2004 Audi A4 with 2.5tdi V6

geneandbolly · 20-01-15, 05:00 PM

does anyone know how reliable this engine is? a friend of mine is going to
look at an A4 avant and i have no idea about this engine. it's only done 119k miles
and the story with it sounds genuine enough . .

thanks.

vorsprung durch technik · 20-01-15, 05:21 PM

I'v heard nothing but bad things Craig.Camshafts wear on early ones not sure about later one and it seems there is too much to go wrong and when it does your looking 4 figures to put right. The 1.9 tdi is a much better bet and are very very reliable Apart from N75 valves and the odd sensor.Sensors are cheap enough and N75 valve from G@S about £75.Plus you can chip a 1.9 to not far short of the V6 power wise.

Try Googling it you will see the negative comments.

missfire · 20-01-15, 05:33 PM

Yep heard about the soft cams until 2003/4 at some point. But also heard they ain't very economical at all if driven hard. May as well stick to petrol unless you get diesel for free. 2.7t! Perfectly economical in this day and age of global civilisation collapse/oversupplied energy market/tumbling/ed crude prices. Diesel engines are for vans!

msh · 20-01-15, 08:38 PM

Over here we can hear mostly negative comments as well - a lot of people write in internet that 1.9 is better etc. There are two main problems with it - first one - valvetrain requires oil according to VAG standard, specified to that engine, and second one, there sometimes happen some problems with fuel pump, either mechanical or electronic. As for valvetrain, some people believes that the change in 2003. should have made any difference, which means - they believe that these newer engines don't require good oil

Some today estimate that this engine has resource of about 350k km - in the past I've read that problems with poorly maintained engines begins @ 200k. My cousin bought early C5 A6 2.5 TDI avant with AT - he sold it recently, because it was second car in a family for three years - engine was working like clock - apart from maintenance and replacement of MAF, which could happen. I presume that those who don't have any problem, just drive and don't write bold comments in the internet - that's why there's that poor reputation.

If you seriously want to buy one - best way is by removing valve covers for inspection, which, of course, involves new gaskets, but most sellers, especially in the UK, shouldn't be willing to do that. Persons with experience might try to make assumptions from that small part of one camshaft that is visible through oil filler.

P.S. I remember that here was similar thread some time ago, with only positive comments

geneandbolly · 20-01-15, 11:17 PM

thanks for your comments chaps - he's going to view it with those thoughts in mind.

Davy 85-80 · 21-01-15, 10:14 AM

I have A late 2001 A6 quattro with the 2.5 V6 (180ps) and apart from the fuel economy (32-34 average, up to 40mpg on a long run) it has been awesome, got it at 112,000 changed the belts n pulleys and its now over 160,000 without missin a beat

simons2 · 21-01-15, 11:17 AM

I read lots before buying the 2.5tdi and bar the two points raised regarding soft cams and the diesel pump giving up it seemed a good car. I've owned passats with the 1.9 130bhp and the 140. Well one year on and I am happy, on a run I've had upto 49mpg @ 65mph. It delivers the power in a fantastic way a nice even spread (and if you chip it power comes on sooner) Change the oil every 10k or every year. Check to see if the cambelt, water pump and thermostat have been done as its about £700-1000 job unless you do it yourself.
Thus far I'm impressed.

Davy 85-80 · 21-01-15, 12:30 PM

Quote:

Originally Posted by simons2

I read lots before buying the 2.5tdi and bar the two points raised regarding soft cams and the diesel pump giving up it seemed a good car. I've owned passats with the 1.9 130bhp and the 140. Well one year on and I am happy, on a run I've had upto 49mpg @ 65mph. It delivers the power in a fantastic way a nice even spread (and if you chip it power comes on sooner) Change the oil every 10k or every year. Check to see if the cambelt, water pump and thermostat have been done as its about £700-1000 job unless you do it yourself.
Thus far I'm impressed.

Agree on the cambelt job, I had mine done when the thermostat went, cost was almost £1000 from a VW dealer for all belt pulley's and pump. but I got lucky as it hadnt been done since new, contrary to the "history"

simons2 · 21-01-15, 03:24 PM

Davy 85-80 I wonder if there was some confusion to do with when the belts needed changing because it seems Audi first said 100K then they said 8 years. So how over due was yours!!

missfire · 21-01-15, 03:59 PM

Quote:

Originally Posted by Davy 85-80

Agree on the cambelt job, I had mine done when the thermostat went, cost was almost £1000 from a VW dealer for all belt pulley's and pump. but I got lucky as it hadnt been done since new, contrary to the "history"

I've wondered that myself, how hard is it to tick the 'toothed belt' check box? A damned sight easier than it is to do the belt and pump change that's for sure.

20-01-15, 11:17 PM	#5
geneandbolly 4 ring whore! Classic Audi Club Member Join Date: Sep 2011 Location: The Psychiatric Ward, North Ayrshire Posts: 7,490	thanks for your comments chaps - he's going to view it with those thoughts in mind. __________________ 1997 Audi S6 Ruby Red

21-01-15, 10:14 AM	#6
Davy 85-80 Grown up member Classic Audi Club Member Join Date: Sep 2009 Location: Scotland Posts: 64	I have A late 2001 A6 quattro with the 2.5 V6 (180ps) and apart from the fuel economy (32-34 average, up to 40mpg on a long run) it has been awesome, got it at 112,000 changed the belts n pulleys and its now over 160,000 without missin a beat __________________ 1985, 80, slighty modified 1986 80 Quattro Project 2001 A6 Quattro Sport TDi and a few Kawasakis

20-01-15, 05:21 PM	#2
vorsprung durch technik 4 ring whore! Classic Audi Club Member Join Date: Feb 2014 Location: Near Watford. Posts: 7,762	I'v heard nothing but bad things Craig.Camshafts wear on early ones not sure about later one and it seems there is too much to go wrong and when it does your looking 4 figures to put right. The 1.9 tdi is a much better bet and are very very reliable Apart from N75 valves and the odd sensor.Sensors are cheap enough and N75 valve from G@S about £75.Plus you can chip a 1.9 to not far short of the V6 power wise. Try Googling it you will see the negative comments.

20-01-15, 05:33 PM	#3
missfire making wooden things Classic Audi Club Member Join Date: Dec 2009 Location: cow land Posts: 8,156	Yep heard about the soft cams until 2003/4 at some point. But also heard they ain't very economical at all if driven hard. May as well stick to petrol unless you get diesel for free. 2.7t! Perfectly economical in this day and age of global civilisation collapse/oversupplied energy market/tumbling/ed crude prices. Diesel engines are for vans!

20-01-15, 08:38 PM	#4
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	Over here we can hear mostly negative comments as well - a lot of people write in internet that 1.9 is better etc. There are two main problems with it - first one - valvetrain requires oil according to VAG standard, specified to that engine, and second one, there sometimes happen some problems with fuel pump, either mechanical or electronic. As for valvetrain, some people believes that the change in 2003. should have made any difference, which means - they believe that these newer engines don't require good oil Some today estimate that this engine has resource of about 350k km - in the past I've read that problems with poorly maintained engines begins @ 200k. My cousin bought early C5 A6 2.5 TDI avant with AT - he sold it recently, because it was second car in a family for three years - engine was working like clock - apart from maintenance and replacement of MAF, which could happen. I presume that those who don't have any problem, just drive and don't write bold comments in the internet - that's why there's that poor reputation. If you seriously want to buy one - best way is by removing valve covers for inspection, which, of course, involves new gaskets, but most sellers, especially in the UK, shouldn't be willing to do that. Persons with experience might try to make assumptions from that small part of one camshaft that is visible through oil filler. P.S. I remember that here was similar thread some time ago, with only positive comments

21-01-15, 11:17 AM	#7
simons2 Grown up member Classic Audi Club Member Join Date: Jun 2012 Location: ireland Posts: 291	I read lots before buying the 2.5tdi and bar the two points raised regarding soft cams and the diesel pump giving up it seemed a good car. I've owned passats with the 1.9 130bhp and the 140. Well one year on and I am happy, on a run I've had upto 49mpg @ 65mph. It delivers the power in a fantastic way a nice even spread (and if you chip it power comes on sooner) Change the oil every 10k or every year. Check to see if the cambelt, water pump and thermostat have been done as its about £700-1000 job unless you do it yourself. Thus far I'm impressed.

21-01-15, 03:24 PM	#9
simons2 Grown up member Classic Audi Club Member Join Date: Jun 2012 Location: ireland Posts: 291	Davy 85-80 I wonder if there was some confusion to do with when the belts needed changing because it seems Audi first said 100K then they said 8 years. So how over due was yours!!