I have a 1986 Mazda B2000 that I am having smog problems with here in CA. I had a low mileage engine put in about a year ago. At that time I added a rebuilt carb, new ecu, and new egr. Problem is when the egr is hooked up to vacume it will make the truck run rough as soon as the rpms go up. If its hooked up and you start it up cold and let it run it runs fine but as soon as you start to drive it, it stumbles and will almost die at the first stop. If you jump out and take the hose off of the egr then the rpms go back up to a nice idle and off you go. I have just been running the truck with it unhooked. Reg is due so it has to be smogged. I had a guy tell me it could be the pre-cat. That if its plugged the o2 is sending a bad signal to the ecu and making the carb run bad, to rich or to lean. I have a new pre-cat and rear cat to put on but does anyone have any other ideas? Like I said if the egr is unhooked it runs great, hook it up and it rpms at about 50. Greg
- posted
20 years ago