Make a donation

Author Topic: Spark plug gaps  (Read 49074 times)

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: Spark plug gaps
« Reply #15 on: August 21, 2016, 12:15:12 pm »
Ok, just been trawling local places for the NGKs and got some BKR7EVX. They said they were superseded by the BKR7EIX but are the same. Just bought them, not really thinking.

However, it says PLATINUM on the box. Not... iridium. F*cks sake. Should I be taking them back or will they work?!
They lied mate go  :slap: those mo beeches up.

Offline Namsgti

  • Always Involved
  • ****
  • Thank You
  • -Given: 1
  • -Receive: 2
  • Posts: 84
Re: Spark plug gaps
« Reply #16 on: August 21, 2016, 12:28:18 pm »
After putting thease iridium plugs in my gti I always had problem starting the car in the mornings!!
With the original plugs no problems car started on first turn of key.

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: Spark plug gaps
« Reply #17 on: August 21, 2016, 01:20:40 pm »
I've never had this issue after putting the Iridium IX spark plugs in.

Offline AJP

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 392
  • -Receive: 316
  • Posts: 3212
Re: Spark plug gaps
« Reply #18 on: August 21, 2016, 01:28:30 pm »
Update.

Borrowed my brother's OBD2 thing, expecting to see a cyl 2 misfire code, but... nothing! No codes.

It definitely misfired the day after I fitted the new coils and every day since, the only difference this time is that the engine light flashed but didn't stay illuminated. When I originally had the misfires, before I fitted the coils, the engine light flashed, stayed on, and subsequently I got the cyl 2 misfire code, which I then cleared.

So, to recap, the misfire appears to have subsided and there are no fault codes. I removed the spark plugs, and didn't find anything of concern. They all look similar and they don't look fouled: (1-4 in order from bottom to top; that's just a bit of tubing on plug 1 because the socket wouldn't grab it)



Here's plug 2:



So, back in went the same plugs, this time with 2 and 3 swapped. The plan is to drive it as much as possible to induce the misfire, then scan it, see which cylinder it is.

I've got the new plugs waiting for if and when they're needed.

So I'm a bit stumped for today. The car pulls like a train and is as smooth as it gets. No fault codes. But I know something aint right.
« Last Edit: August 21, 2016, 01:32:51 pm by AJP »

Offline AJP

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 392
  • -Receive: 316
  • Posts: 3212
Re: Spark plug gaps
« Reply #19 on: August 21, 2016, 01:30:07 pm »
Ok, just been trawling local places for the NGKs and got some BKR7EVX. They said they were superseded by the BKR7EIX but are the same. Just bought them, not really thinking.

However, it says PLATINUM on the box. Not... iridium. F*cks sake. Should I be taking them back or will they work?!
They lied mate go  :slap: those mo beeches up.
To be fair they were very good in sorting the proper plugs out on the day, and didn't charge me any extra even though they were more expensive.

Offline AJP

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 392
  • -Receive: 316
  • Posts: 3212
Re: Spark plug gaps
« Reply #20 on: August 21, 2016, 01:39:36 pm »
@maxitrol Is it maybe worth merging this with the thread I linked to in the first post please?

They're both covering the same issue and it'd probably be more helpful to someone reading up on the issue in the future.

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: Spark plug gaps
« Reply #21 on: August 21, 2016, 01:52:26 pm »
Update.

Borrowed my brother's OBD2 thing, expecting to see a cyl 2 misfire code, but... nothing! No codes.

It definitely misfired the day after I fitted the new coils and every day since, the only difference this time is that the engine light flashed but didn't stay illuminated. When I originally had the misfires, before I fitted the coils, the engine light flashed, stayed on, and subsequently I got the cyl 2 misfire code, which I then cleared.

So, to recap, the misfire appears to have subsided and there are no fault codes. I removed the spark plugs, and didn't find anything of concern. They all look similar and they don't look fouled: (1-4 in order from bottom to top; that's just a bit of tubing on plug 1 because the socket wouldn't grab it)



Here's plug 2:



So, back in went the same plugs, this time with 2 and 3 swapped. The plan is to drive it as much as possible to induce the misfire, then scan it, see which cylinder it is.

I've got the new plugs waiting for if and when they're needed.

So I'm a bit stumped for today. The car pulls like a train and is as smooth as it gets. No fault codes. But I know something aint right.
Did you check for any hair line cracks on the insulator white part?.

Offline AJP

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 392
  • -Receive: 316
  • Posts: 3212
Re: Spark plug gaps
« Reply #22 on: August 21, 2016, 01:55:13 pm »
I wasn't specifically looking for cracks but I had a good look and didn't notice any. All the plugs looked very good, which I'd expect with them being 2k old.

One thing I did notice was that plug 4 was really tight compared to the other 3.

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: Spark plug gaps
« Reply #23 on: August 21, 2016, 01:57:38 pm »
I think you should take them out again and have a good look around thr insulated for cracks although it'd be a continuous misfire if one was cracked.

Offline AJP

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 392
  • -Receive: 316
  • Posts: 3212
Re: Spark plug gaps
« Reply #24 on: August 21, 2016, 02:02:45 pm »
I think you should take them out again and have a good look around thr insulated for cracks although it'd be a continuous misfire if one was cracked.
I will do. Although I agree, the intermittent nature of the misfire logically points to something other than plugs.

I guess if an injector is dying, it might work fine one day but not the other. It's just a solenoid after all.

Offline Pesky jones

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 2
  • -Receive: 19
  • Posts: 1639
Re: Spark plug gaps
« Reply #25 on: August 21, 2016, 02:18:19 pm »
Thats wierd! It would be hard to just "leave" the problem alone (if there is one still) without knowing why. Plus if it does come back in 6 monthes you'll be annoyed you didnt fix it the first time. Can't really help much unfortunately but i think eliminating the plugs and coils is a good start.

Offline AJP

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 392
  • -Receive: 316
  • Posts: 3212
Re: Spark plug gaps
« Reply #26 on: August 21, 2016, 02:40:17 pm »
Thats wierd! It would be hard to just "leave" the problem alone (if there is one still) without knowing why. Plus if it does come back in 6 monthes you'll be annoyed you didnt fix it the first time. Can't really help much unfortunately but i think eliminating the plugs and coils is a good start.
It is an odd one isn't it. I'd like to get the new plugs in, but I'd rather get it to log a misfire on the current plugs with 2 & 3 swapped so I can at least rule them out. If it misfires again on 2 then in theory it's not the plugs. So I can either leave them in (they're 2k old) or put the new ones in. Either way I can't see it making much difference if that's the case.

I'm supposed to be driving 200 odd miles to Wales at the start of September, and even if the misfire doesn't come back before then I'm not sure I'd be confident risking the drive.

Bit of a predicament!

Offline Dan_FR

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 132
  • -Receive: 189
  • Posts: 1845
  • wait...what?
    • Email
Re: Spark plug gaps
« Reply #27 on: August 21, 2016, 02:41:14 pm »
Don't rely on fault codes. You need to see the misfire counter to ensure there are no misfires. OBD2 scanner isn't enough here.  Find someone with VCDS
TFSI... Revo Stage 2+... . WMI.... VCDS HEX + CAN, MPPS, VAG Commander & VAG tacho - South Wales

Offline fab5freddy

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 238
  • -Receive: 239
  • Posts: 2033
Re: Spark plug gaps
« Reply #28 on: August 21, 2016, 02:48:46 pm »
I should have added in previous posts, mine never threw a fault code, I have VCDS and scanned it regularly. I have a Polar fis and I can see misfires as they happen, but they were never logged, so to speak, so even though I knew and could see it on the polar, when scanned with VCDS, nothing.

« Last Edit: August 21, 2016, 02:51:03 pm by fab5freddy »

Offline Pesky jones

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 2
  • -Receive: 19
  • Posts: 1639
Re: Spark plug gaps
« Reply #29 on: August 21, 2016, 04:41:10 pm »
Where are you in the country?