Hi,

1.9 TDI PD Green Line

Just trying to understand cold engine rpm

Explain

This month (after heavy rain) I start the cold engine in the morning 11 am and start driving, But realised that the cold engine default rpm was 1100 later after 10 -15 min of drive Engine reach normal working temperature and all revs came to normal 850 rpm

It is start happened in this month maybe 2-3 times when the rpm on neutral comes to 1100 rpm

Now Im start watching cold engine rpm in the mornings

Today about 1000 rpm and it is drop like this:

2-5 Min of drive about 1000 rpm engine temperature low

5-10 min of drive about 900-950 rpm engine temperature higher than low

10 – 15 min of drive I’m reaching normal 850 rpm engine temperature normal

So is it something start blocking or some sensors start working incorrectly

It is summer time it is not winter – I can understand that engine needs to warm up but these revs start increasing with the time

As I think before it does not happened (really I do not look this) I mean maybe YES cold engine little increasing rev but it is maybe for couple minutes Now engine to reach 850 rpm takes more longer time. And in this month 1100 revs

Maybe it is normal I do not know as before I do not have diesel

Regards

Inco

Edited

Just Read About EGR valve is it dealer cleaning them on second service ?

Some links

http://www.yell.com/motoring/blog/sluggish-smokey-tdi-it-could-be-your-egr/

http://www.audi-sport.net/vb/a4-a4-cabriolet-s4-forum-b6-chassis/28539-egr-blanking-cap.html

Edited 23 June, 201115 yr by Incognito

Ok, I don't have a Greenwash, but overnight cold start idle rpm with ambiant temp anywhere between -20C and +20C has always been in the range of 850 to 900 rpm.

I do have a greenline superb 1.9 tdi and we haven't had any issues with idling or increased revs in the time that we have owned it. I have noticed that the fluid level in the expansion tank has dropped a fraction, possibly due to evapouration, and there is no evidence of a leak either. It seems to me, that your superb is behaving as it should, and that i would be more worried if it was continually running on a high reading of around 1000 rpm. Just keep fluid's topped up with correct specification like G12 for the engine coolant, and just enjoy the car.

I do have a greenline superb 1.9 tdi and we haven't had any issues with idling or increased revs in the time that we have owned it. I have noticed that the fluid level in the expansion tank has dropped a fraction, possibly due to evapouration, and there is no evidence of a leak either. It seems to me, that your superb is behaving as it should, and that i would be more worried if it was continually running on a high reading of around 1000 rpm. Just keep fluid's topped up with correct specification like G12 for the engine coolant, and just enjoy the car.

I spoke with other person and he have none turbo 1.9 TDI. He told that never ever have any increased idling.

So question why is my car do like this. ?

It symptom that something do not want work correctly.

I know it is can be lot of things

Is it dealer can check data or logs from the car CPU ? or is it can be tested some way

As for my old petrol car experience most idling problems can be related to none working lambda sensors or air sensors When fuel and air mix incorrect. But this can be seen by MPG straight away - because it is increased maybe 40 Percent fuel usage

I spoke with other person and he have none turbo 1.9 TDI. He told that never ever have any increased idling.

So question why is my car do like this. ?

It symptom that something do not want work correctly.

I know it is can be lot of things

Is it dealer can check data or logs from the car CPU ? or is it can be tested some way

As for my old petrol car experience most idling problems can be related to none working lambda sensors or air sensors When fuel and air mix incorrect. But this can be seen by MPG straight away - because it is increased maybe 40 Percent fuel usage

It seems totally normal to me to have high rev idling for the first 10-15 minutes of start-up on a cold engine, if I've read correctly and that's what you're concerned about? If revs drop back to 850-900 after the engine is warm, and remain constant at idle, then it seems all is well

Also, I don't think the other person in your first sentence could have a none turbo 1.9 TDI - the clue's in the T of TDI

It seems totally normal to me to have high rev idling for the first 10-15 minutes of start-up on a cold engine, if I've read correctly and that's what you're concerned about? If revs drop back to 850-900 after the engine is warm, and remain constant at idle, then it seems all is well

Also, I don't think the other person in your first sentence could have a none turbo 1.9 TDI - the clue's in the T of TDI

I agree with you that engine from start-up increasing revs It is normal 900-950 Revs and they drops in couple minutes to 800-850 rpm

But it is happened to me that revs was really to high like 1100 idling and it is happened this month 2-3 times

Are you agree with me that engine CPU do not increasing rev if it is not needed ?

Some component "I do not know" fail / give wrong readings to CPU so this increased fuel to engine

Later after 10-15 min of drive this component start working correctly and engine CPU have right reading and corrected fuel.

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It is feel that temperature or exhaust sensor start playing. As I can not see any other relationships so sensitive to temperature than exhaust sensors

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I do not know is DPF related to this ?

But I know for sure DPF and other exhaust emission lowering equipment will make so much problems in future. Not to my car all these 2.0 TDI CR DPF and other

Les TAX before buy WOW just 35,110 or 0 Pounds - but after warranty finish expensive repair will come 1000 Pounds will just for DPF it self not including mechanic works : )