Notices
991 Turbo 2012-2019 Turbo and Turbo S

Misfire Detected

Thread Tools
 
Search this Thread
 
Old Aug 4, 2020 | 09:07 AM
  #16  
dbhajek's Avatar
dbhajek
Thread Starter
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 297
Likes: 104
From: San Antonio, TX
Default

Originally Posted by bleedingedge
At least for the 997.2 as per workshop manual it is 7.5 ft lbs.
EDIT: Same for 991 as per Workshop manual. 7.5 ft lbs or 10 Nm
Thanks, don't think I even have a torque wrench that goes down that low
Reply
Old Aug 4, 2020 | 09:14 AM
  #17  
bleedingedge's Avatar
bleedingedge
Advanced
 
Joined: May 2020
Posts: 67
Likes: 21
Default

Originally Posted by dbhajek
Thanks, don't think I even have a torque wrench that goes down that low
Xmas is coming soon :-)
Reply
Old Aug 4, 2020 | 11:19 AM
  #18  
2fcknfst's Avatar
2fcknfst
RL Community Team
Rennlist Member
5 Year Member
 
Joined: Mar 2018
Posts: 23,637
Likes: 5,524
From: Vancouver
Default

It is either a coil, a plug or you have a vacuum leak somewhere on the intake - I just went through this on my 996 and it turned out that I had split an intercooler - gave me the same codes and ran terribly.

It is becoming very apparent to me, that these cars do not like vacuum leaks and these leaks can cause other seemingly unrelated codes to appear.
Reply
Old Aug 4, 2020 | 11:58 AM
  #19  
dbhajek's Avatar
dbhajek
Thread Starter
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 297
Likes: 104
From: San Antonio, TX
Default

Originally Posted by 2fcknfst
It is either a coil, a plug or you have a vacuum leak somewhere on the intake - I just went through this on my 996 and it turned out that I had split an intercooler - gave me the same codes and ran terribly.

It is becoming very apparent to me, that these cars do not like vacuum leaks and these leaks can cause other seemingly unrelated codes to appear.
It's going to be a bummer if after changing plugs and coils its a vacuum leak. You split an intercooler or intercooler hose?


Reply
Old Aug 4, 2020 | 12:01 PM
  #20  
2fcknfst's Avatar
2fcknfst
RL Community Team
Rennlist Member
5 Year Member
 
Joined: Mar 2018
Posts: 23,637
Likes: 5,524
From: Vancouver
Default

Well, at least you have it apart...

You should be able to change the coils/plugs and then do a pressure test and listen for leaks - no leaks detected, put 'er back together and enjoy. I was thinking that it wasn't apart, this will make it much easier to check.
Reply
Old Aug 4, 2020 | 12:23 PM
  #21  
dbhajek's Avatar
dbhajek
Thread Starter
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 297
Likes: 104
From: San Antonio, TX
Default

Originally Posted by 2fcknfst
Well, at least you have it apart...

You should be able to change the coils/plugs and then do a pressure test and listen for leaks - no leaks detected, put 'er back together and enjoy. I was thinking that it wasn't apart, this will make it much easier to check.
On your 996 you were getting a cylinder misfire on the same cylinder with a vacuum leak? Did you split a hose or a hole intercooler?
Reply
Old Aug 4, 2020 | 12:34 PM
  #22  
2fcknfst's Avatar
2fcknfst
RL Community Team
Rennlist Member
5 Year Member
 
Joined: Mar 2018
Posts: 23,637
Likes: 5,524
From: Vancouver
Default

On my 996 I actually split an intercooler core, which made it incredibly hard to trace. My visual inspections showed nothing wrong, everything was connected. It wasn't until I disconnected the output side of the turbo and put about 20psi into the closed circuit could I identify the problem with the intercooler. One of the issues was that the misfire was seemingly random - it moved from cylinder to cylinder and it went away (completely) when you drove it - only at idle did it sound horrible and throw codes. It also had an interesting side effect - at about 2k rpm it would in fact hold the car at a constant speed like a for of cruise control - I suppose that was the natural 'balance' between the throttle body and the split in the IC.
Reply
Old Aug 4, 2020 | 01:18 PM
  #23  
dbhajek's Avatar
dbhajek
Thread Starter
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 297
Likes: 104
From: San Antonio, TX
Default

Originally Posted by bleedingedge
Xmas is coming soon :-)
Harbor Freight here I come.
Reply
Rennlist Stories

The Best Porsche Posts for Porsche Enthusiasts

story-0

Theon Goes Full Carbon Fiber With Stunning New Build

 Verdad Gallardo
story-1

Six Genius Porsche-Themed Gifts That'll Make Any Dad or Grad Smile

 Joe Kucinski
story-2

10 Used Porsches Are Selling for Way Too Cheap

 Joe Kucinski
story-3

Tuner Is Converting Porsche 911s Into Shooting Brakes

 Verdad Gallardo
story-4

This Coachbuilt Creation Is A Modern Take on the Legendary Porsche 917

 Verdad Gallardo
story-5

Is This Convertible Cayenne A Steal, Or A Returnless Investment?

 Verdad Gallardo
story-6

10 Best Non-Flat Six Porsches You Can Buy For Under $100K

 Joe Kucinski
story-7

Porsche's Top 5 Most Questionable Naming Decisions

 Verdad Gallardo
story-8

Pogea Racing's 964 Porsche 911 Reimagination Stands Out in a Crowded Field

 Verdad Gallardo
story-9

6 Convertible Top MYTHS Most People Don't Understand!

 Michael S. Palmer
Old Aug 8, 2020 | 08:10 PM
  #24  
dbhajek's Avatar
dbhajek
Thread Starter
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 297
Likes: 104
From: San Antonio, TX
Default

Update, new plugs and coils are in and so far no miss fires. I think if I had to do it again I could knock it out in one day. Number one and four cylinders are the hard ones to get too.
Reply
Old Aug 29, 2020 | 06:14 PM
  #25  
pfbz's Avatar
pfbz
Rennlist Member
10 Year Member
 
Joined: Jul 2012
Posts: 7,929
Likes: 3,147
From: US
Default

DUPLICATE

Last edited by pfbz; Aug 29, 2020 at 06:23 PM.
Reply
Old Aug 29, 2020 | 06:20 PM
  #26  
pfbz's Avatar
pfbz
Rennlist Member
10 Year Member
 
Joined: Jul 2012
Posts: 7,929
Likes: 3,147
From: US
Default

I just picked up a misfire code as well... Car went into limp mode, lit up all the warnings (First engine fault, then PSM, PDCC, 4-wheel drive, all "drive on carefully"). Off/lock/wait/restart didn't clear codes.

After Dealer says problem with coil pack. Full 60K service was done less than 3K miles ago with new plugs, but presumably didn't put in new coil packs (stupid. It was before I owned the car, dealer prepping it for CPO which it has).
Codes where:
P0301 (Cyl. 1 Misfire)
P2302 (Bar ignition module on cyl 1, soft shutdown).
(and a course a bunch of others, but I think these are the relevant ones)

Also waiting to hear if coil packs are "wear and tear items as defined by PCNA". Kind of sucks, the coil packs themselves are not that expensive, but dismantling the rear of the car for access, which THEY JUST DID for the 60K service, is quite a few book hours. There is no "scheduled maintenance" replacement for the coil packs.

After dealer pulled codes, they said they were going to reset them, but when I got back in the car the codes were still present. So either they reset the codes and they reoccured almost instantly or (my theory) they didn't actually reset them even though the service writer said they did. I

I reset them myself when I got home, and so far, at least on a short test drive, they have not reoccurred.

Sigh... This is why I do most work on my cars myself.






Has anyone ever seen an official list of "Wear and tear items defined by PCNA "? Sure, brakes, tires, wiper blades, clutches and spark plugs are obvious "wear and tear" items. I personally wouldn't consider coil packs to be "wear and tear", and they are not a "scheduled maintenance" item, and IMHO a coil pack failure under original or CPO warranty *should* be covered. Service manager wasn't in, so I won't hear more until Monday.







Last edited by pfbz; Aug 29, 2020 at 06:30 PM.
Reply
Old Aug 29, 2020 | 06:32 PM
  #27  
dbhajek's Avatar
dbhajek
Thread Starter
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 297
Likes: 104
From: San Antonio, TX
Default

Originally Posted by pfbz
I just picked up a misfire code as well... Car went into limp mode, lit up all the warnings (First engine fault, then PSM, PDCC, 4-wheel drive, all "drive on carefully"). Off/lock/wait/restart didn't clear codes.


Codes where:
P0301 (Cyl. 1 Misfire)
P2302 (Bar ignition module on cyl 1, soft shutdown).
(and a course a bunch of others, but I think these are the relevant ones)

Dealer says problem with coil pack. Full 60K service was done less than 3K miles ago with new plugs, but presumably didn't put in new coil packs (stupid. It was before I owned the car, dealer prepping it for CPO which it has).

Also waiting to hear if coil packs are "wear and tear items as defined by PCNA". Kind of sucks, the coil packs themselves are not that expensive, but dismantling the rear of the car for access, which THEY JUST DID for the 60K service, is quite a few book hours.

After dealer pulled codes, they said they were going to reset them, but when I got back in the car the codes were still present. So either they reset the codes and they reoccured almost instantly or (my theory) they didn't actually reset them even though the service writer said they did. I

I reset them myself when I got home, and so far, at least on a short test drive, they have not reoccurred.

Sigh... This is why I do most work on my cars myself.
Mine was cylinder 4. I saw some where that dropping the motor is what it calls for, I could see it make it a little easier. I don't know how involved dropping the motor a couple of inches is though.

The hard part for me was the heat in San Antonio while working on it.

Reply
Old Aug 29, 2020 | 06:39 PM
  #28  
pfbz's Avatar
pfbz
Rennlist Member
10 Year Member
 
Joined: Jul 2012
Posts: 7,929
Likes: 3,147
From: US
Default

I've done coils and plugs on a 996 Turbo several times... Quite a bit of work, but not terribly difficult. Sounds like the 991 Turbo is very similar, but perhaps just a bit more difficult.

But I will be more than a little irritated if it is not covered under my CPO, especially since they just did a full/major service ~3K miles ago.
Reply
Old Aug 29, 2020 | 07:36 PM
  #29  
dbhajek's Avatar
dbhajek
Thread Starter
Rennlist Member
15 Year Member
 
Joined: Sep 2010
Posts: 297
Likes: 104
From: San Antonio, TX
Default

Originally Posted by pfbz
I've done coils and plugs on a 996 Turbo several times... Quite a bit of work, but not terribly difficult. Sounds like the 991 Turbo is very similar, but perhaps just a bit more difficult.

But I will be more than a little irritated if it is not covered under my CPO, especially since they just did a full/major service ~3K miles ago.
its been a long time since I had my 996 Turbo, but I remember it to be way easier.
Reply




All times are GMT -3. The time now is 04:34 AM.

story-0
Theon Goes Full Carbon Fiber With Stunning New Build

Slideshow: Built around a carbon-bodied 964 and a naturally aspirated 4.0-liter flat-six, this bespoke commission highlights how far the restomod formula has evolved.

By Verdad Gallardo | 2026-06-06 14:41:46


VIEW MORE
story-1
Six Genius Porsche-Themed Gifts That'll Make Any Dad or Grad Smile

Slideshow: Six genius gifts that'll make any Dad smile.

By Joe Kucinski | 2026-06-04 04:58:13


VIEW MORE
story-2
10 Used Porsches Are Selling for Way Too Cheap

Slideshow: These 10 used Porsches offer more driving thrills than their price would suggest.

By Joe Kucinski | 2026-06-03 09:11:13


VIEW MORE
story-3
Tuner Is Converting Porsche 911s Into Shooting Brakes

Slideshow: A Polish Porsche specialist is moving ahead with one of the most unusual 911 conversions in recent memory: a shooting brake version of the 991-generation sports car.

By Verdad Gallardo | 2026-06-01 19:46:47


VIEW MORE
story-4
This Coachbuilt Creation Is A Modern Take on the Legendary Porsche 917

Slideshow: A Porsche Carrera GT has been transformed into a one-off coachbuilt machine that blends analog supercar engineering with styling inspired by the legendary 917 race cars.

By Verdad Gallardo | 2026-06-01 17:06:04


VIEW MORE
story-5
Is This Convertible Cayenne A Steal, Or A Returnless Investment?

Slideshow: A heavily modified Porsche Cayenne convertible with faux wood trim and a long list of flaws recently sold at auction for surprisingly little money.

By Verdad Gallardo | 2026-05-29 18:52:37


VIEW MORE
story-6
10 Best Non-Flat Six Porsches You Can Buy For Under $100K

Slideshow: If you have $100K to spend on a Porsche but want something a little different, these are the 10 best non-flat six Porsches you can buy.

By Joe Kucinski | 2026-05-28 15:36:11


VIEW MORE
story-7
Porsche's Top 5 Most Questionable Naming Decisions

Slideshow: For a company obsessed with engineering precision, Porsche has occasionally named its cars in ways that left even loyal enthusiasts scratching their heads.

By Verdad Gallardo | 2026-05-27 18:43:48


VIEW MORE
story-8
Pogea Racing's 964 Porsche 911 Reimagination Stands Out in a Crowded Field

Slideshow: Pogea Racing's latest Porsche 964 project blends carbon-fiber construction, modern chassis upgrades, and up to 500 horsepower while keeping the air-cooled 911 experience firmly analog.

By Verdad Gallardo | 2026-05-23 10:34:27


VIEW MORE
story-9
6 Convertible Top MYTHS Most People Don't Understand!

Slideshow: dispelling common convertible top myths

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE