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Old 08-22-2008, 03:52 PM   #1
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Default Not running right

My damn laptop refuses to connect to MS, so I need some help (if possible) until I can get it to.

I'm running 10psi with a TPS.

My car lately has been smelling like burning while under boost and when I let off the gas at high rpm and let the engine wind down. The back bumper is black above the exhaust. During cruise it feels like one cylinder doesn't fire every now and then. When I hit the gas there is a slight hesitation there at first and it feels like the engine is going to stall and then it starts to rev.

My lc-1 (could very well be the problem) shows AFR to be just fine under boost. The car was fine about 2 weeks ago when we were tuning it. I never hear knock and the oil pressure gauge never wiggles.

The oil feed line is -4 with no restrictor in it. I never had a problem with the turbo seals before, so I don't think it's oil. The clutch is shot to hell. Not sure if that would make a difference. I thought the smell was the clutch at first.

I want to make a log and pull the plugs and all that soon. If my computer lets me I will. Any thoughts?
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Old 08-22-2008, 10:00 PM   #2
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I pulled off the intake and looked in the turbo, there is a light film of oil on the housing. It would appear at 10psi the -4 feed line is pushing oil past the seals. Maybe the oil film is getting on the o2 and screwing it up. Would explain the good AFRs but the black soot.

What is the right way to restrict it? I'll go check ATP turbo for restrictors, hopefully they have them because I need a new drain flange anyway.

Edit: I want to pull off the charge pipes and check for oil but this damn weather. 80F with 75% humidity. I'll try for tomorrow.
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Old 08-22-2008, 10:44 PM   #3
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Couldn't resist and went and pulled off the charge pipes, not a drop of oil. I think the residue is from when I had the breather line routed to the intake.

Next is to check the fuel injector seals. I noticed two are deep in the intake and are hard to rotate while the other two stick out and are easy to rotate.

Damn this problem. If I could pin point when this started I would have an idea of what it was. Now I don't think this is MS itself related anymore.
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Old 08-22-2008, 10:49 PM   #4
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just remembered and thought i'd post it here instead of reply to your pm.

what is the situation with the pcv valve? did you get the gtx pcv or the one-way valve i told you about?

my feeling is your pcv is leaking and letting boost into the crankcase. rings may not be sealing as a result.

any other thing causing a rich/lean condition would have shown up in your afr gauge. but that's not happening like you said.
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Old 08-22-2008, 10:57 PM   #5
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I sent you a PM, pretty much what I said above.

I'll look into the PCV valve. I have an aftermarket one, wouldn't be surprised if it's bad. I notice the smell the worst when I let the engine coast down.
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Old 08-23-2008, 08:58 PM   #6
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Found two problems. The injectors were leaking a tiny tiny bit, I got some new seals from work and fixed it.

My PCV is leaking like a bastard. Not sure when it started, but looks like it is the cause of my problems. Looks like it was only good for 2k miles.
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