Join the community and post your question. Use our Ask-A-Tech for free now! ASE experts standing by.

Forum > Failed Smog Test > Question

1984 Fleetwood Southwind RV Chevy Engine High HC

My Fleetwood Southwind just failed a smog test because of high hc at idle. 700 was the measurement. 250 PPM is max. My question is, what can i do to get the HC down to the max of 250? My motorhome has a chevy engine.
Answer:

Now this is only a well educated guess, and ultimately you will need a smog check repair station to verify this hands-on, but with HC measurements that high (700ppm) it seems your 1984 Fleetwood Southwind is suffering a misfire; more then likely due to the ignition system. A misfire means your motorhome's engine is not igniting all cylinders at the right time or thoroughly enough. This is resulting in the production of high unburned fuel (HC), and partially burned fuel (CO). Once the high HC fault is found and fixed, CO should drop dramatically as well. Begin by inspecting all the sparkplugs and their wires. If any of the plugs look worn out or have excessive carbon build-up replace them immediately. You may use any brand of product designed to work in your vehicle. The distributor cap should also be inspected for cracks or excessive carbon deposits. If it appears that the cap may be faulty, you will need to replace it. More then likely you will see an instant performance increase and a drop in HC once these corrections are made. posted by SmogTips Support

Related questions and answers you might find useful:

How Do I Get a Smog Check Waiver? by Margaret

Do I Need a Smog Check This Year? by Joy

Mini Cooper DMV Registration Due in 5 Day Won't Pass Smog by anne

2001 Jeep Grand Cherokee Laredo with K&N Air Filter by David

1995 BMW M3 Gross Polluter High HC & NO @ 15MPH by Jared

View SmogTips.com in: Desktop / Mobile