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Completely confused about problem

Old 01-18-2009, 09:48 PM
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Join Date: Jan 2009
Location: United States
Posts: 1

<DIV id=post_message_1574917>Hey all... I''m new here, and I''m looking forward to meeting you all, and learning from you. With that being said, here''s the issue(s) (Sorry if it gets a bit long winded...)

My wife''s 99 cougar has been acting up lately. I guess that this has been going on for some time, but she neglected to tell me (I guess she thinks I''m Kreskin and I was supposed to just know it was an issue). Anyways, It''s gotten really bad in the past 3 days, when the temperature here dropped well below 0 degrees. The car seemes to start ok, and the RPMs goes up to about 1000, then it falters and stalls out, unless I keep my foot on the gas. When it stalls out, the whole car vibrates very badly. Her check engine light was on (and has been for about 2 years now), so I took my code reader and she had 14 errors. Here''s the errors...
P1507 - IAC Underspeed Error
p0156 - HO2S Sensor Circuit Malfunction
p0402 - EGR Flow Excessive Detected
p1401 - DPF EGR Sensor Circuit High Voltage Detected
p1131 - lack of HO2S- switch
p1151 - lack of HO2S- switch
p0301-p0306 - cylinder 1-6 misfire
p0171 - Bank 1 too lean
p0174 - Bank 2 too lean

I erased the above codes so that I''d know what I had to start with.

I called a friend of mine and he in turned called a friend who used to work on fords/mercury''s, and he said to check my Vacuum Advance Tube. Well, in the process of trying to figure out how to disconnect it from the boot after the MAF, I broke the flexible tube, so i went to the nearest Autoparts store and got a piece of tubing. My friend told me to plug up that tube and when I did that, the car seemed to respond back to normal. All indications pointed to some sort of a vacuum leak, since when the brakes are applied it took a little longer to stall out. After stubby-ing in a piece of hose, I still have the problem. Another friend suggested it might be a fuel pump, fuel filter, or maybe some gumming up of the gas lines since she has to park in the street and the fuel lines are setting up against the snow. So earlier today I changed the fuel filter. I was suprised that there was very little gas that spilled out as I installed the new one. This seemed to help the idle and it also seemed to keep the car from stalling out. I also added a can of heet and a fuel injector cleaner in the gas tank. The car has 64K miles, so i figured that it was time for new plugs. After changing out the plugs, the idle seemed to be worse. I seemed to be getting some backfires while keeping my foot on the gas and again when the car stalled out. I listened for any vacuum leaks in the engine compartment, and i didn''t hear any. I did however hear a very repetitious noise that seemed to coincide with the white markings on the timing belt as it rotated, but that could be nothing. I also bled the brakes in the car, as she said they were getting "spongy" and she had a hard time stopping about 75% of the time. I did not notice any air bubbles in the fluid as I was bleeding the brakes. I also noticed a smell similar to burning plastic or rubber, and there is a big hesitation when pressing on the gas from idle. After letting the car run for about 3-4 minutes, the Check Engine Light came on, and I read the code again. This time it was P0300 (Random multiple Cylinder Misfire). I quintuple checked that I had all the spark plug wires in the correct positions. Although I did the plugs one at a time so I wouldn''t get them mixed up.

So here''s what I gathered from different forums for possible causes. Please tell me which ones I should just disregard as gobbledy-gook and which ones have some merit...

1. Fuel Pump (Title says it''s a 99, but door tag says it was built on 6/10/98, so I''m not sure if the recall would apply.)

2. EGR valve stuck open and/or EGR solenoid valve clogged (most likely by the foam gasket)

3. Bad Idle Air Control Valve

4. Bad Differential Pressure Feedback EGR (DPFE)

5. leak in vacuum hose somewhere in engine compartment

6. Plugged/Semi-plugged Fuel line

7. Air inlet plugged (I assume they meant somewhere after the MAF)

I''ve done a lot of searching on several forums, and it seems that several people are having similar problems. However, it seems that everyone has a different answer for fixing the problem.

Please leave your comments or send me a PM on your thoughts, or if you have another idea. (Telling me I''m a complete moron is acceptable... lol )

Thanks! </DIV>
Old 01-19-2009, 09:19 PM
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Join Date: Oct 2008
Location: United States
Posts: 1,361

I would double check the gap on those plugs. if you made the gap too large, it will have lots of trouble. I would definitely bet on a vacuum leak somewhere. check all vacuum lines and check valves. if a check valve allows any back flow, replace it. I doubt very much that there''s a air flow problem. that would give too rich codes. since you have too lean codes, it means there''s not enough fuel. though the fuel filter change may have remedied that one. There''s a lot of stuff to check. You may have to break down and let a mechanic look it over.

And keep the communication with your wife often and meaningful. Also, remind her that men don''t read minds, manuals, or changes in demeanor very well, if at all. My wife knows this and keeps me well informed on the issues with the crown vic she drives. Helps me keep it in top shape. If she didn''t tell me when it was giving her problems, we''d be out a lot more money than just the few things that have needed to be fixed so far.
Old 01-19-2009, 09:22 PM
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Join Date: Oct 2008
Location: United States
Posts: 1,361

also, recalls are for model years, not actual years. if the title says it''s a 99, then it''s a 99, no matter when it was built. take it to a dealer and get the recall taken care of. it should be free, if they won''t honor it, take it somewhere else. (you should probably call around first)
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