VW Golf 1.4 TSI Match High Revs at Start-up

[nnchokshi]

I have owned the above for the last year and have been really impressed with its performance so far - VW has done an amazing job with this engine: quite but really powerful.

However, since I have purhcased this car, I have noticed that every often when I turn the car on after it was parked for few hours (e.g. over night), it revs up quite high (upto 1200 rpm) and the revs remain so forever, until I turn the car off and start again. Thereafter the revs come back to normal.

Initially, this used to happen every 1 in 10 starts, but now it happens pretty much every time, particularly if the car was standing in hot weather.

Has anyone else noticed the same problem? Do you know what causes it? I am worried if this is anything to do with turbo - whether the high revs are sustained due to any damage in the turbo?

I took it to the VW dealer in Gloucester last week, but I was told that there is no fault reported in the memory, so the car is perfectly ok. This can't be true however, as the car is not behaving normally as it should. I doubt that they have enough experience about TSI engines yet, especiall 1.4TSI.

I was also told that I should use "Super Unleaded" instead of "Unleaded" for a TSI engine, because "unleaded" does not provide enough lubrication?! Is this really true? As per VW spec, any fuel starting from Octane 95 (normal unleaded) and above should be fine, so why go for expensive Octane 98?

Thank you in advance for your help,

NNC

[Crasher]

This is normal, it is to bring the catalyst up to operating temperature as fast as possible by a high idle, slightly increased fuelling and a secondary air pump blowing (you can here this whining away under the air filter, sounds a bit like a vacuum cleaner) into the exhaust manifold, this significantly reduces cat light up time. Telling you to use Super unleaded due to increased lubrication is utter ****, it has a higher octane which the engine can make use of to advance the timing to improve performance but yes, it is better to use either Shell V Power or Tesco 99.

[nnchokshi]

Thanks Crasher for your reply. That explains it , but then why would you see high-revs more in climate than in cold conditions, e.g. most mornings these days the car starts perfectly normally, but in the evening when it has been sitting outside in 25degC, it does play almost everytime now at the start.

NNC

[Crasher]

It depends on what strategy the ECU wants to employ. I had a chap in a few weeks back with a brand new Leon with the same engine as you and the same issue. I had it all day and could not get it to do it and then when he came to pick it up it did it whilst we were standing at the car and I could tell what it was doing, explained it to him and he was happy.

[nnchokshi]

That's lot more comforting.

Would you suggest driving off in that condition (i.e. high-revs continuing) or turn the engine off and start again when this happens.

From my experience (only once I have tried - got scared thereafter) if I drive off the revs still remain high and the whinning noise continues until I eventually stop and turn the engine off.

NNC

[Crasher]

Just drive it. The whining noise is the Secondary Air Injection pump and this stops after about 30 to 40 seconds. If you shut it down, you defeat the purpose of it coming on. My Octavia sometimes does this in the morning, the part throttle operation being made a little ragged; you just drive through it until it has done its task.

[lambo28]

Thanks, I also have this scenario. Now I know it isn't a major problem! However, I do smell a really strong petrol smell after start-up. Is this normally?

[Crasher]

Yes, it is supposed to save the planet but forgive me for being a sceptic and thinking all this green ******** is just nice wrapping on stealth taxation.

[nnchokshi]

Thanks Crasher for your replies. I tried it y'day and today to leave it revving high at start, and as you say, it did eventually come down on its own within few secs. Previously I had always thought that this is a problem with the car, so never let it run for more than 5 secs.

I'm sure VW could explain some of this behaviour in the car manual or to their dealers around...equally, I can't blame the dealers either because they would not have seen many of the TSI engines yet with any problems!

[Crasher]

I don’t know if it is in the manual but they should be aware of this and explain it to people. It is like the issue over the grade of fuel to use, they should be run on 98RON as a minimum but they never tell people even though it is shown inside the petrol flap.