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Help ma Bob! My R is smoking something on start-up

OEMPL+S

Go Kart Newbie
Location
Canadarr
Car(s)
7 R
Hey,

Looking for some help fair humans.

Basically my R is smoking and backfiring on Cold-start .... Cold-start seems to be shorter .... This thing has just started in the past few days.

The smoke it's puffing is of a blue tinge and smells of either oil or petrol ....

I don't know what the heck to do about it .... plugs are new .... Oil change is only 1800km since it was done.

Is it safe to continue driving and starting it up this way?
I wanna take it in as soon as possible but I want to have some idea if others have had the same issue ....

It's never had a carbon cleaning ....
Or a PCV change ....

But has anyone else had loud irregular backfires and smoking for a minute on cold-start? .... Car sounds almost like it's gonna stall and it smokes in a sad way.

Appreciate responses
 

jmblur

Autocross Champion
Location
Massachusetts
Car(s)
2017 Golf R
Definitely not normal. Blue smoke is oil. Valve stem seals are most likely culprit by far, followed by PCV. You've probably fouled plugs by this point which isn't helping, and could cause the backfire until the plug gets warm enough to burn off oil residue, but you can pull plugs to see if there's an obvious bad cylinder. Pulling codes is obvious first step, I'd expect misfire codes on the cylinder with a bad seat.

Backfiring will kill your cat fast, and could cause other damage. I wouldn't drive it until fixed.

PCV is relatively easy and cheap to replace (with plugs, since you're 3/4 of the way there anyway) but my money is on valve stem seals, a bad PCV would likely cause other issues.
 

OEMPL+S

Go Kart Newbie
Location
Canadarr
Car(s)
7 R
Definitely not normal. Blue smoke is oil. Valve stem seals are most likely culprit by far, followed by PCV. You've probably fouled plugs by this point which isn't helping, and could cause the backfire until the plug gets warm enough to burn off oil residue, but you can pull plugs to see if there's an obvious bad cylinder. Pulling codes is obvious first step, I'd expect misfire codes on the cylinder with a bad seat.

Backfiring will kill your cat fast, and could cause other damage. I wouldn't drive it until fixed.

PCV is relatively easy and cheap to replace (with plugs, since you're 3/4 of the way there anyway) but my money is on valve stem seals, a bad PCV would likely cause other issues.

So it's likely valve stem seals?

Would It mean I can't drive it 25km to the dealer?

It doesn't smoke well driving it at all.

Should I just tell them to pick it up with a tow truck?
 

jmblur

Autocross Champion
Location
Massachusetts
Car(s)
2017 Golf R
Can you pull codes? That would give a lot more info, but blue smoke on startup is a pretty typical symptom of valve stem seal failure.

One more start probably won't kill it, but the backfiring is concerning. I'd wait for another opinion on here for just how concerning!
 

OEMPL+S

Go Kart Newbie
Location
Canadarr
Car(s)
7 R
Can you pull codes? That would give a lot more info, but blue smoke on startup is a pretty typical symptom of valve stem seal failure.

One more start probably won't kill it, but the backfiring is concerning. I'd wait for another opinion on here for just how concerning!

Tried pulling codes .... No codes of any sort. This is through OBD MX - Torque lite, .... Also no CEL on the dash, at all today

The backfires are just a bit louder than normal coldstart backfires .... Just like a louder missfire, but stuttering missfires that are frequent, unlike the normal quite little pops and missfires of a cold start.
Sorry I may have given the impression that there really loud .... There definitely not quiet. like my dad heard them and he's sorta numb to noise usually. It's just there a fair bit louder than the usual cold-start missfires.

Thanks for the help so far
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
So it's likely valve stem seals?

Would It mean I can't drive it 25km to the dealer?

It doesn't smoke well driving it at all.

Should I just tell them to pick it up with a tow truck?
You can drive it to the dealer safely.
 

OEMPL+S

Go Kart Newbie
Location
Canadarr
Car(s)
7 R
Get something that can count misfires.
My ear. I'm gonna say 10-12 ish .... And there sorta rolling like it's gonna stall almost and the cold-start is shorter than usual it seems.
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
Definitely not normal. Blue smoke is oil. Valve stem seals are most likely culprit by far, followed by PCV. You've probably fouled plugs by this point which isn't helping, and could cause the backfire until the plug gets warm enough to burn off oil residue, but you can pull plugs to see if there's an obvious bad cylinder. Pulling codes is obvious first step, I'd expect misfire codes on the cylinder with a bad seat.

Backfiring will kill your cat fast, and could cause other damage. I wouldn't drive it until fixed.

PCV is relatively easy and cheap to replace (with plugs, since you're 3/4 of the way there anyway) but my money is on valve stem seals, a bad PCV would likely cause other issues.
What you said is true but the OP made it sound like this just instantly started.
 

OEMPL+S

Go Kart Newbie
Location
Canadarr
Car(s)
7 R
You can drive it to the dealer safely.

Okay thank you. Helps to have that assurance .... I'm still on the stock downpipe so it's got two cats and I don't wanna havta be replacing that when the warranty is run out.
 

jmblur

Autocross Champion
Location
Massachusetts
Car(s)
2017 Golf R
Tried pulling codes .... No codes of any sort. This is through OBD MX - Torque lite, .... Also no CEL on the dash, at all today

The backfires are just a bit louder than normal coldstart backfires .... Just like a louder missfire, but stuttering missfires that are frequent, unlike the normal quite little pops and missfires of a cold start.
Sorry I may have given the impression that there really loud .... There definitely not quiet. like my dad heard them and he's sorta numb to noise usually. It's just there a fair bit louder than the usual cold-start missfires.

Thanks for the help so far
Ok, I was picturing gunshots. Should be fine to drive to the dealer, I wouldn't get too deep into boost though.
 

OEMPL+S

Go Kart Newbie
Location
Canadarr
Car(s)
7 R
What you said is true but the OP made it sound like this just instantly started.

Yes It just instantly started .... No sign of smoke on start up before today .... Although I think I may have heard the weird noises (louder stuttering missfires) maybe yesterday.
 

OEMPL+S

Go Kart Newbie
Location
Canadarr
Car(s)
7 R
Ok, I was picturing gunshots. Should be fine to drive to the dealer, I wouldn't get too deep into boost though.

No sorry, my skill at writing the initial post may have been lacking ....
If it was doing that I definitely wouldn't even start it.

Okay I'll drive it chill.

I appreciate the help
 

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
Yes It just instantly started .... No sign of smoke on start up before today .... Although I think I may have heard the weird noises (louder stuttering missfires) maybe yesterday.
Just get it to the dealer if it doesn't smoke and runs okay after it's warmed up. And definitely no CEL?
 
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