AskPatty Certified Female Friendly Logo
i recently took my 1992 buick regal custom 3.1 litre 4 door in for an E-test and passed all the requirements except for a high NOx ppm what can i do to fix this problem so it is completely passible for driving

Answers from the Automotive Experts

Lori Johnson, Owner and Instructor at Ladies Start Your Engines Dear Jeff, High NOx means that your combustion chamber is burning hot.You could check your timing...do you have pinging? This could indicate a timing problem. Carbon deposits are possible too and probably the easiest to fix. You could de-carbonize the engine. This involves having someone inject a cleaner into the system, then taking the vehicle out for a drive and then changing the oil. Make sure you take your vehicle only to a technician who is ASE certified. You can find one in your area by going here: http://www.ase.com/bluesealsearch/locator.php

Contribute to this question:


blog comments powered by Disqus

Related Buick Regal FAQs


  • Where is the low pressure fill point on the air conditioner? Is the low, the small one ... Read More
  • Hi Patty, The air conditioner on my 93 Regal is not working. Last year my mechanic ... Read More
  • do you need brake fluid flushed and how much should it cost? Also, fuel induction system ... Read More
  • I am having trouble getting the keys out of the ignition when I turn the car off. ... Read More
  • our daughter has a 1993 buick regal 3800, it is low on radiator fluid we think, but there ... Read More
  • rear brakes 89 buick regal how to change cylinder Read More

Need Car Advice?

Ask The Experts!

Find Cars For Sale

Help Our Charities