What does it mean when I'm told that my air / fuel mix is too rich ?

Question

Does that mean the carbureator needs adjusted? And how does it need adjusted ? I am asking because that is what I found online in explanantion of a fuel fouled spark plug. OR is it something else ?

2001 Dodge Ram 8 cylinder 5.9L
2 plugs fouled

as far as gas goes we are in CA but only run chevron 87 in it. not sure if chevron still using mtbes or not

Answer 1

Go with the cheap and easy fix first. First check the air system. Check the air filter, and related air flow passages. If you are wrong, you can use a new air filter later. If you are right, then you saved yourself a lot of time and money.
Next worry about other things. It could be the fuel injector or carb, whichever is appropriate. It could be a sensor. It could be a computer glitch. Again, start with the obvious. Then start with the cheapest. Then go with the easiest. As you gather information you can narrow the list of possible causes. If you do not have the expertise to do this, then go to a mechanic. Hopefully he will look at your air filter BEFORE hooking up a diagnostic machine.

Answer 2

I am not sure what kind of car you have or anything, but possibly what he is trying to tell you is that the heated oxygen sensor is bad. This is not an uncommon problem, a heated oxygen sensor is designed to heat the oxygen sensor faster than the exhaust would normally do so that the emissions can be controlled by the computer faster. An oxygen sensor doesn't work until it gets up to approx 500 degrees. As far as a lean condition, this can be caused by a vacuum leak. I have never seen a lean condition caused by a bad thermostat. Now the intake gasket may be the source of the vacuum leak but I would take it to a different tech and get another opinion. If this is a GM vehicle with a 3.1 or 3.4 engine, then they are notorious for having bad intake gaskets. If this is what you have and the intake is leaking, request that they replace it with a steel fel-pro intake set. Plastic, which everyone else makes, lasts about as long as the original. Go steel.

Answer 3

Sometime the problem is not to much fuel but not enough air. If the air cleaner is blocked the mixture will become richer as theres less air to vapourise the fuel in the carbureator or injection. Try removing the air filter/cleaner and change or clean it and check again. You can run with out an air cleaner fora short period just to check, but not for days.

Answer 4

You need to get it hooked up on a computer and have it checked out. It could be bad injector, leaking intake manifold (making sensor "read" that mix it too lean), - and causing it to put in too much - to try and solve the problem. Or it could be something else that isn't normally associated with this kind of problem Start with computer diagnostic, - followed with a mechanic that has a lot of experience with this sort of problem before. Believe it or not some mechanics are smarter than computers!!

Answer 5

In internal combustion engines, the air-fuel ratio refers to the proportion of air and fuel present during combustion. The chemically optimal point at which this happens is the stoichiometric ratio (sometimes referred to as stoich), where all the fuel and all the oxygen content in the air of the combustion chamber will perfectly balance each other out during combustion.

For gasoline fuel, the stoichiometric air/fuel mixture is approximately 14.7 times the mass of air to fuel. This is the mixture that modern engine management systems employing fuel injection attempt to achieve in light load cruise situations. Any mixture less than 14.7 to 1 is considered to be a rich mixture, any more than 14.7 to 1 is a lean mixture -- given perfect (ideal) "test" fuel (gasoline consisting of solely n-heptane and iso-octane). In reality, most fuels consist of a combination of heptane, octane, a handful of other -tanes, plus additives including detergents, and possibly oygenators such as MTBE (Methyl tert-butyl ether) or ethanol/methanol. These compounds all alter the stoichiometric ratio, with most of the additives pushing the ratio downward (oxygenators bring extra oxygen to the combustion event in liquid form that is released at time of combustions; for MTBE-laden fuel, a stoichiometric ratio can be as low as 14.1:1). Vehicles using an oxygen sensor(s) or other feedback-loop to control fuel to air ratios (usually by controlling fuel volume) will usually compensate automatically for this change in the fuel's stoichiometric rate by measuring the exhaust gas composition, while vehicles without such controls (such as most motorcycles, and cars predating the mid-1970's) may have difficulties running certain botique blends of fuels (esp. winter fuels used in some areas) and may need to be rejetted (or otherwise have the fueling ratios altered) to compensate for special botique fuel mixes.

Answer 6

Unless you have a really old car, you won't have a carb, it means that you are getting too much gas, not enough air, but with today's fuel injection, it is not an easy fix.

Answer 7

this vehicle has a lot of transmission problems, not related to your problem likely, but something to look forward to
http://www.minerich.com/dodge_ram.htm

All I could find on the RICH problem, not much help I'm afraid
http://www.dodgeforum.com/m_126804/mpage_1/key_/tm.htm

buy a SUBARU

Answer 8

You have too much fuel and not enough air. You need to adjust your carburetor.

Answer 9

there are fuel mixture screws on your carb, turn out or in 1/2 turn,
i forgot which, auto repair manual will tell you, or auto parts storre etc.
they'll be glad to help

Answer 10

more info - what year what engine, one plug fouled or all of them, any other problems...etc