Cold running query

macpdm

macpdm

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Afternoon all

I would be grateful for your comments on the following query please.When starting my 2000 A3 1.8T sport and driving away from cold the engine feels lumpy to the point where the car is almost kangarooing.I dip the clutch and add a few revs to counter this but after a few mins of running all seems fine. I have been getting an ESP light on from time to time and I thought this was the sensor in the brake servo but Im wondering now if there is any connection?

Many thanks in advance for your attention.
 
I think the ESP brake servo issue is just a coincidence mate. I had cold startup issues 2 years ago that were fixed with 4 new coil packs.

Coil packs and spark plugs should be your first port of call, do you know when they were last replaced?
 
Thanks guys I had Audi replace the coil packs under warranty a couple of months ago so probably not that.I had a look at one of the plugs which by using a magnifying glass looked very slightly rounded off at the contact point.Does the MAF need replacing or can it be cleaned & can you test it to see if its faulty ?
 
macpdm said:
Thanks guys I had Audi replace the coil packs under warranty a couple of months ago so probably not that.I had a look at one of the plugs which were very slightly rounded off and perhaps could do with changing.Does the MAF need replacing or can it be cleaned & can you test it to see if its faulty ?
Click to expand...

My knowledge of the different A3 engines isn't as good as the S3 engines i'm afraid but on the S3 you can run the car with the MAF unplugged. Try unplugging your MAF in the morning before you start the car and drive the car with it unplugged (it wont do any harm) and see if it's running better.

Do you know wher to unplug the MAF?
 
Westy said:
My knowledge of the different A3 engines isn't as good as the S3 engines i'm afraid but on the S3 you can run the car with the MAF unplugged. Try unplugging your MAF in the morning before you start the car and drive the car with it unplugged (it wont do any harm) and see if it's running better.

Do you know wher to unplug the MAF?
Click to expand...

Cheers Westy

I will try unplugging it I assume its over on the RHS near the airbox ?
 
Westy said:
yeah that's it. Just outside the airbox, you cant miss the connector.
Click to expand...

Yes thats the one I unplugged it when I removed the airbox at the weekend to reconnect the rear washer pipe.Bet I havent got the required torx bits though.
 
can u not clean with an air can? (like PC air spray for cleaning fans etc IT geeks will know what i mean)
 
audi upgrades
Its going to have to wait until I can afford a replacement rather than risk cleaning it.Just found out the central locking on the wifes Mk5 Fiesta has packed up, the two bathrooms in my house are leaking and my daughter wants to go to Portugal with her mate :crying:

I will try unplugging it though and see what difference it makes.Apparently though this will put the check engine light on.
 
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macpdm said:
Its going to have to wait until I can afford a replacement rather than risk cleaning it.Just found out the central locking on the wifes Mk5 Fiesta has packed up, the two bathrooms in my house are leaking and my daughter wants to go to Portugal with her mate :crying:

I will try unplugging it though and see what difference it makes.
Click to expand...

Feeling your pain, get some of this:

[url]http://www.ebay.co.uk/itm/electrical-contact-cleaner-spray-500ml-/380367102502?pt=UK_Car_Accessories_Car_Care_Cleaning&hash=item588fa56226#ht_500wt_969

[/URL]and try cleaning it. Worth a go for a fiver.
 
audi upgrades
macpdm said:
Thanks but fortunately I do have some electrical contact cleaner which I picked up from Halfords.Is it right that disconnecting it will put the check engine light on ?
Click to expand...

Yes, but it should go away one reconnected.
 
Interestingly I got in the car to go home and let it come off the (I assume) auto choke before setting off and it did seem better.I will try unplugging the MAF next.
 
Well I unplugged the MAF this morning and drove off from cold only a few hundred yards and it seemed worse yet no check light.I plugged it back in and it was the same for a short while then got better after a mile or two.

What does this mean ?
 
macpdm said:
Well I unplugged the MAF this morning and drove off from cold only a few hundred yards and it seemed worse yet no check light.I plugged it back in and it was the same for a short while then got better after a mile or two.

What does this mean ?
Click to expand...

I'd say that rules out the MAF then. I had cold start issues 2 years ago and when I unplugged the MAF it was the same. I fixed the issue by changing the coil packs. If you've got new coils I'd look at getting new spark plugs, they're cheap and if one of your plugs is a bit dodgy then it may be worth it.

When the engine is cold the spark may not be strong enough and that might be what's causing the issue.
 
Cheers buddy I will try that and see how I go I reckon they are due for a change anyway.
 
Have you thought about the temperature sensor?
 
macpdm said:
Afternoon all

I would be grateful for your comments on the following query please.When starting my 2000 A3 1.8T sport and driving away from cold the engine feels lumpy to the point where the car is almost kangarooing.I dip the clutch and add a few revs to counter this but after a few mins of running all seems fine. I have been getting an ESP light on from time to time and I thought this was the sensor in the brake servo but Im wondering now if there is any connection?

Many thanks in advance for your attention.
Click to expand...

Been having this recently as well, I'm glad it's not just me. Coils were done done by audi last year, car needs a service though, so perhaps it's the spark plugs. Coincidentally last time I scanned my car with VCDS, I had a brake related fault..
 
I had the same issue mate, Was a water temp sensor. Was yours a pig to start? Might be worth having a look at that.

J
 
Hmm a3tdi & spankys3 might have something here in that I notice my temp guage seems to take a long time to get to the centre of the dial.Its around 4 miles to get home from work with light traffic & NSL B roads and its still nowhere near the centre.Can people tell me how many miles they cover before the temp guage gets to the centre ?
 
There are two temperature sensors, one for the gauge on the dashboard and another for the ECU. The one for the ECU is notoriously troublesome and I'd plump for changing that before you go any further. It should have been a recall by Audi but they seem to have done their coil pack/corrosion/..... ignore the plebs and hope that they ****** off without contacting Watchdog. The symptoms for me, on a TDi, were that it would always start but the first few minutes would be extremely lumpy.
If you think that the engine is taking a long time to rise then this could be the thermostat sticking open. Try the same run with the heater/fan on full blast and if it takes even longer to rise then that suggest the thermostat.
 
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a3tdi2001 said:
There are two temperature sensors, one for the gauge on the dashboard and another for the ECU. The one for the ECU is notoriously troublesome and I'd plump for changing that before you go any further. It should have been a recall by Audi but they seem to have done their coil pack/corrosion/..... ignore the plebs and hope that they ****** off without contacting Watchdog. The symptoms for me, on a TDi, were that it would always start but the first few minutes would be extremely lumpy.
If you think that the engine is taking a long time to rise then this could be the thermostat sticking open. Try the same run with the heater/fan on full blast and if it takes even longer to rise then that suggest the thermostat.
Click to expand...

Many thanks

The temp sensor for the ECU is it expensive and where is it and how difficult is it to fit assuming Audi wont do it for free ?

Apologies for all the questions.
 
The sensor from Audi is around about £20 if I remember. Best to get a genuine one from the dealer. Not sure about where it is on a 1.8 petrol but there are loads of S3 guys on here who should be able to help.
 
Ok update:

As suggested I drove the car home for 15mins with heater & fan on full and the temp guage hardly moved above 62 - 63.Ten minutes later I got back in the car and drove back to work but I turned the fan & heater down to normal temp and speed.By the time I got to work which took 15 mins the temp guage was bang on 90.Im not certain what this means is the thermostat goosed as well as the temp sensor.Is the ECU temp sensor ok as the temp guage seems to be working ?
 
That would appear to show that the thermostat is sticking open slightly. It's job is to keep the engine temperature constant after it's warmed up. From what you've said I'd go with a new thermostat and o-ring, coolant temperature sensor (ECU) with o-ring and plastic clip, all from Audi. I'd do a flush/change of coolant while you're at it if there's no record of the coolant being changed? This is the correct coolant. Comma :: Productsguide, mix with de-ionised water.
 
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Thanks all

I dont actually know where the coolant temp sensor (ECU) is located ?
 
Much appreciated buddy thanks but am I right in thinking that there are two temp senders, one of which is for the temp guage ?
 
macpdm said:
Much appreciated buddy thanks but am I right in thinking that there are two temp senders, one of which is for the temp guage ?
Click to expand...

You're thinking of the thermostat. Try changing the temp sender that is the sensor that sits in the water pipe as it probably needs doing anyway plus its a lot easier than doing the thermostat. If you are still having problems after doing the temp sender then change the thermostat.
 
Westy said:
plus its a lot easier than doing the thermostat
Click to expand...

Understatement of the year!

Try finding somebody with really small hands and double jointed wrists, who also possesses the patience of a saint and has loads of knuckle joints and extension bars in his socket set...then it's easy to do the thermostat.
 
As the guys say, but my bet is that changing the temperature sensor won't fix the symptoms you describe in #32 above:)
 
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