[DavesRide]

That particular engine does not use an EGR (exhaust gas recirculation) system like other models. It used a means of altering the position of the exhaust cam to allow some of the exhaust gases to be pulled back into combustion chamber during firing cycle to increase reburn of unburned fuel. I would would take it to a modern shop, if not a reputable dealer, and have them properly diagnose it. The cost of repair may be less expensive than an ill-running engine in the long run. They don't get that good of gas mileage anyhow and you don't want to make it worse.
Other than 4 years of Art school I have been working as a tech at a dealer since 1989 up until Oct of 07. David