Hi Guys,

First post here,

Octavia Scout 2.0l diesel, intermittent problem with acceleration, it gets worse under load, ie higher gear or going uphill. 
At a constant speed it does not have a noticeable problem. Don’t know a great deal about diesels and that’s where I get a bit stumped. I plugged a obd2 sensor in a couple of months ago when it first started and it came up as a fault with one of the glow plugs? Could this cause a problem like a misfire?  Plugged it in again since it got worse, and got these three fault codes up. I would of thought it was a MAF sensor or possibly a throttle position sensor, or injector. Is this a common fault if it is showing an open circuit are the glow plugs energised constantly and not just for cold starting?

Thanks 

Peter

Hi Guys, any input would be greatly appreciated. 
thanks. 

Bad glow plugs on a PD engine aren't worth replacing unless starting becomes an issue.

 

You don't detail your intermittent problem but by the sound of things the engine is demanding more fuel than the system can supply, possibly due to gradually clogging diesel filter.

9 hours ago, MicMac said:

Bad glow plugs on a PD engine aren't worth replacing unless starting becomes an issue.

 

You don't detail your intermittent problem but by the sound of things the engine is demanding more fuel than the system can supply, possibly due to gradually clogging diesel filter.

 Hi, 

would this not have a lack of fuel pressure and have a fault code showing?  Not used my obd2 scanner much and the glow plugs were the only fault I can see? Would the scanner show any relevant faults like this. 
 

cheers

What engine is in your car?

Not sure what you mean  it’s 2008 with a 2.0 litre diesel,  direct injection I think,  it does not have common rail injection. I think it is 160ps engine. Is that what you need?

A PD engine, code BKD I believe.

 

AFAIK low fuel pressure isn't flagged or at least until the engine won't run, I could be wrong.

 

The depth of scanning and reporting are dependent on the capabilities of the scanner.

 

Expand on juddering under load.

It seems like it is dropping a cylinder like a misfire or timing issue, but as there is no spark it ain’t timing issue. Juddering was not the best discription I could of given you. It’s like there is hardly any power in high gear. Sometimes it is really severe and the whole car is shaking under acceleration other times it is hardly noticeable. 

If it was a petrol car I would first think timing, spark,  or insufficient fuel or too much fuel, ie injectors sticking or sensors TPS or airflow sensor? 

Have a scan done with a proper diagnostic tester preferably VCDS or failing that at a garage with a Snap-on or similar one that can interrogate the various modules.

 

The toy testers wont tell you anything except standardised OBDII codes after a MIL light has been illuminated.

Interesting...

 

I have a similar issue but only for several seconds a couple of miles into the first run of the day.

 

To check for air getting into my fuel I'm thinking of temporarily exchanging the tandem pump feed line with clear plastic and fixing a camera to record what's flowing on a test drive.

 

As for you, if it is predictable and repeatable, without a log of what's happening it's hard to say with certainty.  There are many factors involved.

7 minutes ago, J.R. said:

Have a scan done with a proper diagnostic tester preferably VCDS or failing that at a garage with a Snap-on or similar one that can interrogate the various modules.

 

The toy testers wont tell you anything except standardised OBDII codes after a MIL light has been illuminated.

I was hoping it might be a common fault and might be able to sort out myself. 
cheers👍🏻

Torsion angle, but again you would need VCDS to know.

13 minutes ago, MicMac said:

Interesting...

 

I have a similar issue but only for several seconds a couple of miles into the first run of the day.

 

To check for air getting into my fuel I'm thinking of temporarily exchanging the tandem pump feed line with clear plastic and fixing a camera to record what's flowing on a test drive.

 

As for you, if it is predictable and repeatable, without a log of what's happening it's hard to say with certainty.  There are many factors involved.

That’s how mine started about a year ago. It was very intermittent. It cruises fine it is just under high gear acceleration in fifth or sixth gear, fourth is almost unnoticeable. I still seam to think it is either airflow sensor related as that would be linked to engine vacuum as well, would it not?

Well thanks for your input guys. It turned out to be a blocked fuel filter as mentioned by MicMac 👍🏻 It’s running great again now. 
 

Thanks 

 

Peter

I have this problem. Had injector changed amd started juddering under boost in 2nd 3rd and so on. Deffo will be getting a new filter tomorrow and trying that 👌🏾