p0402 code i remove egr and modulator to clean, how do i test them before reins. on 2000 Toyota 4Runner

need to verify parts are good

Asked by for the 2000 Toyota 4Runner
1 answer
The code is for excessive EGR flow, check
For test procedures there is a company that independent auto repair shops get their information from, this same information is available inexpensively for people that work on their own cars.. The information is year make and model specific, covering repair procedures, torque specifications, fluid capacities and specifications, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate http://bit.ly/AllData_Repair_Manuals_Online
Honda and Acura (some old Nissans)end up clogging up some passages in the intake manifold allowing no EGR to get to some cylinders and too much to others causing a misfire. The vacuum switching valves and vacuum modulators fail on Toyotas but cause no EGR operation or intermittent EGR.