97 GTS is running really rich, the gas smell is hard to tolerate in the car...

[ArlyDude]

I'm pretty sure the O2 sensor is going bad. There is no engine light on and it almost wants to stall when you come to a stop. I know it's running really rich but why is the question. I have B&B Headers and side exhaust with no cats. I did have a bad O2 sensor about 8 years and 10,000 miles ago, and the symptons were about the same but about 5 times worse then with the engine light on. It backfires a lot more now too when I let off the gas. If I'm not mistaken there is 1 O2 sensor and the other bank has a sim in it. I remember from the past I cannot put a Bosch O2 in because only the OEM one worked. Let me know your thoughts before I go ahead and buy and change it. Thanks!

 

[kratedisease]

Yes most likely the O2 sensor. I am told that that is one of the first offenders when it comes to tune of the engine. Your car should have two, one on each side... as I have been informed. ( I am not a mechanic)

 

[Tagoo]

You may want to check the the plug wires too. I had one pop off at the spark plug once. The difference when driving on only 9 cylinders was hardly noticable except that it sounded a bit odd and almost stalled when i came to a stop. I also noticed one of my side sills was noticeably hotter than the other side. I can't imagine what made the plug wire come off of the plug, but snapping it back on tightly put everything back to normal. Oh, Running on 9 cylinders did not set off a check engine light.

 

[v10enomous]

Lots of threads on fumes in GTS's. There are 3 local`s including me with no cats and we all find that you get fumes with the window(s) down. Not at all unusual.

 

[ArlyDude]

I had my car for 8 years, I know what normal gas fumes smell like and I know these were intolerable and I also notices, the wanting the stall at idle and rough idle when I pull out. There is an air/fuel mixing problem.

 

[speedracervr4]

The stalling/rough idle sounds more like a vacuum leak to me. You have 4 o2 sensors, but only the front two (bank 1, bank 2 in the headers) effect the tune.

 

[Hoosier Daddy]

If I'm not mistaken a 97 only has O2 sensors before the cats, none in the rear part of the exhaust. That nonsense started with the 98 model year. Almost sounds that you have a grounded spark plug wire or it is loose. Raw fuel is being dumped into the exhaust from one cylinder. If you had cats they would have become extremely hot burning up the raw fuel. I had a bad wire to one cylinder, that overheated one cat and started melting the plastic and sidesill area. Found this out when smoke started entering my car at a stop light.

 

[speedracervr4]

I thought any car after 96 required o2 sensors after the cats? For OBD2 emissions purposes..I might be wrong though.

 

[Jack B]

All the vipers have four O2 sensors, my Gen1 had four O2's. The back two monitor the condition of the cat.. It was not until 1999-2000 where the O2's started setting codes for high flow cats or cat deletion. They altered the delta (that sets a code) between the front and back O2's from that point on. There is nothing wrong with the Bosch sensors, I am running them in my car. In summary, the rear O2's in 1998 and older cars did virtually nothing and have no impact on the the overt operation of the car.

The front O2's are what controls the A/F ratio. In general if your a/f ratio is not in range the car will set a hard code, which means the CEL will illuminate. Pesonnally I would pull the battery cable to power down the car to reset the pcm. If it still has the gas odor after you reconnect the battery, find a good viper tech. As a point of interest, a bad ground connection in the O2 sensor circuit can cause the same issues.

If you truly have raw gs exiting the exhaust it can be dangerous, the cat can run so hot it can start a fire near the front of the door down by the sill or where the exhaust exits. By any chance does your car have a VEC.

 

[uvbnbit]

O2's can get "lazy" after a few years. If your sensors are in the 5 and 6 tubes, relocate to the collectors (may have, and I missed that). Helps big time. If 5/6 cylinders are "lean", computer will add fuel to all. (I've had B&B's, no cats for 6 yrs-put hi flows on 2 months ago)

 

[ArlyDude]

I have no VEC. Can someone please tell me what part numbers of the 2 O2 sencors I need to buy. I'm not sure if they are the upstream or the down. Thanks.

 

[speedracervr4]

Upstream. I don't know the part #, but Roe has them http://www.roeracing.com/ProductCart/pc/O2-Sensor-96-98-RT-10-GTS-Upstream-175p550.htm