Emission Related ?

[MilTownSHO]

Took the 92 to emissions today, the first time it was within 10% of passing, the second time, it bombed. It failed on HC and NOx. My question is, can a stuck thermostat and faulty CID cause this? Both will be replaced this weekend. So HOPEFULLY it will pass.

 

[rangerj]

Miltownsho,

If you do not know whether the thermostat and/or the CID sensor are faulty, why are you replacing them? Have you tested them?

Check for codes stored in the computer and/or active codes. See my post to Betty Davis wjth in the last 15 days. It will delineate the tests for the EEC and components including the CID, CPS, DIS, and Coil pack.

Save yourself some money. Do the diagnostics before replacing parts.

If the thermostat is three years old or older go ahead and replace it. As for the sensors, test them first, or at least check to see if the codes are consistant with a failed sensor. rangerj

 

[MilTownSHO]

I'm sorry I worded that bad, I do know that both of those are bad. I was reading your post to her earlier today actually. I was just wondering if those items could cause a failure.

 

[projectSHO89]

A stuck thermostat will keep the engine from reaching proper operating temperature. That means the engine will likely remain in its closed-loop warm-up mode, meaning high emissions.

A faulty CID sensor is not likely to have any effect on emissions.

Steve

 

[sdpatt]

Try this techincal description of the conditions that allow the formation of high levels of emissions components.