and functional glow plugs are more important than compression, as long as it's not zero.

I've never heard of "drip timing" a VW diesel. Mercedes, sure, but haven't heard of doing that with a VE pump.

Andrew

Fri Nov 21, 2008 7:32 am

I seem to recall testing glow plugs installed in the block to be an easy procedure using a simple ohm meter. Just pull the wire and test the resistance of the glow plug connector to ground. A failed glow plug will show far more resistance than a good one - kind of like testing an electric water heater element. Test all the plugs, and compare the results. No need to remove them unless they test bad.

I don't own a diesel VW, but this method worked to test glow plugs on compact tractor engines. I dealt with quite a few in my previous career.

Go ahead and flame me if I'm wrong. I'm used to it!

Fri Nov 21, 2008 7:48 am

Don't forget that you will need a lighter oil in cold weather. As things get colder the oil turns to molasses causing the cold engine to have to work harder to start. What grade oil are you using now?