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I have a 2006 that is basically stock with CAI and 5in exhaust.. I have a max effort tune basically dialed in and it runs great!.. The only issue I have with it is when I am light on the throttle and getting up to speed it has a black haze coming from the exhaust.. I am trying to clean that up.. So far I have tried adding timing and subtracting timing in that region with no help.. Maybe I need to add or subtract rail pressure or pilot timing? Thanks
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How much timing have you removed, what is your timing at in the areas that you are having issues with. Boost limited fueling table will play a part in it, as well as timing. Have you adjusted Pilot?
3-4 degrees in that region.. I have gone down to 1-2 degrees.. and are you talking pilot timing or duration? I have pilot timing around 14 degrees and duration is stock.. Also my boost limit table is maxed out across the board.. maybe I should reset and adjust it little?
You can use your boost/fuel table to limit fueling in the areas you are having troublesome smoke, limit it too much though it can hurt acceleration.
Why would you have your boost limit table maxed out??! You are missing out on a lot of drivability and with that. I am often in ATDC timing in the light accel range, so -2 or sometimes even less.
Take care of your boost limit table first. Other than a 100% competition vehicle that should never just be maxed out, and even on competition vehicle I never max it out. It is very much necessary to keep things clean with a fixed vane charger.
I guess i just seen a limiter and wanted it gone lol changing that back to stock now
ahh gotcha, yea that is a limiter you want to use. You want the top end maxed out to your max fueling for sure. So usually on a stock turbo I'm at full 145mm3 by 12-14psi.
Ok! I reset it to stock for now and it didnt change the haze at all.. I am going to drop timing around -2* in that area to see if it helpsQuote:
Originally Posted by Dom_c13b
I just flashed a tune in with around -2* from 45mm3 to 95mm3, 1200rpm to 2000rpm and it seemed to clean it up a lot! Its getting dark now but i am excited to run it tomorrow some more to see how it does. Thanks guys!
Depending on what your rail pressure is in your haze area, a bump up in rail pressure in conjunction with dropping timing may help some as well.
Ok So to low of rail pressure can cause a dark haze? Light acceleration I'm around 13.5k-14k does that sound about right?Quote:
Originally Posted by Jim P
Depends on air flow, fuel flow, timing, etc.
One more question.. in the area where I am having the smoke issues the stock tune has post injection on.. Where is in my tune I turned it off.. Would post injection possibly help with the smoke?
It could, yes.
Ok thank you! I will give that a shotQuote:
Originally Posted by Jim P
I would start with stock post injection. What the post injection will do is remove a portion of your main injection and inject it later in the cycle, helping to burn fuel unburnt in the main event, raise turbo speed some as you will have a bit more heat later in the cycle and exiting the cylinders, improving lower speed air flow, helping with a bit leaner combustion. It can easy to over saturate the air/fuel mixture to a richer burn though leading to more smoke.
Thank you for the explanation! That was my plan to start with stock post and work from thereQuote:
Originally Posted by Jim P