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Old Mar 15, 2007 | 07:46 AM
  #11  
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Default RE: misfiring

ORIGINAL: nickellis14

your car isn't misfiring because of an o2 sensor. My guess is you're running lean and detonating with the new turbo and higher boost. THIS IS A VERY BAD THING, as it can get hot enough to fuse your pistons to you cylinder walls (I hope I don't need to explain why this is a bad thing). until you figure out what is going on, I would NOT RUN THIS ENGINE. you apparently have a chip that can handle the k04, but your injectors may be too small, or may be too dirty to get enough fuel into the system. if you have a CEL check it. if it's telling you the o2 sensor isn't functioning correctly, but isn't saying you're misfiring, then there is a 90% chance you're running too lean and detonating.
the CEL returns misfires in cylinder 1 and a random cylinder.

the only reason i mention the o2 sensor is because giac says to have it replaced if you have more than 50k miles on it when you upgrade to their k04 package
 
Old Mar 15, 2007 | 07:46 AM
  #12  
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ORIGINAL: david9999

How old is your fuel filter?
I have no idea... since 1999? would that be a big problem?
 
Old Mar 15, 2007 | 07:46 AM
  #13  
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ORIGINAL: Bondga

just a shot in the dark here. but i had a random misfire code when my MAF got dirty. It also threw me into limp mode but maybe its just dirty enough to misfire but not cause limp. YOu could try cleaning maf and see if that gets you anywhere. and if not at least you have a nice clean maf.
I will take a look into cleaning that, thanks.
 
Old Mar 16, 2007 | 09:27 PM
  #14  
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okay, so I got the boost gauge finally installed. I am actually boosting very low, about 10-11 psi, spikes at 13 and vacuum is at 20in. I think I will have to check for boost leaks to see if I am running rich.
 
Old Mar 16, 2007 | 09:43 PM
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Default RE: misfiring

ORIGINAL: limptimtim

okay, so I got the boost gauge finally installed. I am actually boosting very low, about 10-11 psi, spikes at 13 and vacuum is at 20in. I think I will have to check for boost leaks to see if I am running rich.
Good idea!
 
Old Mar 16, 2007 | 09:56 PM
  #16  
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I read that wrong, vacuum is actually at about 18in. AWE-Tuning says it should be at 25 and boost should be at 18-19 psi. How significant are my numbers off (I don't know much about the significance of vacuum)?

When my car is off the gauge is a little to the left of 0 (into the vacuum side) at about 1in. of vacuum. Did I receive a faulty gauge or is there a way to calibrate this to 0?

Also, how much boost is actually lost to the boost gauge? Am I supposed to be able to hear the air going into the boost gauge, because I can clearly, but I don't think it is leaking there, I spent a lot of time redoing that part until I got it right.
 
Old Mar 16, 2007 | 10:11 PM
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Default RE: misfiring

ORIGINAL: limptimtim

I read that wrong, vacuum is actually at about 18in. AWE-Tuning says it should be at 25 and boost should be at 18-19 psi. How significant are my numbers off (I don't know much about the significance of vacuum)?

When my car is off the gauge is a little to the left of 0 (into the vacuum side) at about 1in. of vacuum. Did I receive a faulty gauge or is there a way to calibrate this to 0?

Also, how much boost is actually lost to the boost gauge? Am I supposed to be able to hear the air going into the boost gauge, because I can clearly, but I don't think it is leaking there, I spent a lot of time redoing that part until I got it right.
WOW if you are supposed to be at 25 then I am more off then you!!! I am at about 12 at idle and boost about 7-8 psi (which drops off quite quick at higher RPMS). I am running stock everything. I think I am going to make a post about that.

Josh
 
Old Mar 16, 2007 | 10:15 PM
  #18  
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Default RE: misfiring

vac should be close to 20 at idle.. Sometimes mine goes to 25 though, sometimes not. No boost should be lost with the gauge.. You shouldnt hear any air around the gauge.. Some VDO gauges buzz a little, but you should def not hear anything other than that at the gauge.
 
Old Mar 16, 2007 | 10:17 PM
  #19  
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Default RE: misfiring

My vacuum plays between 19-23. Too low of a vacuum reading can be a vac leak (ie. leaking/damaged vac hoses), too high can mean some kind of intake restriction (ie. dirty air filter) amongst other things.
 
Old Mar 16, 2007 | 10:21 PM
  #20  
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Default RE: misfiring

Crap so i get to go through all the hoses and find it? I know how to find a boost leak, will that work for a vac leak to?

Josh

P.S. would that cause the car to run rich? Just wondering. I saw that if your plugs are black you are running rich and last time I changed my plugs they were pretty black, some were dripping a little. I am going to check my new ones today maybe and see what they look like.
 



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