It failed the Nitric Oxide 50/15 test with a 1674 reading on a 1045 allowed. While taking my emissions my car also ran hot and started steaming. I have also been have stalling problems and firing back on take-off. Also, a lot of shaking and my RPM moves on its own when I first start my car. Any advice one what is causing these problems

 

The very first thing I would say is to get the overheating problem resolved, coolant leaks? stuck T-stat? fans inop?

High combustion temp will cause excess NOx.
Also the EGR ports plugged up if the engine is tested at mid range RPM, will cause the same problem.
Fresh spark plugs air filter and oil change will all help the emission levels.

 

I just replaced the spark plugs twice, had a oil change, and replaced the air filter.
I also just put a brand new fan on it in December.
Anything else?

 

when you say your car is steaming, where is the steam coming from? the engine bay? if so you probably have a coolant leak somewhere, check the coolant lines running from the radiator to engine for leaks.

Also, put your vehicle information in your signature so we know what your talkin about, sincethere is a difference between fixing a 91 accord and a 2008 accord

 

It is coming from the little plastic jar where you pour the water or antifreeze.

 

you have steam coming out of the overflow reservoir? have you checked the coolant level in the radiator?(while the engine is cold)

 

When your car started to overheat, did the cooling fans come on?

Try to identify the source of the leak. The plastic bottle may be cracked, or the hose going to it.

The thermostat could be stuck. Get a replacement from the Honda Dealership with this part.

Air in your coolant system can cause the idle to fluctuate. Drain coolant, replace thermostat, refill at radiator while the bleeder valve on top of thermostat housing is open. Fill until a steady stream of coolant comes out of that valve. Close that valve. Top off radiator.

FITV or the IAC cause the idle to fluctuate. There is a thread about this in the DIY section.

For high NO emissions, plugged EGR ports are a common cause. Its a pretty simple DIY fix. Google search T2T013.pdf That document will has good instructions for the 94-97 accord at the end.

 

Oh, so NOW ya tell the whole story.........So what about the overheating problem?