Hard start when cold, running rich, poor fuel economy
3.3L, flex fuel, running gasoline. 77,000 miles. When it is below 40
degrees F, the car will not start normally. I have to put the pedal to
the floor to get it to start. Strong raw gas smell from exhaust. Engine
light was on, code said O2 sensor bank one. Replaced O2 sensor.(old one
was highly carboned). Replaced spark plugs. Cleaned intake. I'm getting
about 11MPG city whereas I used to normally get 17MPG. Once the car
warms fully up, it runs fine. Maybe some sort of air temp sensor is bad? Thanks
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Re: Hard start when cold, running rich, poor fuel economy
Chrysler has a bulletin out for a simular condititon that involves replacing the pcm. Heres the bulletin number 18-005-04. This is only 1 possible cause , Fuel pressure, coolant temp sensor, thottle position sensor all can cause like problems. Seeing sensor values and fuel adaptives with a scan tool helps pin point problems.
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Since batteries lose almost half their cranking power at freezing, and since diesels require much higher fuel temps to start than gasoline engines, many recommend using a block heater whenever the temperature is under 35-40 degrees if starting becomes a problem.
Yes it is. Problem is , ethanol eats up the rubber hoses and seals/O rings. Besides that, old engines will run on it. Just don't run it under 40 degrees outside temperature. Well not even the flex fuel cars either.
A Flex fuel vehicle is one which can use E85 Ethanol fuel. This fuel has 15% alcohol and is more corrosive than basic Gasohol. This is a newer name for using 2 types of gasoline. It does not apply to leaded fuels.
Flex fuel may also be vehicles using a compressed liquid gas and gasoline. These types use gasoline to start and switch automatically to the second fuel system. There were older names for these systems.
There are systems which operate strictly on compressed liquid gas. Hybrids are those using electric and gasoline.
I`m guessing you mean engine air filter not cabin air filter. the symptoms would be running rich, poor fuel economy, hard start if its badly plugged, having to push further on the gas pedal to get vehicle to move.
maybe a clogged filter.. why 2 months? it has old gas in it..gas does evaporate to a degree..looses some of its power creating capability.. the mtbe additive is an extreme evaporative.. it will evaporate out very quickly.. remember all fuel tanks have a vent tube on them..
I had the same problem on my 2001 Sunfire (same car as the Cavalier-different branding) which I was able to fix successfully.
My symptoms were:
-Traction Control OFF light illuminated
-Cooling fan running even if engine cold and it was freezing outside (I also noticed that when the Traction light illuminated, the fan would then begin)
-Rough idle with black smoke when cold
-Poor fuel economy
I have a code reader which produced codes P0130 and P0171. These are error codes for the upstream oxygen sensor (the one under the hood).
I simply replaced the O2 sensor (it took me 10 minutes). I did not reset the check engine light after the repair as I wanted to see what the car would do on its own. The idle was much smoother with no smoke and the cooling fan stopped running unnecessarily. After 1/2 mile down the road, the Trac light went away and the system functioned normally. I tested this by trying to accelerate quickly up a snowy driveway. I also noticed that the acceleration and shifting (auto tranny) were smoother. I reset the check engine light. All is satisfactory.
What was happening to the car before the repair:
P0130 is usually for a bad O2 sensor and P0171 is the sensor detected that the motor was running too lean (but it actually wasn't-the sensor was essentially giving a false lean signal).
The rough idle, black smoke, and poor economy are due to running too rich. In my case, the sensor told the PCM (the car's computer) that the air/fuel mixture was too lean. In response, the computer said "OK, more gas!" That's why it ran rich. This was evidenced on the old O2 sensor as well...it was completely caked with carbon from an excessively rich mixture. This further destroyed the performance of the O2 sensor.
Ask your local technician to set up a fuel gauge pressure monitor so you can track it while your driving. Ask him what the normal range is so you will know when it falls below. Document it and let your
Tech know. It sounds like your fuel pump is loosing
Have a fuel pressure leak down test run on the fuel pump. This is a symptom of the electric pump pressure check valve being defective, the valve is part of the fuel pump and it is mounted in the fuel tank. Also make sure you are using 87 Octane gasoline, higher octanes can cause stall issues on cold starts.