Bad spark plug symptoms?
05-11-2007, 08:35 AM
#1
Thread Starter
Bad spark plug symptoms?
I recently swapped from IK24's to NKG copper plugs BKR7E gapped at .035" for a supercharged application. Now the car is experiencing some strange issues.
-- Exhaust periodically pulses on idle.
-- Taking off from a stop in 1st gear at 1500-2500rpm exhaust sputters/pulses, there is a loss in power but once i'm about 3000rpm and the car is moving everything seems fine
-- car operates normally in other gears and past 3000 in first.
I thought my plug gap was too large so I regapped them at .033" I've also swapped out the MAP sensor with the new one and filled up with a fresh tank of gas. issues persisted.
Are these symptoms of a bad spark plug? Or could it be something else (injectors, coils, valves?) I haven't had a chance to swap the IK24 plugs back in.
-- Exhaust periodically pulses on idle.
-- Taking off from a stop in 1st gear at 1500-2500rpm exhaust sputters/pulses, there is a loss in power but once i'm about 3000rpm and the car is moving everything seems fine
-- car operates normally in other gears and past 3000 in first.
I thought my plug gap was too large so I regapped them at .033" I've also swapped out the MAP sensor with the new one and filled up with a fresh tank of gas. issues persisted.
Are these symptoms of a bad spark plug? Or could it be something else (injectors, coils, valves?) I haven't had a chance to swap the IK24 plugs back in.
05-11-2007, 01:29 PM
#5
Registered User
Join Date: Mar 2005
Location: all up in your grill
Posts: 20,875
Likes: 0
Received 0 Likes
on
0 Posts
Alan, the BKR7E is the same heat range as stock. I'd suggest a colder plug like the R5672A-8 (7173 NGK copper racing plug), or the IFR8H-11 (5068 NGK Iridium). Both are one step colder than stock, which is good for FI. That may have something to do with the issues you're having. 
05-11-2007, 01:30 PM
#6
Registered User
Join Date: Mar 2005
Location: all up in your grill
Posts: 20,875
Likes: 0
Received 0 Likes
on
0 Posts
BTW, I wrote a novel about this a couple months ago 
https://www.s2ki.com/forums/index.php?showt...0&#entry9655960
https://www.s2ki.com/forums/index.php?showt...0&#entry9655960
05-11-2007, 01:46 PM
#7
Thread Starter
I doubt it is bent valves since I've only recently taken it out of storage and been grannying it around a couple of weeks.
This weekend I'm going to go put back to the IK24 that were in their before. I've actually had the supercharge on for a year with the stock plugs before switching to the IK24's, it ran fine at stock heat range.
Doing some research I noticed that WLaurent had the same problems last month. He seemed to have cleared it with a valve adjustment.
https://www.s2ki.com/forums/index.ph...ic=478799&st=0
This weekend I'm going to go put back to the IK24 that were in their before. I've actually had the supercharge on for a year with the stock plugs before switching to the IK24's, it ran fine at stock heat range.
Doing some research I noticed that WLaurent had the same problems last month. He seemed to have cleared it with a valve adjustment.
https://www.s2ki.com/forums/index.ph...ic=478799&st=0
Trending Topics
05-13-2007, 07:46 PM
#8
Thread Starter
Just so I don't leave this thread dangling. I swapped in 4 new plugs and the car seems to be running well now! Looks like I got a bad plug from NKG.
For 2 bucks a pop, I didn't bother trying to figure out which one it was so I tossed all 4 out. Sleeping sounder now that the car is happy.
For 2 bucks a pop, I didn't bother trying to figure out which one it was so I tossed all 4 out. Sleeping sounder now that the car is happy.
Thread
Thread Starter
Forum
Replies
Last Post