I have a feeling the problems might be associated with more a lean-burn problem rather than a sparkplug problem. Are you running stock boost levels?
Like Legacy777 stated, I wouldn't recommend colder range plugs until after at least 12psi, moreso 18psi. I am running a colder range plug but I'm also running a 16G with almost 17psi of boost. I'm considering taking out those old plugs and trying some stock range plugs. Current fuel consumption is ~20mpg.
hesitation. starting to think it's a big problem.
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- Knowledgeable
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Oh yeah, I betcha anything a lot it can be cleared out with *good* chip tuning. Manufacturers like to lean it out around the rpm's that primary resonance hits to help with emmissions.
I see some of you guys are playing around with repromming the ecu. What does that involve in terms of equipment and software?
I'm running stock boost i believe, just got the car. Need a boost gauge.
I see some of you guys are playing around with repromming the ecu. What does that involve in terms of equipment and software?
I'm running stock boost i believe, just got the car. Need a boost gauge.
92ss, 66bsa thunderbolt, 92miata, 06wrx
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- Knowledgeable
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Once you get the boost gauge monitor the boost at the 3000-4000rpm range (where you first hear knock). You might want to hook up a voltmeter to the O2 sensor output as well, just to make sure you're not running too lean. Also, what octane gas do you have in your area?
Some other items to check:
1. alternator
2. coil pack
3. plug wires
4. fuel filter
5. MAF sensor
Some other items to check:
1. alternator
2. coil pack
3. plug wires
4. fuel filter
5. MAF sensor
[url=http://www.angelfire.com/md3/91turbolegacy/images/On_the_Lawn.jpg]1991 Legacy Turbo (RIP)[/url]
[url=http://www.angelfire.com/md3/91turbolegacy/images/Summer_Car_Wash3.jpg]2000 Celica GT-S[/url]
[url=http://www.angelfire.com/md3/91turbolegacy/images/Summer_Car_Wash3.jpg]2000 Celica GT-S[/url]
progress report,
boostjunkie's post on the alternator being the problem clued me to start thinking electrical. Already did plugs, good change. Then I did plug wires, little to no change. Then cleaned large guage wire connections (terminals, alt, starter, body ground), some change.
Then I change out the crusty old battery, big change
. It must have built up a pretty good internal resistance. I'm stumble free now.
Gas around here is 92/89/87. I run 92.
boostjunkie's post on the alternator being the problem clued me to start thinking electrical. Already did plugs, good change. Then I did plug wires, little to no change. Then cleaned large guage wire connections (terminals, alt, starter, body ground), some change.
Then I change out the crusty old battery, big change

Gas around here is 92/89/87. I run 92.
92ss, 66bsa thunderbolt, 92miata, 06wrx
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I'm running colder plugs right now because I was getting what seemed like pre-ignition under load. I'm not sure if they made it any better though.... I can still hear it a little.
I still get over 30 MPG on the highway and the car runs fine
I haven't read the plugs yet, but I may do so in the next couple of weeks.
Andrew
I still get over 30 MPG on the highway and the car runs fine
I haven't read the plugs yet, but I may do so in the next couple of weeks.
Andrew
1990 Legacy LS Sedan FWD NA MT
209,000 miles!
2002 Impreza WRX Sport Wagon
http://www.myspace.com/petridish38
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209,000 miles!
2002 Impreza WRX Sport Wagon
http://www.myspace.com/petridish38
http://www.cardomain.com/id/petridish38
im getting hesitation and knocks as well. when ever it is part throttle and i am accelerating it pops like there is gas in the cats. this is at 2700 to 3200 rpm. it is driving me nuts. im going to check the plugs when tonight to see what are in there. if they're bosch they're as good as gone. i just had the heads rebuilt and i know my mechanic changed the plugs. the wire that runs to my knock sensor is basically rotted out, anyone know where i can get a replacement that including the plug on the end. could that be what is causing this. my car is bone stock right now. so i don't think that too hot of air would be the problem. wtf.
EJ22t Legacy and me: love at first sight.
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wow, this thread has helped alot, my car is running like CRAP right now. it does not like to hit boost, but altogether, it just seems like its lost ALOT of power. So first i did plugs, wires, and fuel filter. Matt from 555 motorsports recommended i gap the ngk bkr7e at .028, so tried that, ran AMAZING.... that night, next day, same problem, so i took out the plugs and they were pretty darn white, so i went and bought some 6e's what came on the car and put those in and gapped them at about .032.... so tomorrow im going to take them out and see how they look since you guys are saying they need to be gapped at .039-.043 if they are still white, im going to go buy some more and gap them at about .042 or so and see how that happens. also i need to replace my valve cover gaskets so one of my friends was suggesting possibly oil is getting on the plugs and fouling them? im not quite sure.
thanks in advance guys
thanks in advance guys
1991 Subaru Legacy SS 5MT: Revtronix Stage 2 Set-up with a few other "tasteful" mods :D
What boost are you running?
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
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