Emissions Test Problem

[vanionBB]

First off, I searched the crap out of this and couldnt find an answer so I am asking, if I missed a thread please let me know

Today I went to the DMV and tried to get the required emissions test for my vehicle. I have a 1996 Explorer LTD with a 4.0L OHV engine. After the test was finished the guy says that my explorer was unable to complete the test due to:

Catalyst Monitor (not completed)
O2 Sensor Heater (not completed)
O2 Sensor (not completed)

I did drive the truck for over 20 miles on the freeway and on side roads, and let it idle. Total drive time was over an hour. It was warmed up.

I did just replace the alternator and the KAM was erased I think but after driving it all over the place it should have been enough for the computer to get enough data I thought. How much more should I drive it before testing it again? Is there a way to know when I have driven enough, will something blink at me on the dash?

I cannot afford to fail again

Thanks in advance for any help, this forum has been my new home for over a week now. I feel like I know you all after reading so many posts.

 

[vanionBB]

Actually just read somewhere that the catalyst monitor is the one behind the catalytic converter to monitor cat efficiency. I just replaced that one with a brand new one because the old one broke off (mechanic dropped the tranny and ripped the electronics out). The other 2 are stock as far as I know, probably could use changing, but if the computer doesnt even register them, then what??

If they were bad or broken, the computer would spit out a code I think. What does no code but not completed mean?

 

[vanionBB]

Hi, thanks for all the help!

To update yall, I drove the truck today by the book. In the owners manual it describes step by step what to do to reset the comptuer and make sure the sensors are all functional. I did this, it took about 45 minutes of driving, stopping, starting, etc. I went to the emissions place just in time and FAILED again, but there is a catch to that.

The o2 sensors all functioned correctly, and everything checked out. I only had one error, and that was the Check Engine light was malfunctioning. THE FREAKING LIGHT!!! For some reason the previous owner disconnected the Check Engine light... The emissions place was closing and told me to come back on monday with the light fixed.

Now I have to tear down the dash and find the bulb or the wire leading to it and fix it. At least the rest of the truck passed, so now I can get tabs. This is a big load off my shoulders.

Side note, the customer service at the emissions place was terrible. I had it checked at the Bellevue WA emissions place near eastgate, and the guy had this huge attitude problem. He was very short with me, and wouldnt let me ask any questions until he was finished talking. Very annoying, but at least it is done.

Thanks again for all the help, even though nobody posted, I did learn alot from searching threads.

 

[Blee1099]

The truck is probably throwing some OBDII codes. If you have an Autozone close by, take it over there and ask them to scan the truck for codes.

 

[vanionBB]

I replaced the Check Engine Light bulb. The previous owner removed the metal tabs on the bulb, presumably to turn off the CEL so he could sell it. After replacing the bulb, I PASSED EMISSIONS!!!!

Soon after the test, CEL started throwing codes... (but at least I have tabs!!!)

First code was the catalytic converter, P0420. Next it was code P0133, O2 sensor bank 1 sensor 1. I just replaced one of those sensors before the cat, cant remember which side. Is the Bank 1 Sensor 1 before the cat or after it?

Anyway, test passed so that is done. Now to track down why I am getting O2 sensor codes...

One note, the cat is over 200,000 miles I am sure, also the O2 sensors are probably in the same boat. Is it time to replace them all? Also the truck had a nasty engine before and the exhaust pipes are pretty skuzzy. Is it time to just replace the whole thing, pipes and all, or is there a cheap place to get o2 sensors, or can they be cleaned?

Sorry so many questions, I will do some searches

Thanks again for all the infos!

Cheers!

 

[ma96782]

With the vehicle over the 200K mile mark......IMHO......I'd replace the sensors.

Aloha, Mark