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Two issues fixed more pop up???

So after weeks of knocking my head around why my car was running like crap I finally got off my lazy ass and did something about it. So today I pulled the spark plugs and found out that two of the plugs(ngk bpr6es) were gapped way too wide above 0.032 so I decreased the gap down to about 0.028. This cured one of my issues spark blowing out at 20-25psi btw mbc not installed. I suspect my waste gate is failing on my turbo setup.The plugs seemed to be in good condition as they were not fouled or soaked with oil(thank god) they were however a little on the lite tan colored side which would lead me to believe that there is a lean condition my tailpipe tells another story as it is soot black? The other issue I discovered was that I was missing an exhaust manifold stud, the one that is furthest to the right on the bottom next to that big piece of iron that supports the power steering pump. I could not get a stud in there so I just found an appropriate size bolt I think 8x1.25 about the same length as the stud I measured and that cured another of my exhaust leaks. I still need to figure out a solution for the mis-match between the O2 housing and the bigger opening on my 3" BR down pipe I guess the O2 is only 2.5 or 2.75 while the DP is 3". After fixing these issues I realized that my aem WB was now reading a little lean afr's were max lean(wide band) at idle and in the 12's at wot and more knock than usual. I added a bit more fuel on the aeromotive fpr and richened things up a bit this brought the afr's back to 14's at idle and 11's at wot with only 3-4 counts of knock at wot /ubbthreads/images/graemlins/smile.gif usually in 2 or 3 gear and above 20psi. On my way home I stopped to check things over and from beneath my exhaust manifold shield the turbo hot side looked like a xmas tree it was cherry red I don't recall seeing it this red is this normal? The fuel trims are now also a little out of whack Low 81.2 Med 99 Hi 89. I am not so concerned about the fuel trims just want to make sure that this thing isn't running lean and do any damage. Am I being paranoid or does the housing get that hot from what I could see the manifold nor O2 housing wasn't.Thanks for reading and sorry for the long post.Other than that the car runs like a raped ape above 20psi albeit with a few counts of knock.

Mods-evoix mr mas,iceman pig tail adapter,fic 850cc,mhi b16g,2g manifold and O2,aem wide band,walboro rewired 255,BR 3" turbo back exhaust,act clutch and flywheel,dsm logger,dejon tool intake pipe,stock intercooler(installing front mount any day),apexi boost gauge and keydiver 91-94 ecu with the works setup for current mods......
Thanks.....
 

ktmrider

Well-known member
Joined
Sep 10, 2007
Messages
3,128
Location
Tempe, AZ
Tan spark plug color = good. White and/or flecks = lean.

Running 20+psi on BR6 plugs and stock IC is one reason for your knock. At a minimum switch to BR7's or ideally BR8's and gap no larger than 0.028".

Stock IC is a reason for "low" unregulated boost, can't shove that much air thru such a small restriction. Try breathing fast thru a straw sometime for the effect. Another is leaks after the MAS or BOV venting to atmosphere.

Soot black tailpipe and glowing red turbo/mani = unburned fuel from a poor combustion cycle. Unburned fuel is re-igniting in the hot mani/turbo causing the "glow" and soot deposits.
 
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Tan spark plug color = good. White and/or flecks = lean.

"I will take a pic of the spark plugs and post later"

Running 20psi on BR6 plugs and stock IC is one reason for your knock. At a minimum switch to BR7's or ideally BR8's and gap no larger than 0.028"

"I have some BR7's I will get those installed today asap"

Stock IC is a reason for "low" unregulated boost, can't shove that much air thru such a small restriction. Try breathing fast thru a straw sometime for the effect. Another is leaks after the MAS or BOV venting to atmosphere.

"Front mount will have to wait until I get back from sema las vegas.I will also use my boost leak tester to see if I have any boost leaks also"

Soot black tailpipe and glowing red turbo/mani = unburned fuel from a poor combustion cycle. Unburned fuel is re-igniting in the hot mani/turbo causing the "glow" and soot deposits.

"Ok got it I will keep the boost down(less right foot) a little I guess until then I may also need to switch to an external wg my car shouldnt be boosting 20psi with no mbc I think my wg is shot"

Thank you. /ubbthreads/images/graemlins/banghead.gif

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Last edited by a moderator:

I finally got around to installing the bp7res and gapped them down to .028 and no more misfires. I am still however fighting with the making the target afr 11's,knock and fuel trims play nice together looks like I may need that dsm link V3 after all.Well the battle continues I bought a new fuel filter and a new knock sensor that I will also install this week I am also going to pick up a new tstat sensor......I need to get the tune correct on this thing before building a new motor.
 
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