Boost Issues Plus Running Rich, 96 855R

rmorse · Post by **rmorse** » 23 Jul 2012, 14:42

Hey guys,

I'm still trying to chase down everything and make things as close to perfect as I can, before starting real performance upgrades. Anyway, my car has been (I thought) running awesome lately, but it seems I was mistaken.

I installed an IPD boost gauge yesterday and was playing around with it. My friend was following behind and watched me hit it hard. When we stopped, he said he my car was running rich -- black smoke came out when I was stepping on it and the exhaust smelled rich. That's problem numero uno.

Problem numero dos -- my boost levels. I am in vacuum at idle, at about 15-18. When I put it in sport mode and go WOT, I stay at 5 psi. Consistently. No fluttering, no fade. Solid 5 psi. It always felt strong though, but this is also my first car like this so I don't have too much to compare to. I did a 0-60 time, with my girlfriend next to me timing, and it was 9 seconds.

Any advice?

I'm thinking:
Worn turbo
Bad CBV
Bad BCS
Wrong Wastegate Settings

PCV was done about 5-10k miles ago, but positive pressure remains. I need to drop the oil pan and swap out the o-rings.

JordanW · Post by **JordanW** » 23 Jul 2012, 15:13

Stock 850R tune, or are you running something else?

Unlikely it's a turbo. Your vac readings, are those in park, warm engine, and A/C off? I would cheack for boost/vacuum leaks including the lines from the BSC to the turbo. 18-20in hg at idle in park ac off engine warm are good numbers.

How are your "Stage 0" items? Plugs, cap, rotor, fuel filter, air filter? Do you have a CEL? Have you ever replaced your MAF or O2's?

With my ARD Green M4.4 tune, I've seen some black smoke at WOT and full load, albeit briefly. I was like WTF at first, then I laughed cause I also smoked the "stang GT" next to me.

rmorse · Post by **rmorse** » 23 Jul 2012, 15:18

Thanks for the reply. For your questions:

Stock 850R tune. I do have Snabb fresh air pipe and IPD SR5T intake.

Vac readings in park, warm engine, A/C off. All lines from BCS to turbo, plus one other line going to the turbo, have been replaced with quality silicone.

No CEL, Stage 0 performed 10k-15k miles ago. Never replaced MAF or O2's, only had the car for 1.5 years.

Hope that helps!

rmorse · Post by **rmorse** » 24 Jul 2012, 06:44

Bump...

Post by **matthew1** » 24 Jul 2012, 10:24

If that was my 850, I'd clear codes and disconnect the negative terminal for a few minutes. Reset things simply to ensure it's not a silent code.

If it's not that, I would go over the basics again: air leaks, vac leaks, fluid leaks, smoke, low fluids, air filter, spark plugs, MAF, etc. Swap the MAF with a blue box/known-good MAF.

Post by **jblackburn** » 24 Jul 2012, 10:41

I'm thinking look for a torn intercooler hose or cracked intercooler.