what would cause your car to run rich?

Question

3100 V-6 GM motor multi port fuel injection

Answer 1

improper air/fuel mixture. Check air filter

Answer 2

There are lots of reason for a EFI car to start running rich and giving bad mileage (i.e. defective switches, sensors, etc). First of all you should replace all filters, plugs and wires, make a complete tune up (timing, belts, etc.) and get all 4 injectors cleaned at a service shop. Then check the AFM as the workshop manual. If the AFM is not working properly, then it will not measure the correct amount of air enetring the system, causing problems like over-rich mixture, bad mileage, hesitation and/or rough idle. O2 sensors works only during closed loop condition, so you should check it only when you fail emission test at idle. Any other off-idle condition is controlled by the maps programmed at the ECU.

A clogged pre-cat will restrict air flowing out of the engine and the main symptom would be boost drop. If you´re running rich then your main cat WILL get clogged because of carbon build up.

Answer 3

Burning High octane gas when your car is registered at 87 regular fuel. 3.1 L is no different than when I had a 95 camaro 3.4 L never go beyond adding 87 octane when the owners manual tells you. Stay with Valvoline Oil too, using a mixture of different oils and brands such as Synthetic and non Synthetic can cause your car to run like chit. These people above me, crack me up.....there is no carburetor's on a 3.1 L Fuel injection LOL haha

Answer 4

If it were my motor motorized vehicle i'd take it to a GM dealership and performance them hook up the Tech 2 diagnostic device on your computing gadget and see if it has any codes in it. Your service engine right away mushy does no longer would favor to be lit up on your motor motorized vehicle to have worry codes in it. they'd also be certain the air pass it quite is operating by your supercharger and see even if it quite is sufficient or no longer. interior the adventure that your transmission replaced into having themes your fluid would perchance be burnt (looking/smelling), have metallic shavings interior the pan, or your shift solenoids would set off off a worry code. i are conscious of it sucks distributing money to a GM dealership yet in certain situations it is your desirable guess.

Answer 5

Start with cheapest and easiest possibility first. Replace the air filter and see if the problem goes away. If it does, that was the reason. If not, search more, like get readout from computer.

Answer 6

this means too much fuel is reaching the combustion..

check you fuel injectors, throttle body, you know, things of that nature!

Answer 7

bad o2 sensor, bad mass flow sensor, leaky injectors, bad carb float?

listing the car you're having problems with might help.

Answer 8

Dirty air filter.
Faulty carburator.
Bad O2 sensor.
Stuck choke.

Answer 9

your carburetter needs adjusting and tuning.