Frozen Diesel?

Scotty #

2001 Audi A4 1.9 TDI

Starts, runs smooth for 2-3 seconds, dies. Could this be frozen diesel?

...or, could it be related to a problem I had last week where when I went up a gear there was almost zero power until the turbo kicked in. When the car was ticking over it reved fine. It was ONLY when going up the gears. This problem seemed to go away again after a few hours.

Ty for any advice/suggestions!

v300

Possibly mushy diesel, or more likely a high pressure pump problem...
Are you running bio-diesel or vegetable cooking oil as fuel ? Big problems in this weather if you do.

Time to spend some money and get her looked at properly
before the barstool experts convince you the engine is shagged
and you need a new car.

who the fug

Can not see the oil companies being that stupid, or have the muppets forgotten what happened in 1979 /1980.

If you have forzen diesel then name and shame the garage

bryaner

Sounds like air mass meter problem or egr valve stuffed up not a big prob if either or both

Tragedy

"Like most fuels, diesel is a mix of hydrocarbons, and the components have different freezing points. For Number 2 diesel, as the ambient temperatures drop toward 32 degrees F (0 degrees C), it begins to cloud, due to the paraffin in the fuel solidifying. As the temperatures drop below 32 F, the molecules combine into solids, large enough to be stopped by the filter. This is known as the gel point, and generally occurs about 15 degrees F (-9.5 degrees C) below the cloud point.

This wax then forms a coating on the filter which results in a loss of engine power. The same thing happens on starting an engine when the temperature is below freezing. The filter becomes almost instantly coated with wax - usually, enough fuel gets through to allow the engine to idle, but not attain operating RPM. There are two common ways to overcome this: one is a diesel additive, the other is a fuel heater."

spadder

Tragedy wrote: »

" There are two common ways to overcome this: one is a diesel additive, the other is a fuel heater."

or move to Spain

bryaner

Are there not filter head heaters on these models anyway?

craichoe

Tragedy wrote: »

"Like most fuels, diesel is a mix of hydrocarbons, and the components have different freezing points. For Number 2 diesel, as the ambient temperatures drop toward 32 degrees F (0 degrees C), it begins to cloud, due to the paraffin in the fuel solidifying. As the temperatures drop below 32 F, the molecules combine into solids, large enough to be stopped by the filter. This is known as the gel point, and generally occurs about 15 degrees F (-9.5 degrees C) below the cloud point.

This wax then forms a coating on the filter which results in a loss of engine power. The same thing happens on starting an engine when the temperature is below freezing. The filter becomes almost instantly coated with wax - usually, enough fuel gets through to allow the engine to idle, but not attain operating RPM. There are two common ways to overcome this: one is a diesel additive, the other is a fuel heater."

Doubt it,

I was in Duisberg last year and it was -19 degrees Celcius, had no issues whatsover with my 1.9TDI.

Besides the freezing my backside off.

peasant

Tragedy wrote: »

"Like most fuels, diesel is a mix of hydrocarbons, and the components have different freezing points. For Number 2 diesel, as the ambient temperatures drop toward 32 degrees F (0 degrees C), it begins to cloud, due to the paraffin in the fuel solidifying. As the temperatures drop below 32 F, the molecules combine into solids, large enough to be stopped by the filter. This is known as the gel point, and generally occurs about 15 degrees F (-9.5 degrees C) below the cloud point.

This wax then forms a coating on the filter which results in a loss of engine power. The same thing happens on starting an engine when the temperature is below freezing. The filter becomes almost instantly coated with wax - usually, enough fuel gets through to allow the engine to idle, but not attain operating RPM. There are two common ways to overcome this: one is a diesel additive, the other is a fuel heater."

Also, the filter will gradually fill with water (from condensation in the tank) which can and will freeze.

Some filters have a drain screw at the bottom to let the water out (water, not ice )

BlackWizard

Last week I had some dicey starts in my 1.9 diesel. So on the weekend I added in some fuel additive and it's been starting fine. Not even a grumble off it.

The glowplugs are taking nearly 8 seconds to go out though. So the engine must really be cold.

Tragedy

craichoe wrote: »

Doubt it,

I was in Duisberg last year and it was -19 degrees Celcius, had no issues whatsover with my 1.9TDI.

Besides the freezing my backside off.

There are different types of diesel!

Scotty #

Thanks all for the replies.

bryaner wrote: »

Sounds like air mass meter problem or egr valve stuffed up not a big prob if either or both

The air mass meter was suggested to me last week. Is this a problem that can come and go? Is todays problem also a symptom?

I left the car this morning and took the van so no idea if it's still the same. Was taking to a friend who called the AA to her car that wouldn't start and they put something in the fuel and said it's all they've been doing all week.

Tragedy

Scotty # wrote: »

Thanks all for the replies.

The air mass meter was suggested to me last week. Is this a problem that can come and go? Is todays problem also a symptom?

I left the car this morning and took the van so no idea if it's still the same. Was taking to a friend who called the AA to her car that wouldn't start and they put something in the fuel and said it's all they've been doing all week.

The MAF on my car deteriorating(as they are wont to do) leads to almost no power until Turbo kicks in.

However, MAF shouldn't stop the car from starting, it will just under or over fuel.

Scotty #

Tragedy wrote: »

However, MAF shouldn't stop the car from starting, it will just under or over fuel.

It is starting.... but only runs for a few seconds before dying again. From reading around it does sound like frozen diesel (thought the van started fine). Suppose I'll just have to wait for temp to rise to know for sure. Hope I haven't done any further damage trying it??

BlackWizard

What if you press the pedal when starting. Does that help keep it going?

10 KY 01

Buy a new Audi, its the biz.......

BlackWizard

10 KY 01 wrote: »

Buy a new Audi, its the biz.......

You should buy a share in a private helicopter. I think it's the biz.

bryaner

Scotty # wrote: »

Thanks all for the replies.

The air mass meter was suggested to me last week. Is this a problem that can come and go? Is todays problem also a symptom?

I left the car this morning and took the van so no idea if it's still the same. Was taking to a friend who called the AA to her car that wouldn't start and they put something in the fuel and said it's all they've been doing all week.

Air mass meters give a lot of trouble and the problem can come and go

but if the AA say that's all they have been doing all week then thats good

for me id try what they say, it's worth a shot to nothing

bryaner

10 KY 01 wrote: »

Buy a new Audi, its the biz.......

Help full bell end

teednab-el

does anyone turn the key one notch for a few secs before starting? I find it helps me start my A4 TDi quicker than waiting for glow plugs to go out.

louis346789

i am running v70 on 100% biodiesel. similar problem on Christmas eve ( -5 deg). stopped after half mile and would only restart for about half minute.
Put 100 w bulb in box under fuel tank each night since then. sorted the problem.

GTE

teednab-el wrote: »

does anyone turn the key one notch for a few secs before starting? I find it helps me start my A4 TDi quicker than waiting for glow plugs to go out.

Sorry but Im confused with what you mean. If you turn it a notch nothing happens, another notch then the GP's come on another then the engine starts.
What exactly do you mean?

The engine wont start easier by cutting the GP cycle short. The car should start without them, but the ECU has them on for a certain time for a reason. Today it was 8 to 10 seconds.

The glow plugs in my barge have only started working this week due to a messy sensor which I think I got working again and the GP assisted starts are a dream now. From 20 second crank times in this weather to 2 or 3 second after the GP's did their thang.

teednab-el

bbk wrote: »

Sorry but Im confused with what you mean. If you turn it a notch nothing happens, another notch then the GP's come on another then the engine starts.
What exactly do you mean?

The engine wont start easier by cutting the GP cycle short. The car should start without them, but the ECU has them on for a certain time for a reason. Today it was 8 to 10 seconds.

The glow plugs in my barge have only started working this week due to a messy sensor which I think I got working again and the GP assisted starts are a dream now. From 20 second crank times in this weather to 2 or 3 second after the GP's did their thang.

Turn it one notch and hold it in that position, do not let go, you hear a slight click. Hold it for a few secs and then start it. Im not sure if this works for everyone but it works for me in these cold mornings. Someone told me this before and I decided to try it. Now it starts much better.

bryaner

teednab-el wrote: »

does anyone turn the key one notch for a few secs before starting? I find it helps me start my A4 TDi quicker than waiting for glow plugs to go out.

The tank in the pump starts on that notch so maybe it helps

ianobrien

One simple trick is to park the car right next (I mean 2 inches away max) to the house, or if that's not suitable, right next to a large hedge/wall.

The heat from the house and the shade from the wind offered by the house/wall/hedge may be enough to stop the wind chill from cooling the diesel. Also, make sure that your fuel line is not after dropping, exposing it to cold winds under the car.

If you're home heating oil is Kerosene, throw a small bit (enough for a 1% solution in Diesel I reckon might do) into the tank. That will depress the point at which the diesel starts to solidify (I think that the kerosene forms an azeotropic mixture with the paraffin thus preventing the paraffin from solidifying, but it's been so long since I last studied organic azeotropic distillation.....)

If you throw in too much, and you blow the fuel pump or get stopped by Customs or Excise, it's on your head.

GTE

teednab-el wrote: »

Turn it one notch and hold it in that position, do not let go, you hear a slight click. Hold it for a few secs and then start it. Im not sure if this works for everyone but it works for me in these cold mornings. Someone told me this before and I decided to try it. Now it starts much better.

Hmmm interesting It should work for me too. I have basically the same engine. Ill try that with the GP's tomorrow because this morning was particularly cold and it took longer to get going even with the glow plugs. And to chime in with another post, this morning when the car didnt start great the car was about a meter or two further from the house then normal.

PaulKK

Double or triple heat the plugs if you want it to start easily.


I changed my heater plugs in my 1.9TDI recently and double heat on these mornings and she starts no problem.

GTE

PaulKK wrote: »

Double or triple heat the plugs if you want it to start easily.


I changed my heater plugs in my 1.9TDI recently and double heat on these mornings and she starts no problem.

Thats a good tip. I really need this new temp sensor though. My black one is shagged to high heaven. But I cant get to the VW dealer to get the new green one or the coolant to top up afterwards.
Anyway, thats for a different thread.

craichoe

Tragedy wrote: »

There are different types of diesel!

Its West Germany man .. hardly different diesel to Ireland ffs.

BlackWizard

teednab-el wrote: »

Turn it one notch and hold it in that position, do not let go, you hear a slight click. Hold it for a few secs and then start it. Im not sure if this works for everyone but it works for me in these cold mornings. Someone told me this before and I decided to try it. Now it starts much better.

That click you are hearing is the glowplugs turning off. You should see a light on the dash go out when it happens.

Also turning it once notch shouldn't turn on the glowplugs. I thought the second notch does that So now I'm thinking the glowplugs turn on during the first notch. I'll test this when going home

GTE

BlackWizard wrote: »

So now I'm thinking the glowplugs turn on during the first notch. I'll test this when going home

The GP's dont come on on notch one on a VAG diesel of that year anyway. If they did the light should be on. I think the argument is that something else does, like maybe a fuel pump gets primed before everything else. Maybe the fuel pump is a low power unit that can be switch on before the next notch when the battery activates the whole shoot and gallery of things in your car.

Having said that, cutting a GP cycle short wont help you. If something does happen in the first notch combining that with a full GP cycle should work better for you engine.

Mind you, Im no mechanic.

congo_90

Sorry to thread jack but what additive works for diesal? Noticed a few rough starts lately at - 9c outside temp. didn't think diesal froze till -40? I cannot remember where I heard that figure from though.

GTE

STP have one, I think thats the brand. Diesel treatment. Big silver bottle. It has a cardboard cutout of injectors on it.

I admit I used that when I first got my car. It was used so I figured I would clean the engine out.

I think it did give a positive effect to starting the engine. I think, but I may be trying to justify the 20 quid I spent on it lol.

Tragedy

craichoe wrote: »

Its West Germany man .. hardly different diesel to Ireland ffs.

There's low temperature diesel, Germany always has cold winters ffs

Hence why german cars have winter tyres even though it's unknown in ireland ffs

Darragh29

Scotty # wrote: »

2001 Audi A4 1.9 TDI

Starts, runs smooth for 2-3 seconds, dies. Could this be frozen diesel?

...or, could it be related to a problem I had last week where when I went up a gear there was almost zero power until the turbo kicked in. When the car was ticking over it reved fine. It was ONLY when going up the gears. This problem seemed to go away again after a few hours.

Ty for any advice/suggestions!

OP I think your air intake for the engine could be blocked with snow or ice and the engine can't breathe. Forget frozen fuel being the problem. If you can open your bonnet, take a pic of the engine bay and post it up here I can tell you where the problem might be, if you can take a pic of the air intake/air filter area...

meathstevie

As far as I know diesel all over Western Europe should be good to -20 C. If you think it's freezing in your tank throw a bit of petrol in, personally I wouldn't go over much more than two litre in a full fifty litre diesel tank. It lowers the freezing point of the diesel and the added bonus is that there's excise paid on it and customs can't give you any jib.

ianobrien

I was talking to somebody today at work about the diesel and the weather, and especially bio-diesel.

(This gets complicated very quickly so be careful, and I'm annoyed with myself for not coming up with this earlier. It's the result of taking Lunch with an Organic Chemist, and I'd forgotten some of my Organic Chemistry)

The problem with the bio-diesel is the ester group on the end of the organic chain. In the cold weather, the diesel molecules align themselves with the ester groups all pointing at each other as the hydrophilic enter groups surround the ice that has frozen in the diesel. The result, a soapy fuel, because as every Junior Cert Science student knows, Soap is just ester groups at the end of an organic chain.

The ice that has formed in the diesel is extremely small crystals (I'm talking micron size here, ie 0.001mm), but it is large enough for the individual organic molecules to align themselves on and form the soap

The result for us motorists is that you'll get a soap in the bio-diesel, clogging the filters.

Darragh29

Lads this isn't a fuel problem, it's an engine aspiration problem. If the fuel was frozen, the car wouldn't start full stop. The air tract into or out of the engine is obstructed by snow. OP, also check your exhaust isn't blocked, as this will cause the same engine aspiration problem.

OP some cars, the air intake into the car is at the top of the bonnet just at the base of the window wipers. This area can get blocked with snow very easy, make sure here is well clear of snow and ice.

rex-x

Joys of a common rail, dont even need the glow plugs and have an in tank heater and inline fuel heater as standard, pug hdi FTW starts first tip of the key :cool:

Tragedy

Darragh29 wrote: »

Lads this isn't a fuel problem, it's an engine aspiration problem. If the fuel was frozen, the car wouldn't start full stop. The air tract into or out of the engine is obstructed by snow. OP, also check your exhaust isn't blocked, as this will cause the same engine aspiration problem.

OP some cars, the air intake into the car is at the top of the bonnet just at the base of the window wipers. This area can get blocked with snow very easy, make sure here is well clear of snow and ice.

I don't think anyone said the diesel was frozen, just it was turning to slush and clogging fuel filter. Which happens.

Darragh29

Tragedy wrote: »

I don't think anyone said the diesel was frozen, just it was turning to slush and clogging fuel filter. Which happens.

Yes it happens and it doesn't cause the type of symptoms that are being complained of here. What causes the complaint here is the engine not being able to aspirate normally due to a blockage in either the inlet or exhaust tract.

MugMugs

meathstevie wrote: »

As far as I know diesel all over Western Europe should be good to -20 C. If you think it's freezing in your tank throw a bit of petrol in, personally I wouldn't go over much more than two litre in a full fifty litre diesel tank. It lowers the freezing point of the diesel .

+1

Scotty #

Tried it last night, -6 on the dash, ran for 10-12 seconds (no revs) and then died. Didn't try again.

Got home this evening, car in sun all day, -2 on dash, started fine and has been running fine ever since.

(still need to get the mass air meter looked at though)

Thanks for all the replies.

Tragedy

Darragh29 wrote: »

Yes it happens and it doesn't cause the type of symptoms that are being complained of here. What causes the complaint here is the engine not being able to aspirate normally due to a blockage in either the inlet or exhaust tract.

If you were right, it wouldn't have fixed itself by warming only to -2.

Still think it was a clogged filter!

fraz1971

10 KY 01 wrote: »

Buy a new Audi, its the biz.......

Audi's are crap. BMW are far superior in every respect. The 6 series is da biz gobsheen. So much for your one upmanship!

thereitisgone

It is most likely the diesel, i live in Finland and we have winter and summer diesel which ye would have all year round. Over here all petrol stations change over to winter diesel in October November and diesel drivers run down their tanks of summer diesel and replace it with the winter diesel. Germany and a lot of eastern Europe would have the same system. So with the temps ye are having over there at the moment it is probably the diesel causing the problems.

Scotty #

Tragedy wrote: »

If you were right, it wouldn't have fixed itself by warming only to -2.

Still think it was a clogged filter!

In fairness, the temp prolly would have been above Zero during the day. That -2 was at 6PM

Tragedy

Scotty # wrote: »

In fairness, the temp prolly would have been above Zero during the day. That -2 was at 6PM

It went to about 2 degrees here yesterday, on my car at least, not one bit of ice, frozen slush or snow melted(and my car was out in the bit of sun we have here!)