1.0TSI Normal idle rpm when engine is cold?

[steslatt]

Whats the normal idle rpm when engine is cold? I feel like mine runs high sometimes at about 1200rpm until I've done a couple of minutes driving then it settles down.  

[Ootohere]

@steslatt

?

What if you start it and do not drive off but keep the engine running, how long until the RPM drops?

?

Do you have a 1.0TSI with or without a GPF,

and a manual or a DSG?

[steslatt]

I'm not sure, i usually just drive off. I'll have to test it out. 

Not sure on the GPF? It's a manual.

[Ootohere]

When was your car built?   With a GPF might behave differently from without.

[steslatt]

1 minute ago, Roottootemblowinootsoot said:

When was your car built?   With a GPF might behave differently from without.

2017

[Ootohere]

OK, so no GPF, 

but your car is remapped.

[steslatt]

Yeah it's been remapped but I've only recently noticed it doing this, like since its gotten warmer.

[Ootohere]

Are you starting the car with AC on or on Auto?, and have you are have you tried it with it off

[steslatt]

7 minutes ago, Roottootemblowinootsoot said:

Are you starting the car with AC on or on Auto?, and have you are have you tried it with it off

AC and fan are both off.

[Ootohere]

Hopefully someone with a 2017 1.0TSI will be along saying how theirs acts.

 

In my experience of 1.0TSI with a DSG it takes about 40 seconds to drop from around 1,100 rpm to 800-850 when sitting after starting.

[steslatt]

So after a bit more testing it only seems to happen when I've been out in the car then its been left for a few hours. Stone cold in the morning is just normal behaviour of 1100rpm for a minute or so then back down. 

I've noticed that when its up at 1200rpm its also drawing air in when revving it in neutral, like its under load. I can hear the induction roar which it doesn't do when the idle drops after a minute or so.

[ettlz]

All sounds normal. Stone cold, it'll idle 1200-1400 rpm for the first minute or so (apparently some sort of calibration process, or maybe it's trying to expedite oil distribution). Then, or if started hot, it'll settle to 900-1000 rpm.

 

(VW ECUs have done this 'cold high initial idle' thing for years, and in my experience they tend to do it more in warm weather. Years ago I had an Ibiza that, if it had been left in the sun all day, I could get up to 35 mph with no gas pedal, just gear shifting.)

[steslatt]

Ah fair enough if it's normal behaviour. I've just never noticed it before. Thought it could be down to warmer weather coupled with the remap and/or induction kit.

[FabiaGonzales]

Similar behaviour on the 1.2TSI, initially it'll idle high 1100 ish rpm, sometimes higher, sometimes lower, for 30s to a minute ish, in warm weather a cold start it feels like it's holding the wastegate open for a while (my dad commented saying it sounded like there was a hole in the exhaust lol),

While it's doing that it'll be quite sluggish to respond to throttle inputs but is still drivable, usually get to about 10mph in 1st suddenly the ECU goes back to normal mode and the wastegate shuts and boost hits and it's like i've just been rear ended even though im barely pressing the noise pedal!

 

What's the idle rpm like on the 1.0TSI when it's warmed up with/without AC? I had a 1.0TSI monte with dsg for a day and it never dropped below 950rpm idle. It felt alot smoother at idle than my 1.2TSI though, which seems to vary anywhere between 650 and 900rpm depending on how it feels at that moment in time.

Turning on the AC i'd expect it would kick up higher to compensate but no it still sits at 650 and shakes the car like a diesel with solid engine mounts (ok it's not THAT bad but its quite annoying, especially when sometimes it does boost rpms to 850-900 and it makes it much smoother and quieter).

[steslatt]

3 minutes ago, FabiaGonzales said:

Similar behaviour on the 1.2TSI, initially it'll idle high 1100 ish rpm, sometimes higher, sometimes lower, for 30s to a minute ish, in warm weather a cold start it feels like it's holding the wastegate open for a while (my dad commented saying it sounded like there was a hole in the exhaust lol),

While it's doing that it'll be quite sluggish to respond to throttle inputs but is still drivable, usually get to about 10mph in 1st suddenly the ECU goes back to normal mode and the wastegate shuts and boost hits and it's like i've just been rear ended even though im barely pressing the noise pedal!

 

What's the idle rpm like on the 1.0TSI when it's warmed up with/without AC? I had a 1.0TSI monte with dsg for a day and it never dropped below 950rpm idle. It felt alot smoother at idle than my 1.2TSI though, which seems to vary anywhere between 650 and 900rpm depending on how it feels at that moment in time.

Turning on the AC i'd expect it would kick up higher to compensate but no it still sits at 650 and shakes the car like a diesel with solid engine mounts (ok it's not THAT bad but its quite annoying, especially when sometimes it does boost rpms to 850-900 and it makes it much smoother and quieter).

What you have described is exactly how mine is. When I go to drive it within the first 30 seconds or so it drives like a dog and then all of sudden it's fine, boost kicks in as it should. From the times it's happening it seems like it only does it in a certain temperature range. So stone cold is fine and warmed up is fine but if I've drove it then left it for a few hours it does it.

 

When the car is warm it sits at 950rpm and doesn't ever fluctuate. 

[FabiaGonzales]

1 hour ago, steslatt said:

What you have described is exactly how mine is. When I go to drive it within the first 30 seconds or so it drives like a dog and then all of sudden it's fine, boost kicks in as it should. From the times it's happening it seems like it only does it in a certain temperature range. So stone cold is fine and warmed up is fine but if I've drove it then left it for a few hours it does it.

 

When the car is warm it sits at 950rpm and doesn't ever fluctuate. 

 

I wonder why they made the 1.0TSI idle so consistently but let the 1.2TSI do it's own thing idling anywhere between 650 and 900 rpm depending on the current star alignment. I'll see if i can have that altered when i get the turbo mapped in.

[ettlz]

Yep, a warm 1.0 TSI idles at just under 1000rpm, 1100rpm if the clutch pedal is lifted to before the biting point with no gas pedal input. If you tap the gas pedal while slow-manoeuvring using just the clutch, it'll hold the revs at about 1400rpm without further gas pedal input (which is quite useful for parking). Possible reasons for idling higher than the 1.2 could include: Smoothness because it's a 3-cylinder engine? Reducing turbo lag because of its smaller displacement? General usability improvements? Some emissions fudge for direct injection?

Edited 19 June, 2020 by ettlz