Hard starting when cold, for the 10,000th time!

How cold is too cold?

I have always been extremely impressed with how well my A3 starts in Canadian winters - the glow plug light takes a little longer to go out, but it always starts when the first or second cylinder goes over compression and the idle smooths out after a few seconds.

Mind you, I rarely go north of the 45th and until last week, I don't recall asking an A3 to start at much below -20C (-4F).

I headed further north than usual last week and twice needed to start the TDI when it was -35C (-31F) out. On both occasions the glowplug light took an eternity - not timed, but it had to be at least 45 seconds. The engine fired immediately as usual, but quit after a few revolutions. It took 7-8 attempts to get it running - each time the glow plugs took a few seconds less, and the engine managed a few more shaky revolutions before quitting. Once it ran, the amount of clanking and shaking was quite disturbing until the idle finally smoothed out after a couple of minutes.

Two questions:

• Is the starting but quitting behavior normal at these temperatures, or do I have a problem?
• Did I use the correct procedure, i.e. shut off the ignition for a few seconds, back on and wait for the glow plug light, try starter again?

Maybe next time try "chasing" the starter... hold the key to start for a couple seconds after the first signs of combustion. Also, maybe try the "double glow"... wait for the light to go out, turn key off, back on, wait for it to go out again, *before* cranking.

I think if you're getting any signs of life at all at those temps, you're in good shape.

Hi,
I have a problem with a 2001 TDI 100Pd A3. My first thought was the Glow plugs so I changed them, no difference. Then I found this forum, Very impressed but still a bit stuck. The glow plugs are OK the temp guage seems to be OK. The car has only done 38,000 miles, so what should I ckeck next. In other words is there an order of most likely things which could be wrong?
Thanks
Wallace

Hahahah nice sig line.

More than likely the problem is retarded injection timing. It must be set to the advanced side of the allowed spec for good cold starts on non-PD cars, but I'm not sure how/if it can be adjusted on PD models.

Other possibilities are dirty injectors, clogged intake, weak battery or starter (but none of those are likely with 38k miles, well maybe the battery... sounds like it's done a lot of sitting around).

How/when did the problem come about?

It just started since the weather got cold and it is not too bad inless it's below zero. I have been heating it twice and that seems to help.

so you didn't have the car last winter?

You might try starting a new thread in the PD section... this one is getting a bit long in the tooth and the people who are knowlegeable about PD might be missing it.

No we did have the car last winter and it was fine then. I will do another thread in the pd section though, will call it Cold starting problems, how's that for originality.
Cheers
Wallace

00 jetta hard start (cleaned EGR new starter...)

My girlfriends 2000 Jetta TDI starts hard in the cold. The first start will take about 6-8 seconds of cranking to kick over and idle is 100% perfect right after hard starting. Here is some other info...


1. new starter (non-bosch)
2.battery is good (vw checked)
3.4 new glowplugs (bosch)
4.injection timing was checked, vw said upper middle and told me it was pointless to change.
5. cycling the glowplugs has an small effect, but does not solve the problem
6. even on the coldest day, once it starts you and turned off quickly ( 5 seconds of running) it will fire back up instantly (like summertime) no problems.
7.I have cleaned the EGR valve and the intake is about 70% open.

what to do next? any ideas

Last resort, do the Wingnut glow adaptation.

timmyd said:

My girlfriends 2000 Jetta TDI starts hard in the cold. The first start will take about 6-8 seconds of cranking to kick over and idle is 100% perfect right after hard starting. Here is some other info...


1. new starter (non-bosch)
2.battery is good (vw checked)
3.4 new glowplugs (bosch)
4.injection timing was checked, vw said upper middle and told me it was pointless to change.
5. cycling the glowplugs has an small effect, but does not solve the problem
6. even on the coldest day, once it starts you and turned off quickly ( 5 seconds of running) it will fire back up instantly (like summertime) no problems.
7.I have cleaned the EGR valve and the intake is about 70% open.

what to do next? any ideas

Click to expand...

same problem with my jetta since i got it with ~30k on the clock. did pretty much all you did plus i even replaced the glowplug harness.

bottom line, i put in a zerostart heater, and now it starts like summer. there is definatly somting up. but damn if i can find it.

it almost acts like the computer is not setting the timing right when cold.
my other thought along those lines is if a temerature sensor someplace was out of wack. in my case the glowplug on time seems fine when its cold. but maybe the temerature sensor that effects timing is diffrent then the one that effects glowplug on time. maybe somone knows that here.

i do the cycle trick when it i forget to plug the car in at night, or when i go home from work. it does help,even if its just a little.

you might check into a new glowplug harness, the are classic for going bad.

ZapBuzz said:

same problem with my jetta since i got it with ~30k on the clock. did pretty much all you did plus i even replaced the glowplug harness.

bottom line, i put in a zerostart heater, and now it starts like summer. there is definatly somting up. but damn if i can find it.

it almost acts like the computer is not setting the timing right when cold.
my other thought along those lines is if a temerature sensor someplace was out of wack. in my case the glowplug on time seems fine when its cold. but maybe the temerature sensor that effects timing is diffrent then the one that effects glowplug on time. maybe somone knows that here.

i do the cycle trick when it i forget to plug the car in at night, or when i go home from work. it does help,even if its just a little.

you might check into a new glowplug harness, the are classic for going bad.

Click to expand...

would I not get a check engine light if the harness was bad? I got a check engine light when the glowplugs where bad, changed all 4 and the check engine light went out as soon as I started the car.

there should be a code if the harness is intermitent or bad.

oh somtning i noticed with the zero heater. and may go along with my temerature sensor theory.

i get no nada 0 smoke when i start it. and without it i do, even in the summer.

by temperture sensor do you mean coolent temperature or fuel temperature (I think there is one in the fuel injector....) sensor

Well, not knowing what temperature sensor effects what in the ECM programming is my downfall, so...i dont know...
I'm hoping someone esle knows.
but in short we do know that teperature effects things such as injector timing... could be fuel, air, coolent or a combination of them .... still just a theory on my part. i guess i could do some voltage checks when it is cold.

Hi,
I'm new to the forum I have been reading the posts I have an Audi A3 1.9TDi I changed the glow plugs and the engin cooling sensor but I still have problems starting it up in the morming, once its running it will start with no problem what
Can anyone give me advice on what to do next? I dont know when the cam belt was last changed

many thanks

gix

try a couple of the other things that usually go hand in hand with cold starts like gp, gp harness, timming, battery strength, the fuel, but that depends on if its cold enough where you are for it to gel. im still trying to figure out my problem to, but im only left with one thing is left and of course its the most expensive one....

starting problems cold and not so cold

My turn-2 weeks ago my my 98 Jetta tdi was hard to start-cranking fine but it was a struggle to start. When it did it was blowing black smoke and the check engine light didn't go off. It had been as low as 12 degrees but it was in the 20's that morning. No trouble till then and my glow plugs were only about 21/2 years old, the harness was replaced last year.

Brought it to the dealer for a diagnostic- glow plugs and relay. Brought it in a few days later (same starting behavior even 'tho it was warming up outside) they did the work-next morning same thing. I brought it back-they said it has a sporatic fault and needed the harness replaced. Because it was sporatic they didn't do it before. I waited while the replaced the harness-(I paid for the $50 part, they ate the labor) it was warm so it started easily. The next morning hard start, black smoke, CE light.

Brought it back-the mechanic came out to talk to me. He checked the plugs, the relay, the harness-all good. I told him that when I started it I tried A-just cranking it till it started and B-cranking it a few times, then turning it off and cranking it a few more until it started. It was the same both ways. They kept it and gave me a new Jetta loaner. I have to add here that these guys were nice, took responsibility and were respectful-they "had" to ask questions that implied I'm dumb to rule things out, but apologized for it. I didn't have to ask for a loaner-they offered and they have called and updated me every day. The dealer I bought this car from lied to me and lied to me about almost everything even though I gave them tens of thousands of dollars for the cars I bought and the years I had service done there.

They had another tech look at it-he replaced the "maxi fuse" and it seemed to be fine. I went in the next day-it didn't start as easily as it should have with new plugs, etc., it blew smoke. I turned it off and tried again and again-better each time. By now it's in the upper 30's-40's so it's not cold-car was sitting in the sun and it was about 1PM.

I pulled out onto the road-the CE light came on. I pulled over, turned it off, started again-it was fine. Pulled out - CE light came on.

Brought it back, they handed me the keys to the loaner and that is where it stands. Driving a new Jetta has been fun (and I now know I wouldn't want to buy one) but I want my car back. I know this is long but I tried to tell you everything and I would appreciate any imput you can offer. I intend to print this thread out and bring it to them.
TIA-
Dorothy

You mention the CE light several times, but you don't say what code(s) were being set. That would be very helpful information.

Black smoke is too much fuel for the air supply... implies retarded timing and/or bad fuel injectors(bad spray pattern), or restricted intake. You haven't mentioned the timing, that should be the first stop on the troubleshooting flowchart after glow plugs.

Did this come about suddenly or gradually get worse?

gix said:

Hi,
I'm new to the forum I have been reading the posts I have an Audi A3 1.9TDi I changed the glow plugs and the engin cooling sensor but I still have problems starting it up in the morming, once its running it will start with no problem what
Can anyone give me advice on what to do next? I dont know when the cam belt was last changed

Click to expand...

Gix- "I don't know when the cam belt was last changed"... that's BAD news. Change it ASAP - a broken cam belt equals a seriously damaged engine on these cars.

Make sure the injection timing is set to the *advanced* side of the range for easy cold starts.

tadc said:

You mention the CE light several times, but you don't say what code(s) were being set. That would be very helpful information.

Black smoke is too much fuel for the air supply... implies retarded timing and/or bad fuel injectors(bad spray pattern), or restricted intake. You haven't mentioned the timing, that should be the first stop on the troubleshooting flowchart after glow plugs.

Did this come about suddenly or gradually get worse?

Click to expand...

It happened suddenly. 10:30 PM no problem, 8AM problem. The smoke lessened once the engine began to run.

Ahh-codes, they didn't tell me anything except that the first time it indicated bad glow plugs and relay, then the sporatic fault that they traced to the harness. What should I ask them that will narrow it down? The CE light stayed on each time until I picked it up Sat. That time it went out when the car started, but came back on within a minute of driving.

Sounds like the same glowplug code each time(there's not a different code for "bad glow plug" vs "bad relay" vs "bad harness", that's up to the tech to troubleshoot)... however in my experience the borderline issues with the harness will turn on the light long before they will cause a starting problem.

Bottom line... if it's throwing a glow plug code, there's still something wrong with the GP circuit. If it's not the relay, and it's not the plugs, it must be the harness. The smoking problem is *probably* related to whatever is turning on the CEL light, assuming that the CEL is a GP code and not something else.

tadc said:

Sounds like the same glowplug code each time(there's not a different code for "bad glow plug" vs "bad relay" vs "bad harness", that's up to the tech to troubleshoot)... however in my experience the borderline issues with the harness will turn on the light long before they will cause a starting problem.

Bottom line... if it's throwing a glow plug code, there's still something wrong with the GP circuit. If it's not the relay, and it's not the plugs, it must be the harness. The smoking problem is *probably* related to whatever is turning on the CEL light, assuming that the CEL is a GP code and not something else.

Click to expand...

Well-Dave at Langan just called and told me a third tech looked at it because the "maxi fuse" they replaced is blown again. He said on Friday he started and drove it several times and it was fine. That was not the case for me Sat when I picked it up.

He told me that along with everything they replaced there is another bigger relay-very much like a computer-and that is blown. The cost is $100. for the part, which he has to order-the labor will, once again be free. I agreed-there really isn't a choice in the matter. It will be done Wed but he wants to keep it another day or two to be sure. I miss my car.

At this juncture I can't help but wonder if it -really- needed the plugs, harness, fuse and relay that have all been replaced in this not at all cheap venture but, again, there isn't much I can do.

Because of ongoing flywheel/clutch problems I plan to replace this car with either the new golf or one of the hybrids. Pity the fed/state doesn't give diesels the same tax $$$ consideration hybrids get.

Have you been keeping the old parts?

rdkern said:

Have you been keeping the old parts?

Click to expand...

No-I didn't ask-not sure i would know-the mechanic said he tested the plugs, the relay and the harness. The harness was intermittent but since the older ones are known to be a problem I wasn't surprised.

From the second mechanics notes the GP's weren't getting power because of the blown fuse. As for the "big relay" - I've not seen it mentioned anywhere- - and I've been looking on several sites.

I do have the bent, twisted remains of the second clutch I put in but that's another story.

How much does it cost to replace your starter? Can people do it themselvs?

Starting problems-cold and not so cold continued

OK-got my car back Tuesday-this time they replaced a control unit and a flat fuse. Car was started and driven several times from when finished Thurs until they said i could pick it up Tuesday.

Started fine for me, drove it Tues and Wed-has 3 cold starts-and several warm ones-fine. Called the service rep and said all was fine - -> fatal error. Wed PM it was a little hard to start-as if I hadn't let the GP's heat. I turned it off, tried again-good start but the CE light didn't go out. Drove halfway home, pulled over and turned it off for a few minutes, it restarted perfectly-no CE light. Drove about 1/10 mile-CE light came on.

Thurs AM-hard, cold start, CE light in about 20 seconds - called the dealer-it's going back as soon as they have a loaner for me.

I asked about the codes-each time it was a "glow plug heater" code. They are puzzled-the tech told me there isn't much else in the system.

The only other electrical weirdness I've had was 5 months ago my 60 month VW battery quit after 9 months. My roadside came and used a "hot start" - - like a defibrillator to start it before towing it in. Since then my starter over revs and my CD/radio works sporatically for no consistant reason I can figure out. Been meaning to replace it but haven't.

Nothing I've seen goes as far as these guys have already done.

Have an Opinion? Suggestion? Answer to my woes? I'm listening.

Thanks much-

Leaking Water Seperator Cap

First of all - Thanks for the posted information on this thread. Our 02' Jetta TDI had a hard starting problem. A 5-8 second crank after car would sit for a hour or more. After investigating the shudder valve, glow plugs, power to the glow plugs, and fuses I started looking for air bubbles. I found a air bubble approximately 1/2 inch in length in the clear fuel line at about the high point coming out of the filter heading towards the engine. I then started looking around all the fuel lines and filter and found that below my filter/water seperator it was wet with fuel. Which as it turned out was coming out of my filter/water seperator drain cap on the bottom of said filter. The cap was not tight and in fact would not go back on tight. A new filter/water seperator was purchased and put in place after viewing the fuel filter change video clip on this site, and problem solved.

Had I not read the information here on the site and not investigated on my own each item as I could (which was very simple to follow and do) I would have taken the car to the local VW dealer and had them charge me hundreds of dollars to find and fix the problem.

THANKS!

One potential cause that I haven't seen mentioned here are injectors.

I've been having problems lately with poor starting with lots of smoke lately. Timing was advanced and glowplugs are ok.

I'm wondering (and this would be especially true of older model years and very high mileage vehicles), what impact a poorly performing injector has on the starting process. Pretty major I suspect.

I just ran diesel purge through the system a couple of days ago but haven't started it since (I had to leave for the airport right away). I'm eager to find out the impact, if any.

Diesels use the temperature of the compressed air to ignite the fuel. The glo plugs only help to heat the air. If the block is cold, it sucks the heat away from the compressed air as the engine cranks until the compressed air temperature won't ignite the fuel when it is injected. You need three things to start a diesel: air, fuel, and cranking speed. Cold weather means the block sucks more heat away, and slows the cranking speed. You need a good battery, good compression, and light oil. Glo plugs only make it easier - cranking speed is the real magic.

Well, my friend just purchased an 01 Golf with 91k on it.
Its had the TB changed about 15k ago?? And timing was "said" to be good.

And the day after she bought it, (was warm when we picked it up, kinda bummed me out, but didnt want to think anything of it) she mentioned its VERY hard to start, (40ish degrees in an underground garage)

The other day, i got too see what VERY hard to start means..
2-3 MINUTES to get that thing started. LOTS of smoke during cranking...
(she doesnt drive it every day, as she has another vehicle for the time being)

Once the car starts, and engine is warm, it restarts like a charm! It can sit for 2-3 hrs and start fine, but 8+hrs, back to hell.

Now for the sherlock holmes stuff... I gotta get the car to my place and leave it sit over night.


Ive been doing some reasearch, and I will start with the easy stuff, anti-shudder valve, then check the glow plug fuse, un plug the coolant temp sender (im sure i could test it also), then test the glow plugs for resistance, then check over the harness. With 91k the intake should be cleaned (never done, and Im sure i can remove it and clean it myself)

As far as checking the timing, yes, i see that is a must, but I cant do that myself, so will have to find someone who can help with that.

The battery is good, optima redtop, maybe look into the same situation MinsJetta had, with the fuel filter.

I think that just about covers everything ive read. Anything i missed?
Thanks to all the great info and reads,
Chris