'03 9-5 2.3T 4 cylinder / MIsfire Solution / fixed

[photousa]

Recently, I took my '03 9-5 Wagon, (current mileage about 136K) into an indy for a Tech II pairing of a used SID and my cars brain. While I was there, the tech mentioned that he could feel a misfire. The car was stumbling and had an intermittent misfire that you could feel in the seat of your pants. The misfire wasn't enough to throw a code, but he was able to detect using Tech II that I had a misfire with cylinder 2. His advice was to check the gap on all of my plugs. After I purchased a feeler gauge that would read, .90mm, .95mm and 1.0mm, I started pulling my plugs to have a look at things. My plugs, NGK PRF6H-10, ( Part #6290 ) were installed new, along with a new dealer installed DIC 17,000 miles ago. I discovered that the #2 Cylinder plug had a crack in it's ceramic collar, (the yellow arrow in the photo points to the crack in the ceramic). I didn't want to drive the car after seeing this, so I was lucky and found a replacement plug at a local Car Quest, ($17.00). Re-gapped all plugs to .95, reinstalled everything and the car is back running as smooth as a Swedish clock. The Haynes manual says these plugs should get swapped out at 24,000 miles, so I should be set for a while. I was a little baffled by this problem, since recently, I had completely cleaned out my throttle body and it had a relatively new DIC. Now, if I can only figure out why the ceramic cracked. Wanted to post a solution for once, all we seem to see around here are the problems that come up..
Spark Plug Torque: 28 nm
Direct Ignition Cassette screws: 12 nm

[nordwulf]

The Haynes manual says these plugs should get swapped out at 24,000 miles, so I should be set for a while.

The WIS shows these should be replaced every 40K-45K miles, depending on the model year. They should last longer than 24K miles.

http://saabworld.net/f144/saab-9-5-m...on-system-578/
http://saabworld.net/f144/saab-9-5-m...on-system-583/

I checked mine at 45K miles and they were still within specs. No need to re-gap the new ones as they were already set to the correct gap.

[Burnsside42]

Platnium plugs vs the cheaper plugs - one is good for longer then the other. One cost twice as much.

[photousa]

The WIS shows these should be replaced every 40K-45K miles, depending on the model year. They should last longer than 24K miles.

http://saabworld.net/f144/saab-9-5-m...on-system-578/
http://saabworld.net/f144/saab-9-5-m...on-system-583/

I checked mine at 45K miles and they were still within specs. No need to re-gap the new ones as they were already set to the correct gap.

Hey, that's great news, thanks for posting Frank. The owners manual says which plugs are to be used, just says nothing about the recommended change internal. I've contacted NGK with questions as why the ceramic would crack, I'll follow up once I speak with technical assistance.