Only during cold weather, engine startup dies or rough idle

[cornflakes2]

This only happens during cold weather season or if the car has been parked overnight.
Upon startup, the engine sounds like it has a hard time staying alive, and will begin to sputter out unless I give it some
gas and keep giving it gas until it has warmed up after 1 minute.

It seems to be getting worse each winter as this morning it wasn't even that cold at 11 degrees celsius but the engine
died right after startup. I have to give it more gas than I usually did last year and the year before that.

Once the engine has been on for a minute, no problems. After driving and parking, I can restart the car without any issues
as I assume it's because the engine is still warm. This only happens when I have left the car parked for at least 7 or 8 hours or longer.

I have VCDS, so if anyone can recommend what settings I should log and look at to find out what might be causing the issue in cold
weather, I can run a few tests.

Some possibilities from my search online:

-idle air control motor that's slow when cold
-temp sensor (either for coolant or for ECM), or wiring
-RFD (runner flap delete)....I believe the runner flaps have been deleted/removed from the intake manifold (by previous owner)
and read that could be causing cold start issues with it deleted.

2013 VW Scirocco R, 2.0 L TFSI (EA113 engine), Automatic, 67k km, gasoline (high octane 94 i think), new spark plugs, ignition coils,
fuel filter, oil change (at regular intervals).

Edited by cornflakes2 on Saturday 30th November 08:09

[Belle427]

The coolant temp sensor is the first thing I’d change, it’s a very common part to fail on vag cars.

[Tyre Smoke]

Belle427 said:

The coolant temp sensor is the first thing I’d change, it’s a very common part to fail on vag cars.

Yep, sounds like some part of the cold start isn't functioning. You're effectively trying to start a cold motor without any 'choke'. The car thinks it's a hot engine, when it obviously isn't.

[cornflakes2]

Thanks for the replies. I will just try and see what I can find using my VCDS but I'm not familiar with how to read the data. I'm going to have to ask someone with expertise/experience or post the data and see if I can find out exactly what is causing the cold start issue.

I'm still thinking about the RFD. APR(stage kit) website says if the car was tuned and has RFD, it's famous for having cold start issues but a free recalibration of the ECU would be serviced to resolve the cold start issue. But it seems that since its getting worse each year (3rd winter now that I've had this car), it sounds more like a part that is getting worse/failing rather than just a ECU tuning adjustment.

[cornflakes2]

01 - Engine - Status: Malfunction 0010

Got this fault code:

1 Fault Found:
001286 - Idle Control System
P0506 - 002 - RPM Lower than Expected - Intermittent
Freeze Frame:
Fault Status: 00100010
Fault Priority: 2
Fault Frequency: 1
Reset counter: 255
Mileage: 66223 km
Time Indication: 0
Date: 2014.02.27
Time: 00:07:44

Freeze Frame:
RPM: 747 /min
Load: 29.0 %
Speed: 0.0 km/h
Temperature: 18.0°C
Temperature: 18.0°C
Absolute Pres.: 1010.0 mbar
Voltage: 14.224 V


I'm not sure if this tells anything specific, but a simple google search said:

A P0506 DTC trouble code may be caused by one or more of the following: A vacuum leak An air restriction in the intake air path or exhuast A faulty positive crankcase ventilation (PCV) valve Damaged/failed/dirty throttle body Internal engine problem Failed PCM


Any suggestions?

[annodomini2]

Is your clock set correctly? As that fault is from 2014.

[cornflakes2]

nope, I don't know where the clock setting is. I've noticed the dates on all my logs as well but i don't know if that is the car's date or my laptop's or the program.

[Tyre Smoke]

Start off by giving your throttle body a good clean. It might be as simple as that.

[cornflakes2]

Tyre Smoke said:

Start off by giving your throttle body a good clean. It might be as simple as that.

Thanks for the reply. I think the TB is the least likely issue because it was thoroughly cleaned in 2018 at the garage. Even when the mechanic at that time checked it out, he said it was really clean.

Does that fault code not tell anything specific? Is it one of those fault codes that could mean half a dozen reasons why it came up? Hate those cuz it doesn't really help and tell you what the issue is other than saying, "there's something wrong with the car".

[Tony427]

Sounds like really small vacuum leak to me. Chekc every vacuum tube off the plenum for cracks or splits.
.

[cornflakes2]

Tony427 said:

Sounds like really small vacuum leak to me. Chekc every vacuum tube off the plenum for cracks or splits.
.

Thanks for the reply