Diesel ticking over high...!!

vectra

I asked this exact question over on vagdrivers.net.
48 views and not one reply
Doesnt say much for their knowledge of VAG cars :rolleyes:

Let see how we get on here

Hey guys,
My 08 Cordoba 1.4 tdi Sport at times ticks over at around 1200/1300 revs for a while..
17 thou kilometers on the clock
Mostly stop start driving but when on the open road it gets a good clearing

Anything to look out for?
hoping to change it this year so dont want anything happening it now.

GTE

vectra wrote: »

I asked this exact question over on vagdrivers.net.
48 views and not one reply
Doesnt say much for their knowledge of VAG cars :rolleyes:

I hope you dont have that attitude over here too.

It could be a temperature gauge fooling the ECU into thinking its colder then it is however your engine being as new as it is I would have thought the problem sensor would have been totally out of production. The problem ones were around 2000 and 2003ish.

Maybe its a faulty one.
How is you cold starting?

vectra

Sitec wrote: »

Is it when the vehicle is started or coming into it randomly?

When I start it but not every start.

bbk wrote: »

I hope you dont have that attitude over here too.

Hey,
Enough of that guff now

No,
Honestly though
VAG Forum full of internet genius's not having a clue

bbk wrote: »

It could be a temperature gauge fooling the ECU into thinking its colder then it is however your engine being as new as it is I would have thought the problem sensor would have been totally out of production. The problem ones were around 2000 and 2003ish.

Maybe its a faulty one.
How is you cold starting?

As above.
When I start it mainly
When cold.?
Not certain if i can answer that one properly,
I could start it from cold and drive from my house to the local Super Valu pick up what I need and drive home again.
Possible 2.5 mile round trip.
Leave the car fro may an hour and start it to go out again and it could again do it at that point.
Settles down again after a short while

Is it some "filter" regenerating itself maybe as I do a lot of stop start driving?

GTE

vectra wrote: »

When I start it but not every start.




Hey,
Enough of that guff now

No,
Honestly though
VAG Forum full of internet genius's not having a clue



As above.
When I start it mainly
When cold.?
Not certain if i can answer that one properly,
I could start it from cold and drive from my house to the local Super Valu pick up what I need and drive home again.
Possible 2.5 mile round trip.
Leave the car fro may an hour and start it to go out again and it could again do it at that point.
Settles down again after a short while

Is it some "filter" regenerating itself maybe as I do a lot of stop start driving?

A good sign of a bad temp gauge is when you start up in the cold the glow plugs dont come on at all or for long enough and make it difficult to start. As well as irregular idle speeds.

Im not too familiar with newer TDI's but you may have struck on something with the filter. I believe they are called diesel particulate filters.

If they clog I have read of it causing problems. They need a good thrashing once in a while. I have read many times that TDI's for a couple of reasons should be treated with a heavy foot from time to time. For my engine and Id say for yours too there is something called the exhaust recirculation valve which as you can imagine has summet to do with the exhaust. They can clog if you do stop starts a lot. The remedy of that is basically to drive the car hard for a while so it can burn the build up of exhaust. I believe the DPF can be fixed with the same principle.

If the DPF is the problem you need a good stretch at full operation temp so the filter can regenerate.

Decent motorway drive.

If that is it its not a problem with the car, its just a problem that the driving style doesnt suit the engine. Buried in the small print somewhere no doubt.

vectra

bbk wrote: »

A good sign of a bad temp gauge is when you start up in the cold the glow plugs dont come on at all or for long enough and make it difficult to start. As well as irregular idle speeds.

Decent motorway drive.

If that is it its not a problem with the car, its just a problem that the driving style doesnt suit the engine. Buried in the small print somewhere no doubt.

Thats the one I was thinking of
DPF
I am not sure if my car has one or not.
I am assuming it has

GTE

I have read of a light on the dash which indicates if summet is up with it. That could have been for a Ford though.

There is only one way to troubleshoot it . . . FLOOR IT haha

vectra

bbk wrote: »

There is only one way to troubleshoot it . . . FLOOR IT haha

Trust me..
When I take this thing out on the open road it gets some fright

vectra

Took it on the motorway yesterday and gave it a good run. Still the same.
actually, anytime i start it today it revs away at 1200~1500 rpm.
Took it for a run of about 4-5 miles today in 3rd gear @ 80 odd kmh. = approx 3500rpm
Brought it home. turnmed it off, started it again and it buzzed away at around 1200.

Tigger

i'm goona say check the throttle position sensor
mabey its not making idle

vectra

Tigger wrote: »

i'm goona say check the throttle position sensor
mabey its not making idle

Car is out of warranty since middle of February.
Reported this to the dealer and he said it is only the weather being cold and it is like using a choke.. At the time it seemed possible but not now with the temp after rising in the weather. Maybe I should get back to him

RICARDO1982

75% certain the throttle pedal is the cause of this problem i have seen this twice before
I am not 100% certain it will solve your problem. good luck hope you get it sorted

vectra

RICARDO1982 wrote: »

75% certain the throttle pedal is the cause of this problem i have seen this twice before
I am not 100% certain it will solve your problem. good luck hope you get it sorted

You mean replace the throttle pedal?

positivevibes

First of all the throttle body would need cleaning up with some carb cleaner as they do get clogged up.After that you need someone with the right diagnostic equipment to reset the idle adaptions.while they have the computer hooked up you should get the coolant temperature data checked(but really that needs to be checked when cold and hot).

Slidey

If it was my car I would like to get it on diagnostics and view real time data paying special attention to the throttle pedal values.

Also, if the throttle was showing more than tick over values it would probably store a fault when the brake was pressed at the same time as this should not happen in normal everyday situations

Fishtits

bbk wrote: »

I have read of a light on the dash which indicates if summet is up with it. That could have been for a Ford though.

There is only one way to troubleshoot it . . . FLOOR IT haha

Someone left the door open...

RICARDO1982

Remember lads this is a TDI so it does not have a throttle body to clean or reset..
I have replaced the throttle pedal (it is electrical not a cable ) on very similar cars twice for this problem intermittent high idle. It was not exactly the same car this is why i am not 100%. Anyway no-one can be 100% guessing here . other things to check are breather pipes and inlet manifold for leaks, start basic before running away with mad ideas. Good Luck

vectra

RICARDO1982 wrote: »

Remember lads this is a TDI so it does not have a throttle body to clean or reset..
I have replaced the throttle pedal (it is electrical not a cable ) on very similar cars twice for this problem intermittent high idle. It was not exactly the same car this is why i am not 100%. Anyway no-one can be 100% guessing here . other things to check are breather pipes and inlet manifold for leaks, start basic before running away with mad ideas. Good Luck

Actually i was always complaining about the throttle pedal making a "squeeking" noise. especially when the weather was damp.
and as you describe. It is intermittent.. Running fine with the last couple of days

AzureAuto

Quite, no throttle on diesels, this eliminates 'cleaning out throttles and having them diagnostically reset'.
Accelerator pedal tracks provide a primary input for the fuel injection pulsing. Usually faults in this will flash an EPC or amber engine managment light. Using suitable diagnostic software you can check the track voltage outputs for smooth voltage rises; any jerky or suden voltage jumps would indicate a problem with this pedal unit.
The reason a diesel revs higher is counterwise to a petrol, it indicates an increase in fuel being injected, (as opposed to air). Therefore, checking the sensors that contribute toward the fuelling calculation would be the way to begin. These include coolant temperature sensors, fuel temp sensor, and most importantly the air mass meter.

positivevibes

sorry guys didn't look properly at info.Thought it was petrol:o

GTE

Fishtits wrote: »

Someone left the door open...

Not quite. Apparently the problem with the DPF's is that when driven around the city for a long time the filter cant regenerate, which it does by high exhaust temps resulting from essentially driving one gear lower then you should be for longer.

Same principle for turbos and EGR valves on, at least, the VAG range of TDI's.



Pleasing result of this "maintenance" is some floorage

The pedal calibration makes sense though. Has the car had its battery taken out recently before you had the problem?

I was doing some work on mine and found that I had, well I should have gone through this procedure so the pedal can be calibrated after the battery is taken out.

vectra

bbk wrote: »

Not quite. Apparently the problem with the DPF's is that when driven around the city for a long time the filter cant regenerate, which it does by high exhaust temps resulting from essentially driving one gear lower then you should be for longer.

Same principle for turbos and EGR valves on, at least, the VAG range of TDI's.



Pleasing result of this "maintenance" is some floorage

The pedal calibration makes sense though. Has the car had its battery taken out recently before you had the problem?

I was doing some work on mine and found that I had, well I should have gone through this procedure so the pedal can be calibrated after the battery is taken out.

That looks "Yucky" :eek:

Battery was never out
Gonna ring the dealer tomorow and get it booked in for checking.. I did tell him before the warranty was out and he advised me not to worry about it..
His problem now to do it under warranty,

shamwari

I'd get the car scanned first to read the live data. You could have a TPS fault seen as it is sqeaking, and the data will show the TPS being depressed when you are not near it.

The other one to look at is the output from the coolant temperature sensor. VAG cars are nutorious for dickey CTS sensors on petrols and diesels.

One other remote possibility which I've seen once on an Opel diesel is a faulty vechicle speed sensor in the gearbox. In this case, the sensor was reporting a positive vehicle speed when the car was actually stopped! The ECU increases minimum revs slightly at low speeds to act as an "anti stall" tactic, and thinking the car was moving, it caused the idle speed to fluctuate wildly, with some slight movement of the speedometer itself! It is unlikely that this is your problem because your car should have ABS, and if so it will calculate road speed from the ABS sensors, rather than using a VSS. Again a scan on live data will show road speed, and if you have positive road speed when stopped, I would be looking at the VSS / ABS sensors for a possible cause.

Finally, other possible causes are an excess of oil in the breather / EGR systems. Are these increases in revs accompanied by smoke?