audi avant tdi sport diesel, 2003,engine races when cold

[darcar]

Hi all, can anyone help, when i first start up in the mornings, the engines races briefly, and i don't have my foot on the accelerator. any ideas on this problem, someone mentioned a airflow sensor could be needed, euro carparts want £102 for one,
as i'm on a pension,, thats out of the question.
thankyou,

 

[quattro tony]

Hi ive come across this problem before on the pd engine and it was the coolant temp switch at fault, carnt see how the air mass meter would cause it but i may be wrong. If you can do a scan of the ecu should pick up the fault, but the ones ive had , new temp switch had fixed it.

 

[sniffy_smiffy]

If you suspect MAF (Airflow) then unplug it from the connector the car will ignore its readings and run a default set of data through the ECU, then start her up & see if it makes a difference?

If not then look elsewhere I.E CTS (Coolant Temp Sender/Sensor) or further...

If you cant find the problem then you really need someone to scan your E.C.U with VAGcom / VCDS software for errors as this should report a dodgy component.

There is a VCDS / VAGcom section on this forum to find local members who will help you out.
People are very helpful on ASN with that sort of thing. :icon_thumright:

Good Luck.

If it doesnt't work out @ least the bus tickets are free.......
Sorry only playing could not resist that one..

 

[BILKO1]

Mine done the same when i bought it and it was the coolant temp sensor. It will show up in Vcds and other diagnostic equipment. If doing it yourself (quite easy) buy the plastic clip and rubber o ring too, about £25 all in.

 

[sniffy_smiffy]

The CTS was a pain in the *** on my old v5 Golf! I had to replace most of my engine coolant that ended up on my driveway...

You had to have ladies hands to get at it.

Was like trying to paint your hallway through your letterbox !!!

I guess it is easier on the Audi's ?? Have not had to do it yet so don't know?

 

[vinesh]

Always best to buy some G12 fluid.

On my 1.9tdi, it drained most of the fluid.

 

[Garfie]

Sounds like the coolant temperature sensor to me too. My Golf used to occasionally rev up briefly when I started it as the wiring in the plug to the CTS was dodgy. If it reved up I would just pop the bonnet and wiggle the wires and connector and it would be fine again for a few weeks before it went again.

I'd therefore try checking the connection to yours first before replacing the sensor.

On a 130 PD its located on the back of the engine about 8-10 inches down, accessed from the passenger side, you can't really see it, you'll have to feel for it. Access is easier with the rigid boost pipe removed and the flexible section unclipped but as mentioned above its not a job for someone with big hands!!

 

[darcar]

Thankyou all for your reply's, i will check the coolant sensor, cheers