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150GT Passat
09-01-2016, 11:13 PM
Hi guys,

After four Octavias, I bought a 150BHP GT Passat estate just before Christmas, which I'm really pleased with so far.

However, over the last few days, I have noticed that the idle speed is extremely erratic, and even after driving 10 or 20 miles, surely enough to properly warm the engine up, when I stop, it will idle at around 1100 revs or even slightly higher. I've also noticed that the start-stop system wasn't always working. It's been much colder these last few days here, and today, with the temperature at around 2 or 3C, the idle speed always stayed above 1000revs. However, this evening, I went out for a short drive and noticed it seemed to be idling at a much more agreeable 800 revs even after a mile. The temperature had risen to 6.5C.

Has anyone else had these issues, and is it related to the external temperature?

Thanks in advance!

technik
09-01-2016, 11:23 PM
Not had that issue, but the start stop won't work if the engine needs to generate extra power/electricity for the AC, heated seats, de-mister, wing mirrors etc.

By erratic, do you mean the it idles up and down or just that you've noticed the different rev levels at different times?

150GT Passat
09-01-2016, 11:27 PM
Ok, that explains the start-stop bit.
Sorry, perhaps I wasn't clear enough with the idle speed. When starting from cold, it's around 1000revs, then I drive for a while and I'd expect the revs to have reduced to say around 800. But the last few days, if I pull up at a junction, even once the engine is warm, the idle speed hasn't reduced, and in fact has sometimes increased a bit.

technik
09-01-2016, 11:38 PM
Probably worth getting it looked at. Mine idles below 1000 (even when cold I think).

Also, when the start-stop doesn't function, there should be the inactive icon on the dash display ( an A with a line thru it)

150GT Passat
09-01-2016, 11:40 PM
Ok, thanks. I'll keep an eye on it over the next week, and then book it in. And yes, thanks for explaining about the start/stop, there is an A with a line through it when it's not functioning.

150GT Passat
04-02-2016, 05:43 PM
Update, and how ridiculous can this be?

Took my Passat 150Gt Estate in to dealers on Tuesday morning. Got a courtesy car. Phone call Tuesday afternoon from dealer to say that they had put it on the computer and no faults detected. However, they asked if the master technician could take the car home Tuesday night just to check it over and see if anything showed up. I agreed, but was a bit frustrated, as several of my friends have looked at it and agreed that there's definitely something wrong as the idle speed is often above 1000 revs even when fully warmed up.
Wednesday morning- dealer phoned to say master technician agreed there was a problem. Hooray, I thought.
Phoned yesterday evening to see if it's ready to collect- no, still working on it. Fine, I thought, I'll keep the courtesy Golf. Today, Thursday, dealer phones to tell me they can't find a fault with it, computer says all ok. They have another, brand new Passat which they road tested and it displays the same characteristics. So, based on that, there's no problem!
Ha! NO WAY! So, after driving for 33 years, and never having had a car that revs in this way, over 1000 revs when warm, and having done more than 250K miles in the last 12 years in various Octavia 2.0 diesels, and a Seat Exeo, all with broadly similar engines, I'm to put up with this one that revs too high, just because they say another one does it, and even though their master technician admitted it wasn't right!!
ADVICE PLEASE folks?? Can other Passat B8 owners with 2.0 150bhp diesel engines tell me what their engines do please? What should I say to the dealer? I told them today I didn't want the car today, but will come tomorrow to see the other Passat to compare their idle speeds.
HELP!!

150GT Passat
05-02-2016, 07:26 PM
Passat B8 Idling problem - part 1 - YouTube (https://www.youtube.com/watch?v=3eYosLTiSAo) - part 1, only 20 seconds, showing my car's idling after a 27 mile journey today back from the dealer.
Passat B8 Idling problem - part 2 - YouTube (https://www.youtube.com/watch?v=1n7FrlczGvo) - part 2, again 20 seconds, which clearly shows what happens when I restart the car after a ten minute rest. Engine still hot (it's just back from a 27 mile motorway journey) but watch a few seconds in.

Dealer reports that a brand new Passat they have, with 25 miles on the clock, does exactly the same thing, so based on that, there is nothing wrong with mine. Please, tell me I'm not crazy!

technik
05-02-2016, 11:35 PM
Passat B8 Idling problem - part 1 - YouTube (https://www.youtube.com/watch?v=3eYosLTiSAo) - part 1, only 20 seconds, showing my car's idling after a 27 mile journey today back from the dealer.
Passat B8 Idling problem - part 2 - YouTube (https://www.youtube.com/watch?v=1n7FrlczGvo) - part 2, again 20 seconds, which clearly shows what happens when I restart the car after a ten minute rest. Engine still hot (it's just back from a 27 mile motorway journey) but watch a few seconds in.

Dealer reports that a brand new Passat they have, with 25 miles on the clock, does exactly the same thing, so based on that, there is nothing wrong with mine. Please, tell me I'm not crazy!

You're not crazy. That's not right. I'd take it to another dealership.

150GT Passat
06-02-2016, 03:53 PM
Now booked into another dealership for the 16th Feb. Will update afterwards. Thanks.

BenR
15-02-2016, 06:10 PM
Mine idles at 1100 rpm most of the time, hot or cold. At that engine speed there is a little drag on the DSG clutch. Occasionally it drops below 1000 rpm but I can't see any pattern in it. I'm not worried about it; the car is under warranty.

150GT Passat
15-02-2016, 09:52 PM
Mine idles at 1100 rpm most of the time, hot or cold. At that engine speed there is a little drag on the DSG clutch. Occasionally it drops below 1000 rpm but I can't see any pattern in it. I'm not worried about it; the car is under warranty.

Mmm. I'm not sure how to answer that. I've had over 30 cars in my life of driving, and never had one that idles at more than about 750- 800 revs when warmed up. Is it fair to compare a DSG with a manual? (I've never owned an automatic). But I sure as hell want dealer number 2 to come up with an answer tomorrow, as I certainly don't think it's normal, not do I want to put up with it for the next 2 - 3 years.

BenR
16-02-2016, 04:27 PM
Just to add to your frustration... at lunchtime I went out to the car park and sat in the car listening to the radio with the engine running stone cold and it idled at about 750 rpm.

150GT Passat
16-02-2016, 11:12 PM
Just to add to your frustration... at lunchtime I went out to the car park and sat in the car listening to the radio with the engine running stone cold and it idled at about 750 rpm.

May I ask a serious question about that? Did you have the heating or air-con, or both on?
I was told today by the 2nd dealer who inspected the car that the reason for the rise in rpm when idling is because the engine management system detects that it is necessary to increase rpm when the car is idling if there are power sources on that are draining the battery- i.e. the air-con, the heated seats, the heating, lights etc. I was told (I kid you not) that according to VW, if the heating is off and there are no drains on power, the car will idle at the correct speed, i.e. 750 - 800rpm.
Now, I also explained to the technician that I have had 5 previous 2.0TDI Skoda and Seat engines, none of which have done this over a combined mileage of 300,000 miles.
I'm awaiting a written report on today's visit, but to me, can you imagine one of the presenters on BBC's watchdog reading out the response from VW: "the customer was told that the car would idle correctly only if he turned the lights and air-con and heating off"....
This sounds more like something from Lada in the 1980s, not VW in 2016.

I'm regretting my move to VW now, and the spending of more than £20,000 on this car.

technik
17-02-2016, 08:22 AM
I'll do a couple of tests on mine. I'll start it up from cold, then I'll put everything on - seats, max aircon, heated screen, heated mirrors, all the lights etc.

I'll let you know the results, but I'm guessing I know it won't do that!

150GT Passat
17-02-2016, 05:20 PM
I'll do a couple of tests on mine. I'll start it up from cold, then I'll put everything on - seats, max aircon, heated screen, heated mirrors, all the lights etc.

I'll let you know the results, but I'm guessing I know it won't do that!

I'd very much appreciate that. Thanks.

goce.chekorov
17-02-2016, 08:48 PM
could it be forced regen?

150GT Passat
17-02-2016, 10:17 PM
Possibly. It has been mentioned by the 1st dealer. But should that be happening every day and every time I use the car?

150GT Passat
17-02-2016, 10:18 PM
I'll do a couple of tests on mine. I'll start it up from cold, then I'll put everything on - seats, max aircon, heated screen, heated mirrors, all the lights etc.

I'll let you know the results, but I'm guessing I know it won't do that!
I can't see on my phone if my reply was sent to you. Did you get it safely?

goce.chekorov
17-02-2016, 10:19 PM
to be honest, I have never noticed my passat to be in forced regen in the 23 000km that I have covered. It might be me not noticing or it could be the fact that I do regular autobahn trips.
I have a fabia for a city runner.

YawnGumbo
18-02-2016, 02:48 PM
Out of interest, other than being annoying, is this causing any other issues? Are you getting poor mpg or anything as a result?

150GT Passat
18-02-2016, 02:56 PM
Out of interest, other than being annoying, is this causing any other issues? Are you getting poor mpg or anything as a result?
Well, I have to admit that I've been very disappointed with the mpg figures so far.
My last car was a 170bhp Octavia vRS estate, 2013 plate, and I didn't exactly drive it slowly. Its longterm average was always around 47mpg, and on my 16 mile commute to and from work, which is part motorway and part B roads, it always averaged around 43mpg. On longer journeys it often did 54 -55 mpg even when driven quickly.
With the Passat, which is 150bhp, and which i have been driving a bit more sedately, I have never seen more than 40mpg on the commute and it's usually around 37mpg. Over the longer term, which includes longer runs at weekends and in the evenings, it's so far averaging about 42 - 43 mpg. This is disappointing as it's not a performance model. I had expected more. However, just in case everyone reading thinks I just like to moan... I don't. The Passat is a really wonderful car, just being spoiled a bit with this issue. To be honest, I think the mpg is probably related.

150GT Passat
18-02-2016, 03:57 PM
Here's an update a couple of days after my car was in to the 2nd dealer.

Firstly, I found the 2nd dealer very courteous overall on the day. I was late getting the courtesy car back, so I didn't get the chance to speak face to face with the workshop controller, but he spent a good bit of time on the phone before I left to collect my car explaining their findings and what they suspected. I've already listed these above- that he suspected additional load on the ECU (perhaps due to the air-con, heated seats etc being on) was telling the ECU to raise the rpm when idling. Whether or not this is indeed the case, who knows. I had asked for a copy of the printout, something in writing, so I could file it away with all the receipts I keep. He had said he would give me something, (as some sort of code had come up on his computer) but as he was away when I got back to collect the car, I asked for it to be emailed to me the next day. (yesterday)

Yesterday late afternoon, having received nothing, I called the dealer back, and the receptionist told me they were not prepared to give me anything in writing. If I came back in (it's 45 miles away from my home!) they would talk me through things again. I told her I had been promised something, and wanted to have some sort of record of the car's visit, and the findings. Imagine if I wanted to sell the car tomorrow and had to explain to a private buyer why the rpm was raised at idle... They point-blank refused to provide anything and indeed refused even to let me speak again to the workshop controller!!

I find all of that extremely bizarre, and pretty disappointing to be honest.

Anyway, back to the car itself. Since its visit there, I have played about with the heating controls. If I set the climate control at a maximum of 21C, with just one light illuminated on the blower control, things do seem to have improved. If I switch on the heated seats, as long as I don't put the climate control away up beyond 22-23c, things are ok. The car idles at around 800rpm, and the start-stop system seems to be working properly.
However, if I raise the temperature of the climate control beyond 24c, even if the blower is still only on one light illuminated (and with everything else off including lights, heated seats etc), the rpm then won't come below 1000 - 1100, even when the engine is hot. Thinking back, as it's been cold over the past few weeks, I have usually had the temperature of the climate control set above 24c, as I like to be nice and warm.

So, it appears there was some truth in the findings from the workshop controller. If I set the climate control to 21c, all seems ok.

Should I simply now accept this and carry on??

technik
19-02-2016, 12:06 AM
Ok, so did a bit of a test today.
Outside temp 3.5c
Started car and idled at just over 800rpm.
Put everything on. Seats, mirrors, lights, aircon. Everything.
No change to revs.

Drove for a few minutes and second time I had to stop at lights (about 2 miles) the auto stop cut the engine.

When the engine temp was at 90c the car idled at just below 800rpm.
Put everything on again - no change in revs.

P Adams
20-02-2016, 12:52 AM
My 2015 GT 150 manual saloon (cold or hot) idles at 1000rpm with the AC on (temp over 21 deg), blower on one light or full on, heated mirrors on, rear window heater on, standard radio on and both front heated seats on full. When I turn everything off it drops down to just below 800rpm.

150GT Passat
20-02-2016, 05:09 PM
My 2015 GT 150 manual saloon (cold or hot) idles at 1000rpm with the AC on (temp over 21 deg), blower on one light or full on, heated mirrors on, rear window heater on, standard radio on and both front heated seats on full. When I turn everything off it drops down to just below 800rpm.
Thanks for this.

I hope this is my final post about this! As I've been on holiday this week, the last couple of days I have been experimenting with different things.
Like P Adams above, as long as I don't set the air-con above 22 deg, the idle speed is now perfect, just around or under 800rpm. If I slam the heating up beyond that, something is kicking in and telling the car to idle more quickly at 1000rpm or higher.

I'm just relieved to have found an answer to this. When I think back, since I got the car, I've had the heating set higher than 22 deg, as it's been pretty cold overall through the last bit of December and January. I'm not fully sure if it was the trip to the 2nd dealer that sorted things or not, but the car is now running sweetly, and more importantly, the way I wanted it to run from the day I got it.

Thanks for all the suggestions and help from all who have commented, publicly and privately to me. :o

P Adams
20-02-2016, 11:25 PM
Thanks for this.

I hope this is my final post about this! As I've been on holiday this week, the last couple of days I have been experimenting with different things.
Like P Adams above, as long as I don't set the air-con above 22 deg, the idle speed is now perfect, just around or under 800rpm. If I slam the heating up beyond that, something is kicking in and telling the car to idle more quickly at 1000rpm or higher.

I'm just relieved to have found an answer to this. When I think back, since I got the car, I've had the heating set higher than 22 deg, as it's been pretty cold overall through the last bit of December and January. I'm not fully sure if it was the trip to the 2nd dealer that sorted things or not, but the car is now running sweetly, and more importantly, the way I wanted it to run from the day I got it.

Thanks for all the suggestions and help from all who have commented, publicly and privately to me. :o


Good news! After enjoying a brand new B5, used B6 and my wife's new B7 (which she still loves better than my B8!), I think the GT is a lovely car to own and drive. Enjoy :D