Hi all, I decided to start a new thread about my car troubles to see if any one had any ideas as to the problem without old posts clouding the issue.

I have a 1.9tdi PD130 (AWX) and ever since I bought it privately off some dodgy bloke I have had power and fuel economy problems.

The symptoms:

1) It feels like there’s a throttle lag. If I press the accelerator quickly to half way, the engine will not respond for about 1 second.

2) There is a loss in power, it’s feels like 90bhp. It is not limp mode as it’s still there when I cycle the ignition.

3) Fuel consumption is bad - 40mpg average when I should be getting 50.

4) There is a 3-4 drops a day oil leak.

Tests I’ve done:

a) I visually checked the vacuum leads but not all. The braided line to the EGR valve is chaffed but still intact.

b.) Checked the VNT actuator. I took the line off the actuator and using a clean washer tube sucked through it. The actuator moved up 10mm.

c) Watching the VNT actuator I got a mate to start the car. The actuator moved up about 20mm. However it doesn’t move unless you give it a lot of throttle and only about 10-15mm downwards in one quick movement.

d) EGR valve was covered in oil which I cleaned and has some oil on it again. Took off hose at air inlet, there is a small pool of oil in the valve.

e) Tested the EGR. I connected a tube to the EGR and sucked. Nothing appeared to move. There was no soft click sound when I released the ‘vacuum’.

f) I have not seen the EGR intake valve actuator work when the car is started, running or when switched off.

g) At idle, when the accelerator is pressed the EGR actuator ‘farts’ for want of a better word.

h) I disconnected the MAF and drove the car. It felt like I had 40bhp with no turbo which I guess was ‘limp mode’.

i) I can hear the turbo spooling normally.

After asking someone with VCDS to help, they charged me £20, told me there was no faults listed, did a scan and never emailed me the results. Lesson Number 2 - trust no-one.

I got a lead from Gendan and downloaded VCDS Lite which I have not yet registered. But I did get the following results: (in Measuring Blocks)

001 - Coolant temp always seems to be lower than the dash gauge. For example I tested after a 50 mile run, dash says 90°C, VCDS coolant temp says 79.2°C.

003 - after 50 mile run, off for 15mins then re-started to idle readings as follows:

819rpm 250maf specified 420maf actual 4.8% EGR

1900rpm 230maf specified 220maf actual 64% EGR

Note: I tried this later, I blipped the throttle (i.e. returned to idle) EGR rose to 57% and held at this value at idle.

010 - actual charge pressure usually stays within 100 of the specified figure. This was observed with the car in motion, going through the gears under different acceleration rates. Highest figures within those specified.

015 - fuel consumption:

1000rpm 5.8inj qty actual 3.6inj qty requested

2000rpm 8.2inj qty actual 8.0inj qty requested

With the information can anyone offer any ideas, or suggest a further test?

I intend to replace the coolant temp sensor for a start if anyone to tell me where they are?

Many thanks for any assistance offered!

Why dont you take it to a workshop?

This thread will show you where the coolant sensor is located and how to change it

Why dont you take it to a workshop?

I would rather save my money and figure out the problems myself with the aid of great people and forums like this one ;-)

This thread will show you where the coolant sensor is located and how to change it

Thanks mate.

hi there, i put a thread on a bit ago about int power loss but got no help just a pointless comment from cown, im used to better things and also havent got the vcds as i use a mercedes system for work so the outlay isnt warranted, as for taking it into a dealer that is a waste of time,good at fleecing you while not fixing the fault,can you tell me where you got the cable or links,as i dont use the car anymore but like yours has a power loss, i done all the checks and with a lesser scanner found nothing logged, but i did speak to a specialist who said it will be the turbo sticking, as there is nothing obvious logged or visually wrong and after seeing a thread on the workings on the vnt im coming round to the fact that turbo is sticking and not giving full boost, not planing to keep it for much longer as im fed up with it

hope you get to the bottom of it.

Hi all, I decided to start a new thread about my car troubles to see if any one had any ideas as to the problem without old posts clouding the issue.

I have a 1.9tdi PD130 (AWX) and ever since I bought it privately off some dodgy bloke I have had power and fuel economy problems.

The symptoms:

1) It feels like there’s a throttle lag. If I press the accelerator quickly to half way, the engine will not respond for about 1 second.

2) There is a loss in power, it’s feels like 90bhp. It is not limp mode as it’s still there when I cycle the ignition.

3) Fuel consumption is bad - 40mpg average when I should be getting 50.

4) There is a 3-4 drops a day oil leak.

Tests I’ve done:

a) I visually checked the vacuum leads but not all. The braided line to the EGR valve is chaffed but still intact.

b.) Checked the VNT actuator. I took the line off the actuator and using a clean washer tube sucked through it. The actuator moved up 10mm.

c) Watching the VNT actuator I got a mate to start the car. The actuator moved up about 20mm. However it doesn’t move unless you give it a lot of throttle and only about 10-15mm downwards in one quick movement.

d) EGR valve was covered in oil which I cleaned and has some oil on it again. Took off hose at air inlet, there is a small pool of oil in the valve.

e) Tested the EGR. I connected a tube to the EGR and sucked. Nothing appeared to move. There was no soft click sound when I released the ‘vacuum’.

f) I have not seen the EGR intake valve actuator work when the car is started, running or when switched off.

g) At idle, when the accelerator is pressed the EGR actuator ‘farts’ for want of a better word.

h) I disconnected the MAF and drove the car. It felt like I had 40bhp with no turbo which I guess was ‘limp mode’.

i) I can hear the turbo spooling normally.

After asking someone with VCDS to help, they charged me £20, told me there was no faults listed, did a scan and never emailed me the results. Lesson Number 2 - trust no-one.

I got a lead from Gendan and downloaded VCDS Lite which I have not yet registered. But I did get the following results: (in Measuring Blocks)

001 - Coolant temp always seems to be lower than the dash gauge. For example I tested after a 50 mile run, dash says 90°C, VCDS coolant temp says 79.2°C.

003 - after 50 mile run, off for 15mins then re-started to idle readings as follows:

819rpm 250maf specified 420maf actual 4.8% EGR

1900rpm 230maf specified 220maf actual 64% EGR

Note: I tried this later, I blipped the throttle (i.e. returned to idle) EGR rose to 57% and held at this value at idle.

010 - actual charge pressure usually stays within 100 of the specified figure. This was observed with the car in motion, going through the gears under different acceleration rates. Highest figures within those specified.

015 - fuel consumption:

1000rpm 5.8inj qty actual 3.6inj qty requested

2000rpm 8.2inj qty actual 8.0inj qty requested

With the information can anyone offer any ideas, or suggest a further test?

I intend to replace the coolant temp sensor for a start if anyone to tell me where they are?

Many thanks for any assistance offered!

Strongman,

Here's a video showing how the VNT actuator working properly (viewing it upside down makes more sense):

.

Get a mate to start the car, look to see if actuator moves up about 20mm. It should also move in sync with throttle etc.

Assuming you have a B5.5 Passat up to 2005 then:

VCDS-Lite available for free download here: ($99 will unlock a lot of features!)

http://www.ross-tech.com/vcds-lite/download/index.html

Cable available here for £20 delivered: (you must make sure it will fit your car - connection under steering wheel)

http://www.gendan.co.uk/product_VAGUSB.html