Hard Starting

I have a 03 Jetta TDI. The battery voltage is 12.61 V. I use synthetic oil and last week the fuel oil filter was changed. The glow plugs are relatively new with about 10,000 miles on them. My problem is this. After setting overnite with the temperatures hovering around 30 degrees F., it will take about 10 seconds or so to start the engine. Obviously, there is a lot of smoke due to the injectors putting fuel into the cylinders. This occurs every morning. Now, with usage during the day and also with a cold engine, the engine starts up immediately with no problems and no smoke. I have used Seafoam to clean the injectors as well as to rid the engine of carbon. Could the problem be the glow plug relay? If not, what should I be looking at? Any help would be greatly appreciated due to living about 100 miles from the dealer.

Reply to
wja
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Replace your battery. It should be reading 13.2 volts when fully charged.

Reply to
Erik Dillenkofer

Naw, 12.6 volts is OK...

Check to make sure the glow plugs have voltage when they are cycled on... Use either a meter or a test light. If it has a block heater, try plugging that in, and see if that makes a difference.

Reply to
PeterD

Well the battery is getting marginal, may be time to replace it. Also you might have ended up with some air in the fuel system with that filter change.

Reply to
Joseph Meehan

Brand new battery in my 03 tdi. It reads 12.6 v overnight but it did not get that cold last night. I had replaced it because the starting motor was spinning a bit slow when we had a cold snap of 30F days.

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I filled up my tank Wednesday. I did not notice the usual foaming when topping off. The supplier is supposed to be selling cold weather B50 which is foamy when topping off. B100 has barely any foam. Friday morning with overnight temps outside close to freezing (car in garage) the car took at least 10 seconds to start which is very unusual. That kind of start time is typical after a fuel filter change. The car ran a bit odd that day. I added 2.5 gallons of pure dinodiesel and drained a little fuel out of the filter. I saw no water. Car was still running off and skipping a bit. I attached the Vagcom and tried some testing. Full throttle in third and fourth was horrid after about 2500. I got home and discovered I should have been reading group 3 for the MAF test. I tried that test again heading out to get dinner. The car ran fine with no performance lags in higher rpms. Just the typical unimpressive diesel performance. The log shows that MAF is working ok. I guess my car got in a limp mode somehow that was reset when I turned the car off.

I tried to start it this morning and it started right away. Maybe it liked the warmer weather. I have found out the hard way that some B100 will gel somewhere around 40. It may be that Friday morning was a bit too cold for the mislabeled fuel. The winter blend someone screwed up on.

When I start the car in the rare really cold weather without doing the glow plug thing first I notice that the idle is lumpy until the car starts running properly on all 4 cylinders. Since it does not get cold very often where I live I am used to just turning the key just like my gas vehicles.

If you want a lot of diesel geeks to answer your questions you need to head over to

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Not too many diesel owners in this group. Their FAQ may have some answers. I know they have some testing procedures for glow plugs over there.

You are turn> Well the battery is getting marginal, may be time to replace it. Also

Reply to
Jim Behning

If you let your battery sit overnight (car not running and not hooked to a charger), it will not ever read 13.2 volts. 12.61 volts is very good.

Reply to
Tom's VR6

LOL! Attack of the bad battery cloners!!!! My father has a 2000 TDI with the original battery still in it. It starts right away with only 26K miles on it. I would imagine that due to the low mileage the battery would last a bit longer. Still everyone here seems to be using age as a battery gauge.

It sounds to me like the injection pump could be off timing a bit. I don't think the injectors are bad at only 100K miles. Time to check the injection pump timing. If applicable.

Reply to
Peter Parker

I would also add checking the water separator if you have never done that during the 100K miles. EGR cleaning too? You should try to get your TDI scanned with a VAG-COM.

Reply to
Peter Parker

Thanks to each and all for your responses. You have given me new possibilities as to what is wrong. The VagCom thought is the way that I'll have to go. To analize the situation, rather than parts substitution, is the way to go under these circumstances. It will be more fruitful and much less expensive. When I find what the problem is, I'll let the group know. Once again, thank you.

Reply to
wja

in your dreams! Fully charged battery is 12.6v.

Reply to
Lost In Space/Woodchuck
1- check the EGR and shutter valve for sticking and crud. 2- get the battery load tested. 3- pump timing- advance it to the upper limit of the spec window.
Reply to
Lost In Space/Woodchuck

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