Rough Idle

[Cornelius]

 

Hi.

I need some advice on an ongoing issue regarding my Audi A4
2.0 TDI.

I bought the car about 4 months ago and within the first
week, the EGR valve packed in. Some of the gears on the plastic cog broke off completely.
This was replaced for me by the garage that I bought the car from.

Before the EGR packed in and even after it has been replaced,
I have noticed a bit of a shake when you start it up in the morning. This eventually
fades away as soon as the car reaches its optimum temperature at about 90
degrees C. So I started trouble shooting to see if I can sort this problem.

 

1. 
   I have unplugged the M.A.F sensor and notice
   that the shaking is almost non-existent, and that the car was driving a little
   bit smoother. I have taken the sensor out and gave it a good clean and
   re-plugged it in. I was back to having the same problem.

 

1. 
   I concluded that the sensor must be faulty, and
   therefore replaced it with a new sensor. Still the problem persists. However if
   I unplug the sensor, it runs smoother?

 

1. 
   I have tested the coolant temp sensor by reading
   the ECU with an OBD2 reader that I have. It seems like the sensor is doing its
   job according to the readings, because it is consistent with what the temp
   gauge is saying on dash.

 

Logic suggests that the MAF is co-dependent on something
that is clearly not doing its job. I hope that someone can suggest any other
avenues I can explore, before even considering talking about things like:

 

Duel mass flywheel, Engine mounts and oil pump issues.

 

Thanks

 

[Cornelius]

 

Hi.

I need some advice on an ongoing issue regarding my Audi A4

2.0 TDI.

I bought the car about 4 months ago and within the first

week, the EGR valve packed in. Some of the gears on the plastic cog broke off completely.

This was replaced for me by the garage that I bought the car from.

Before the EGR packed in and even after it has been replaced,

I have noticed a bit of a shake when you start it up in the morning. This eventually

fades away as soon as the car reaches its optimum temperature at about 90

degrees C. So I started trouble shooting to see if I can sort this problem.

 

1. I have unplugged the M.A.F sensor and notice

   that the shaking is almost non-existent, and that the car was driving a little

   bit smoother. I have taken the sensor out and gave it a good clean and

   re-plugged it in. I was back to having the same problem.

 

1. I concluded that the sensor must be faulty, and

   therefore replaced it with a new sensor. Still the problem persists. However if

   I unplug the sensor, it runs smoother?

 

1. I have tested the coolant temp sensor by reading

   the ECU with an OBD2 reader that I have. It seems like the sensor is doing its

   job according to the readings, because it is consistent with what the temp

   gauge is saying on dash.

 

Logic suggests that the MAF is co-dependent on something

that is clearly not doing its job. I hope that someone can suggest any other

avenues I can explore, before even considering talking about things like:

 

Duel mass flywheel, Engine mounts and oil pump issues.

 

Thanks

 

Hi All

 

Thought I might give you some feedback. Whilst I was waiting for some advise on my current topic for 2 weeks now, I have decided to take my car to a tuning specialist.

 

I was advised that this is a common problem with these Audi's and it took them well over a year to figure out what the cause was. In a nutshell, my cam belt has been replaced before I bought the car and I suspect the owner had issues with it since then, hence the reason he sold it.

 

The specialist knew strait away what was wrong after I confirmed that the cam belt had been changed, The reason was that the Exhaust cam timing was wrong!!!!. He explained that allot of people who does these jobs does not realize that the cam timing needs to be polished off via the diagnostics port after the job has been done.

 

Owners go on the internet and convince themselves that all sorts of horrible things have gone wrong, like DMF, oil pumps and even gear boxes.

 

In some cases and £8000 later the timing was all that was wrong.

 

I hope this will help anyone to sort out a similar problem, before spending stupid money, where a simple £50 will sort it.

[Tipp]

Hi Cornelius could you give that answer to me in lay mans terms I have 2007 A6 2.0l diesel automatic when starting it gives a vibration for 3 seconds then gone I have replaced some key and shaft that goes in to oil pump which was worn and ready to go a common problem I'm told but vibration still there when starting I wonder have I the same problem as you and info much appreciated thanks. 

[jimmufy@yahoo.co.uk]

Hi all , newbie here ,  just a little information about the idle I had a new cambelt and water pump at our local garage and after the car is running lovely and smooth and does still after doing 8000 miles, before the car ran very rough on idle , happy days 2.0 tdi