Running Rich - Read Spark Plug Photo

[Satinsax]

JZW Stage 4 - 2000 9-3 SE Vert Automatic

Mileage is down. Plugs are 7es gapped to .036

I drive mostly stop and go (mostly stop) in city...Some "very spirited" driving.

Just pulled the plugs yesterday...They are all uniform as the photo..

Should I go back to 6es plugs (maybe it's not burning enough on stop and go)

[jtdesignsca]

Originally Posted by Satinsax

JZW Stage 4 - 2000 9-3 SE Vert Automatic

Mileage is down. Plugs are 7es gapped to .036

I drive mostly stop and go (mostly stop) in city...Some "very spirited" driving.

Just pulled the plugs yesterday...They are all uniform as the photo..

Should I go back to 6es plugs (maybe it's not burning enough on stop and go)

Those look pretty clean to me...what kind of drop in MPG's did you see? I would log another tank of gas and see where your at, may have been just stop and go (traffic) that dropped it.

JT

[Satinsax]

The mileage is down to about 17 city/highway combined.

I have noticed that my boost/vac guage is showing about 3hg less of vacuum at idle (in gear). All vac lines look good. I sprayed looking for vac leaks and can find none.

[jtdesignsca]

What MPG where you reading befor the drop? My Vac varies 3hg depending on outside temp, pressure, etc. so I don't think that's to worry about. It is starting to get warmer there no?

JT

[Satinsax]

Was 22mpg...My hg at idle in gear was always 17-18. Now hg is 13-15.

[jtdesignsca]

that is a little low...I'll see what I can find out.

Anyone else have input

JT

[Satinsax]

I've checked and double checked all vac lines...most are silicon..BPC hoses are new...could the forge BPV cause a lower vac reading or the BPC...both are new...the only old part left is the Purge Valve...every other sensor has been replaced as well.

[saabkid37]

you really cant truly read plugs in a saab...the di has a cleaning cycle after you shut down the car, so it wont be totally accurate.

[Gunnar]

Those definitely do not look like the NGK plugs you should be using...

[fiveiron9688]

He said he's using NGK's.

It could be the BPC. I purchased a used one (which I later found didn't work properly) and it definitely screwed with my idle and vacuum a bit, although not continuously. Swapped out with a different used BPC, and we're good now!

If you're sure the BPC is fine, and you've checked ALL of those vacuum hoses, I'm not really sure... My plugs look similar to your's, I don't really think that's the problem. I could be wrong though!

[Nicole]

I'm curious: Does your exhaust tip turn black at the lower rim?

My car gets 21mpg, has some cold running issue, and if I clean the exhaust tip, it turns black again at the lower rim within about 30-40 miles.

This is not my car, but the exhaust tip looks the same:

[Gunnar]

Originally Posted by fiveiron9688

He said he's using NGK's.

It could be the BPC. I purchased a used one (which I later found didn't work properly) and it definitely screwed with my idle and vacuum a bit, although not continuously. Swapped out with a different used BPC, and we're good now!

If you're sure the BPC is fine, and you've checked ALL of those vacuum hoses, I'm not really sure... My plugs look similar to your's, I don't really think that's the problem. I could be wrong though!

I'm fairly certain the NGK plugs that are supposed to used do not have that big of a point. I just put in new NGK plugs last week and the points were very small not like the large round shape you have pictured.

http://www.gpmotoparts.com/image.php?type=P&id=19281

Like this one.

[lms]

Better rich then lean when you have a tune and those plugs look fine, but maybe a tad old, drop gap to .34 and do not change heat. Plugs are not going to increase mileage unless they are shot. Maybe it's the change of fuel (winter to summer gas) and the fact that there is no snow and were all flogging it now that the roads are somewhat dry. Winter I get better mileage as I'm putting around more.

[daytonmvp23]

Ok so the plugs look like the standard copper ngk as they have bigger nubs compared to plats and iridiums. The only thing noticable is the white ash deposit which would suggest too much fuel additives. so if you are using SHELL ultra and then putting in some other additive like say octane boost or fuel cleaner constantly that is why your plugs look that way. Plus if I remember correctly Trionic can read octane ratings and if you go low octane it goes into (as I call it ) granny mode. less performance and better fuel economy where as high octane nets better performance and less fuel economy especially if you flog it! I noticed the drop in MPG as well when I put 95 octane in even when keeping driving conditions similiar. This more noticable on my trionic 7 Saab 9-5 then my trionic 5 9-3. But you could always get a vacuum tester and do a vacuum test of the system first. Or get a leak down or compression tester and make sure everything is good in that regards. If you have the cash leak down and vacuum are the 2 best ones to get to check the health of your engine.

[Satinsax]

Originally Posted by Gunnar

Those definitely do not look like the NGK plugs you should be using...

They're NGK BCPR7ES....standard plugs

[Satinsax]

The plugs need to be NGK Copper...the ones with a point are platinum or iridum...DIs don't like them

Originally Posted by Gunnar

I'm fairly certain the NGK plugs that are supposed to used do not have that big of a point. I just put in new NGK plugs last week and the points were very small not like the large round shape you have pictured.

http://www.gpmotoparts.com/image.php?type=P&id=19281

Like this one.

[Satinsax]

Yes my exhaust tip does turn black right away...

Originally Posted by Nicole

I'm curious: Does your exhaust tip turn black at the lower rim?

My car gets 21mpg, has some cold running issue, and if I clean the exhaust tip, it turns black again at the lower rim within about 30-40 miles.

This is not my car, but the exhaust tip looks the same:

[Satinsax]

Good advice...I do have a mityvac...and I do use Shell ultra but I don't use any additional additive. I'll run through the vac lines again and I think I have another BPC to try out.

Originally Posted by daytonmvp23

Ok so the plugs look like the standard copper ngk as they have bigger nubs compared to plats and iridiums. The only thing noticable is the white ash deposit which would suggest too much fuel additives. so if you are using SHELL ultra and then putting in some other additive like say octane boost or fuel cleaner constantly that is why your plugs look that way. Plus if I remember correctly Trionic can read octane ratings and if you go low octane it goes into (as I call it ) granny mode. less performance and better fuel economy where as high octane nets better performance and less fuel economy especially if you flog it! I noticed the drop in MPG as well when I put 95 octane in even when keeping driving conditions similiar. This more noticable on my trionic 7 Saab 9-5 then my trionic 5 9-3. But you could always get a vacuum tester and do a vacuum test of the system first. Or get a leak down or compression tester and make sure everything is good in that regards. If you have the cash leak down and vacuum are the 2 best ones to get to check the health of your engine.

[daytonmvp23]

Stage 4 JZW upgrade do you have the bigger fuel pump, injectors, and an adjustable fuel pressure regulator(FPR)(with gauge)? If not this is where I would start looking. Also does it still shift like it should or at least like it had before the problem start occuring?
If you have not done the upgrades to the fuel system specifically the FPR and injectors I would suspect these 2 maybe the culprit as the FPR diaphram maybe overloaded and the injectors running over their normal duty cycles. Plus since it is a 2000 it has a knock sensor right? So it could be giving false signals (but would normally throw an engine code) making the system run rich by retarding the timing too much.

[Gunnar]

Originally Posted by Satinsax

The plugs need to be NGK Copper...the ones with a point are platinum or iridum...DIs don't like them

Hmm, never realized that. Then again I don't have to worry about that crap, 2.3 n/a.