What makes a Jeep Wrangler fail a smog test?
NOx was the last addition to the list of monitored exhaust gases. Misconceptions regarding the conditions that promote its formation still exist. I am working on a 1995 Jeep Wrangler with a 4.0L engine that has failed to pass a smog test due to high NOX.
Why does my Jeep 4.0L have high NOx?
While the columns did deal with a driveability problem on a Jeep 4.0L, the problem was entirely different from what your customer is experiencing. Second, a lack of backpressure caused by the aftermarket exhaust system should not cause an increase in NOX, at least not on a vehicle that’s capable of adjusting its own air/fuel ratio.
How old do you have to be to pay for smog abatement?
4. Owners of vehicles less than 4 model years old can pay an Annual Smog Abatement Fee for the first 8 registration years instead of being required to provide a biennial smog certification.
What can be done about high NOx in smog?
The solution to this problem is called De-Carbonizing. It usually costs around two labor hours at a smog check repair station. It will remove a good amount of carbon out of an engine. This will increase combustion space, lower compression and lower NOx. 5. Engine Overheating – Inadequate engine cooling can will high NOx.
What are the NOx levels in my car?
I also installed a NOX-reducing cat. After these changes, it barely passed the 15-mph emissions test and still failed the 25-mph test for NOX. The exhaust readings at cruise are as follows: CO, .01%; HC, 12 ppm; CO2, 15.0%; NOX, 917 ppm.
NOx was the last addition to the list of monitored exhaust gases. Misconceptions regarding the conditions that promote its formation still exist. I am working on a 1995 Jeep Wrangler with a 4.0L engine that has failed to pass a smog test due to high NOX.
While the columns did deal with a driveability problem on a Jeep 4.0L, the problem was entirely different from what your customer is experiencing. Second, a lack of backpressure caused by the aftermarket exhaust system should not cause an increase in NOX, at least not on a vehicle that’s capable of adjusting its own air/fuel ratio.
I also installed a NOX-reducing cat. After these changes, it barely passed the 15-mph emissions test and still failed the 25-mph test for NOX. The exhaust readings at cruise are as follows: CO, .01%; HC, 12 ppm; CO2, 15.0%; NOX, 917 ppm.
Can a car control NOx without an EGR valve?
Automotive engineers must agree because many vehicles now manage to control NOX without the help of an EGR valve. The Jeep you’re working on is one such vehicle. But everything else must be working properly if the EGR valve crutch is removed.