Running Rich

[underdog1924]

My car is running rich and need options on how to fix it. I'm am looking into a new thermostat since this may be the cause. Also since the radiator hoses are getting soft and need to be replaced might as well do the thermostat at the same time. The plugs and wires are ok and will be changed at the next 60k tune up. Is there anything else I can do to try and fix this? Thanks

 

[AutoXSHO]

How do you know your car is running rich?

As mentioned in another post, the car will run rich if it's not fully warming up. The thermostat is cheap and easy, and if it's questionable I'd just replace it. It is a maintenance item anyway. Have you cleaned the MAF sensor? Is the air filter clean?

JV

 

[underdog1924]

I think it's running rich because my tail pipes are extremely black, to go along with the rear end, you can smell it when standing next to it and it sucks gas like there's no tomorrow. I haven't checked the MAF, but the air filter is relatively clean. I may get a cheap air filter to hold me over till I get my new MAF and K&N cone.

 

[sdpatt]

If your car is warming up to the NORMAL temperature range and the O2 sensors are working okay, you can't be running rich - the EEC would adjust the fuel to compensate. If the EEC couldn't compensate for another problem and the mixture was actually rich, you would be seeing a CHECK ENGINE light to warn you of the rich mixture. Now if your O2 sensors are old and tired and not switching quickly enough, you could have a very slightly rich condition. When you burn hydrocarbon fuel you create water and carbon dioxide. Sometimes, usually in the colder weather, the carbon can show up on the exhaust piping. This does not mean your car is running rich. You may also be burning a little oil and this would create black soot around the exhaust tips.

 

[underdog1924]

I have new O2 sensors in there. The black pipes have been going on since the summer. The temp is usually low, around the line to the L in Normal at the highest. And the CE light hasn't come on in a while. My car is eating so much gas it's ridiculous. I've tried everything I can think of to help this but to no avail. I need to change the radiator hoses so I'll do the thermostat anyways while I'm there. The only thing left that I can think of is to change the plugs and wires which I want to wait until the next 60k tune up. Right now I'm getting around 200 miles per 3/4 tank. I used to be able to get 240-260 miles per 3/4 tank. Arrghh it's really driving me crazy!!!!!

 

[Mark in PDX]

Hey,
I am running into the same problem with my SHO- What did you do to fix your problem??

 

[heath94]

A new thermastat cured most of my car fuel gobbling problem, milage is much better -- now about my right foot

Gotta love those secondaries!!

 

[91 SHOplus]

Way to bring back an old thread! thumbs_u

 

[underdog1924]

New tstat fixed the deal. It's cheap and easy, so I would try that.

Sheesh, I saw I had an email saying someone had replied to this. I hadn't started a thread in who knows how long. Thought a ghost was around.

 

[rendyx]

A new t-stat will work wonders for the temp gauge too. My SHO now warms up in minutes, and it always takes about the same amount of time. I always thought the cold weather was keeping it on "C" for so long - was I ever wrong!

 

[yamahaSHO]

Have you tried the ETC? A bad ETC will make the car run horribly rich.

<small>[ March 06, 2003, 08:10 PM: Message edited by: yamahaSHO ]</small>

 

[Detenator]

HOw can you tell if the thermostat is bad?

 

[stevetatro]

Well, a lot of people just replace when they *think* it's bad. It's a really cheap part, and should be considered routine maintenance.

Or, you could remove yours, put it in a pan of water on the stove, heat the water, keep it in there until the t-stat opens, and at that point measure the temperature of the water. This should be in the 180-192 range (assuming you have a 180 or 192 t-stat).

 

[Detenator]

rendyx Says that the temp guage dwels on cold for a long time and takes for ever to warm up... wouldn't that lead me to believe that his 'stat is stuck on open instead of stuck on closed?

 

[Detenator]

I drove my car accross VT the other day from NH to Albany NY. This was about 11:00 at night, and the 'outside temp' button showed temperatures below 20. The lowest it dipped down was 4. NOw the thing is, the temp guage on the car had trouble keeping above normal, and remember, this is on a hilly road, with many twists and turns, and the car was going about 40-55 with frequent acceleration and breaking when the road wound through the small towns. This type of driving would put the temp guage above what it usualy goes, not below. The reason i ask is, if the thermostat is bad on my car, wouldn't it be the type that gets stuck open when it goes bad, and in 4 degree weather, wouldn't it deffinately close up?