I just took my '94 powerstroke with 135k in for its annual emmissions test. After setting the superchip back to stock, the truck blew 34% which just barely passes -- 35% is the allowable limit. I also had a 50-50 blend of biodiesel and regular diesel in the tank. Biodiesel substantially reduces particulate emmissions, so it's quite likely the truck would have failed with 100% diesel. The guy doing the test told me that most powerstrokes with similar miles blow about 10%. The other mods I've done besides the superchip are 4" exhaust, K&N air filter, and 3:55 gears replacing the stock 4:10.


Any suggestions as to what might be causing the high particulates?


Thanks

Sounds like poor boost from the turbo. Proper boost should clean up the burn to well below allowable limits. You might check all the connections and make sure you dont have a leak somewhere. It seems with those high numbers, youre probably seeing a bit of soot / smoke. Any guage for the boost ?

I seem to be blowing too much black smoke on mine too . I have a boost gauge on mine and it seems to run about 7 lbs of boost at 70 mph if that helps you out at all.


Edited by: Toreador

Interesting, mine sees abput 2 psi at 70 with no headwind on level ground.

You must be dreaming about using only 2 lbs of boost at 70 mph. You better pinch yourself! Hard http://www.dieselplace.com/forum/smileys/Big Smile.gif


Are you using a valet switch?


Edited by: Toreador