[benjarrett]

I know that lean burn mode is greatly affected by load, road, speed, environment etc. But I notice that if driving around 65mph on a flat road with no head wind on an average temperature day (70) that my insight will run for about 1 minute in lean burn, then kick out for 10-12 seconds and then back for a minute of lean burn etc. Have you guys had a similar experience? Is this normal?

 

[HafNHaf]

thats normal operation, although only one minute of lean burn sounds like you are on the ragged edge of the lean burn window. try 60 mph on the same route and see if it stays in l/b longer. btw, the drop out of l/b is to purge the NOx cat converter.

see:

http://www.insightcentral.net/encyclope ... lytic.html

 

[Rick]

This is a completely normal NOX purge, it does this for emissions reasons. If traffic allows just keep your foot planted and in a few seconds it will return to exactly where you had it before. The only thing is you'll get a little surge of power when it drops in to stoich burn so be sure there isn't anyone too close in front of you.

Alternately you can simply back off the pedal, but this will end up making the purge take a little bit longer to complete.

 

[benjarrett]

Thanks for your answers guys. I just wanted to make sure my NOx purge was occurring normally. Last night I was able to stay in lean burn much longer by staying around 60 rather than 65mph. Speed makes a difference. I wonder, if the cycle of lean burn decreases overall, does that indicate a problem beginning with the NOx catalytic converter?

 

[Rick]

No I think it has more to do with volume of gas flowing through it.

 

[Insightful Trekker]

AFAIK and since the Insight is not equipped with a NOx sensor the ECM/PCM is mapped with the data of these engine emissions. Under various load, speed, and temperature conditions a certian amount of NOx ocurrs. With the greatest quantities happning during lean burn. NOx purge is then cycled accordingly.

HTH!

 

[tuna1]

Lean Burn,NOx perge cycle,3rd O2 in 2003 MY

A 3rd O2 sensor,downstream of the NOx coveter was added in the 2003 model year to the engine control system to monitor the NOx perge cycle,and that was also the recall for the early year Insights to improve the emission control with a new upgraded ECM (and the increased cat failure rate after the upgraded ECM were installed).The O2 sensors for the 2003 model year on are different from the early cars,by nature of the different control system used.Honda has been improving the engine control over the years.