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Discussion Starter #1
I'm in Chicago and took my 2005 GS to get the emissions test done on 2 consecutive days last week and failed both times. The temp outside was 31 and 27 degree F on the respective days. The first day, I was stuck in traffic (so I felt the engine was not hot enough), but I was able to put on about 20 highways miles before I went on the following day.

There is no CEL on. The only mod that has been done is adding the QuickSilver SS mufflers. 23K miles.

The onboard diagnostic system check revealed the following:

OBD malfunction indicator light status: OFF
Stored diagnotic trouble codes: NONE

Catalytic converter EFT: Not Ready
Secondary Air System: Not Ready
Oxygen Sensor: Not Ready

Comprensive component: Ready
Engine misfire: Ready
Evaporative Control System: Ready
Heated Oxygen Sensor: Ready
Fuel System Performance: Ready

Is this issue most like due to the car not being driven enough in the cold weather (I have rad that the system is on a closed loop and it takes a while for the systems to turn on). My registration is due by March, and with winter apporaching, I wont be driving the car all that often. Confused right now as to what to do...help appreciated!
 

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Catalytic converter EFT: Not Ready
Secondary Air System: Not Ready
Oxygen Sensor: Not Ready

Sounds like the engine has not heated up the Catalytic, the o2 sensor (A) before the cat gets a reading, then the other o2 sensor (B) get another reading after the cat. The reading from A should be higer from B provided the cat is up to temp.

As you had driven 20 miles or so, i'm thinking that the water termo may not be closing off. The defult position is open. When cold, it should be closed so that hot/warm water does not get cooled by the heat exchanger (radiator) As the engine heats up, and the water too, (normally about 195F or about 97C) the termo valve opens allowing water to be passed into the heat exchanger and cooled water into the engine.

I'm thinking that your car can't heat up due to this or, temp sensor at the cat is faulty, check some wires and stuff first. Good Luck
 

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Discussion Starter #3
Would this be something that the dealership could try and figure out fairly straightforward and remedy the situation without a significant cost?
 

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I can't speak to Maseratis specifically, but most cars with O2 systems etc. run in "open loop" mode when they're cold, meaning the fuel mixture, etc. are chosen from a preset table based on RPM. The engine computer watches various temp sensors and others to determine when the car is at normal operating temperature and then switches to "closed loop" mode where it uses the O2 sensor and others to dynamically adjust the fuel/oxygen mixture and other elements to yield the most efficient burn of the fuel. If one of the temp sensors has failed, or the radiator thermostat was stuck open as described above, or you simply didn't run the car long enough to bring it up to temp, you would see results similar to those described. I would think that a dealer's diagnostic machine would detect sensor failures with a brand-specific code (not necessarily something that would show up on a generic OBDII reader).

An air leak ahead of the CAT and O2 sensor could also cause similar symptoms.

Every thermostat I've seen is closed when cold. You can remove it and visually inspect that it is closed. The way to test that a thermostat opens as expected is to remove it from the vehicle and put it in a pot of water on the stove which you gradually heat to boiling. Somewhere before boiling, it should open. Typical thermostats open at 180-200F. For a "normal" car, it's almost easier to just replace the thermostat without even bothering to test it. They cost around $10-20. For a Maserati, that's probably a $300 part that has to be carried by hand from Italy :).
 

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It also maybe the Inlet Air Temp Sensor or IAT that is fault normally located just after the air box / air filter..... and the result is very rich fuel mixture.... like at start up. When you drove the car 20miles or so, did the temp reading on the dash go up to about 1/2 way? 200F? There is also a sending unit near the temp valve that sends temp readings to the ECU. Did the car seem under powered? When did you last change your spark plugs.

Note, if there is a air leak between the IAT and butterfly, you would run lean. The engin revs easy and fast but lack of fuel will cause loss power. OBD would pick this up.

As there is no such reading, I'm thinking take a close look at Temp sending unit and IAT first. If all is ok, let the car idle for 15mins and check if temp goes up. If it does, then maybe it's the temp sensor at the cat. If it does not heat up to 195 - 200F it is the temp valve.

Good luck
 

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Discussion Starter #6
The temp gage on the console does in fact read @ 200 F when it wamrs up and there does not seem to be any loss of power. The temp sensor in the CAT sounds likely. I'm going to give Lake Forest Sports Cars a call tomor and see what they say.
 

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Had the car been sitting for quite a while before you went in for the test? Had the battery died? If everything is working correctly a good 30miles of driving (city/hwy) will allow the computer to set the readiness monitors.
 

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I had the same problem when I got my car. It had been sitting for a few weeks before the inspection. It failed. I then drove my car for 50 miles hwy. I took it up to 110 mph then drove it straight to the shop. I kept the engine on until they were able to hook it up. It passed after that.
 

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I had the same problem. My mechanic said to "drive the hell out of it on the freeway" for at least 1 hour before coming in for emissions. Apparently all Maseratis and 993 Porsches have this issue. Worked like a charm. I passed with no problems.
 

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Discussion Starter #12
"Drive the hell out of it"...I love it! I only hope come spring, I don't have to tell a cop that pulls me over that was the advice from the mechanic.

With the weather here so spotty in Chicago, I was able to contact the Dept of Transport and have my emissions due date pushed back to my liking..I choose May.
 

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I drove about 100 highway miles yesterday and went in for the inspection and failed again! Same story:

Catalytic converter EFT: Not Ready
Secondary Air System: Not Ready
Oxygen Sensor: Not Ready

I guess I'll try again next week. Any other suggestions out there???
 

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When all else fails, offer a bribe.
 

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Move to a more libertarian state - or set up a trust to own the car in that state and register it there. :)
 

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FWIW on my GranTurismo I followed the instruction from Maserati service (and other wise web tips) to clear the Secondary Air System status after my (used) car was delivered: drive about 500 miles. It did the trick. I checked the status using an OBD reader and my iPhone every day for about 2 weeks, and it eventually turned to Ready :)
So I was able to pass smog check (in Northern California) yesterday.
 
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