2001 68,800 miles.
When I bought the car it came with a ziptech 02 simulator connected to the ECU. Could this simulator cause the car to have misfires if its bad or not hooked up correctly. The car runs great except for an occasional stutter like its bogging. Plugs look good and were replaced, idle is perfect. What the heck could be going on?

 

It's wired into the MAP and TPS inputs so yes if the splices are bad it can cause running problems.

 

It doesn't make any sense to rush on getting something installed and do it poorly. I wish I could talk to the previous owner and ask him what the heck he was thinking. I got the car from a dealer who told me that the car was adult owned and everything was professional installed, it appears other wise.

I will check out the wiring and see if that is the cause. Is there any type of diagram I can go off of? Thanks for the quick reply.

 

One other thing you should know. There is also an Air/Fuel narrow band gauge installed. Can this possibly effect anything. Most of the time the lights bounce inbetween but when the car stutters I see it deep into the lean. This is only occassionally and most of the time it runs great.