QuestionQUESTION: I have a 1990 Deville. I've checked the codes (had bad mpg and the car is running really rich of fuel) and found out that i needed a oxygen sensor among other things. The first week of Aug 07 I put a new oxygen sensor on the car, and it corrected the problem. I have noticed three weeks later the problem is back. If I idle my car for 3-4 minutes i can see gas on the ground where the tailpipe is. Is there more that I am missing? I think it is a computer problem at times because I can reset the computer and it will run like a dream, but 20-30 minutes later the computer catches up to me again. I got a tune up earlier this year, with new wires, plugs. I have put a new converter on, changed the oil every 2500 miles, transmission every 15k and changed the radiator fluid in 2/07. The car has 176k on it.
ANSWER: Are you POSITIVE that it is gas that is coming out of the tail pipe or just water from condensation. This IS very unusual as you would get a CHECK ENGINE light from the oxygen sensor indicating that the exhaust was running RICH.
If you put some of this tail pipe fluid on your finger does it smell just like gas ?.
The ONLY thing that would cause this would be:
Leaking fuel injectors which you could see dripping gas after the engine was stopped and the air cleaner was removed and you physically looked at the 2 fuel injectors to see if they are dripping gas into the engine.
A faulty ECM (computer) which is delivering to much gas to the engine due to an internal fault but again the CHECK ENGINE light would come ON and a RICH exhaust system would be indicated.
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QUESTION: I AM POSITIVE that there is gas coming from the exhaust. I have placed my hand down there a few different times and smelled a strong odor of gas. I have even moved my car from that area and rubbed my finger on the ground where the area is wet and it smells like gas also. I don't smell gas up in the engine area when the car is running, nor when it is stopped. When I fixed the Oxygen sensor and converter the problem stopped, but since 8/20/07 it's returned. THANKS.
ANSWER: OK, Let's see if you have any FAULT CODES in the computers via:
1. Ignition key ON. Engine OFF.
2. Simultaneously push and hold the OFF and WARMER buttons on your climate control panel for 3 seconds and release them.
3. Fault CODES will appear in the form of LETTERS and NUMBERS combined together on the fuel data display, Such as E38 or EE38 or any other letter number combination.
4. After all the codes display you will see .7.0 on the fuel data dispaly.
5. Write down these letter number combinations EXACTLY as they appear in the EXACT order as they display as if you were video taping them and let me know what you get.
6. Turn OFF ignition key.
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QUESTION: The codes are E31 E40 E52 //// EE: EE40 //// F: F:48 ending with 7.0
AnswerOK, The ones we are concerned about are EE40 and FF48.
EE40 = open power steering switch. Take a look at the passengers side of the power steering rack and you will see a 2 wire electrical harness connected to a pressure switch. Check the wires for any rubbing off of the insulation or damage and repair it. If you see no wire damage replace the pressure switch.
What this switch does is increase the engines rpm's when making tight turns at low speeds or at idle speed.
FF48 = Low refrigerant in AC system. Have the freon level checked and freon added if necessary.
I realize that these 2 codes have NOTHING to do with your gas problem but they need to be fixed so we can CLEAR (erase) the CODES from the computer in order to do other test procedures.
After you get the 2 codes fixed:
Redo steps ! thru 4 and when you see .7.0
Simultaneously push and hold the OFF and HI buttons on your climate control panel until you see E.0.0 and release the buttons.
Simultaneously push and hold the OFF and LO buttons on your climate control panel until you see F.0.0 and release the buttons.
Press and release AUTO button and turn OFF ignition key.
You can CLEAR the codes NOW if you wish and then repeat steps 1 thru 4, But codes EE40 and FF48 will most likely return.
There are 8 fuel injectors on your vehicle, NOT 2, My apologies, I was thinking of a different year vehicle.
Your most likely cause is that some of the fuel injectors are leaking fuel into the engine after the engine is shut OFF. You will need to have the 8 injectors tested and have the faulty ones replaced.
