1991 Isuzu Trooper Repair Question
Topics covered: Sensor, Catalytic converter, Coolant.
Mileage: 90,467 miles.
Mileage: 90,467 miles.
Asked on February 21, 2012
Smog fail on NO
Would not pass smog I ended up replacing headgasket, valve job, valve lashcomplete tune up, all new vacuum lines and pcv, sensors ect. It still failed just barely, it failed NO
max is 704 @ 15 mph it measured 854
max is 606 @ 25 mph it measured 638
tech checked egr working fine
tech suggested changing timing from 13 degrees to 9 degrees
Any Ideas?
max is 704 @ 15 mph it measured 854
max is 606 @ 25 mph it measured 638
tech checked egr working fine
tech suggested changing timing from 13 degrees to 9 degrees
Any Ideas?
Asked by mkelee@cox.netAnswer
Replied on February 21, 2012
Check the EGR valve, a problem with it will caused the Nox -oxides of nitrogen to go high due to excessive combustion temperature
Replied on February 21, 2012
The tech checked it out using a vacuum pump/gauge said it was working
Replied on February 21, 2012
Tell him check the catalytic converter, oxygen and coolant temperature sensors-