Hi All, I have a 2001 Taurus SE (3.0, OHV, 180.000 miles) and we are having trouble getting the car to start & run OK. A little history: Car fuel pump went out. Got a new pump & had a mobile mechanic come & change pump motor (just the pump motor-not the whole sending unit). Car started & ran fine after repair. Then had same mobile mechanic change out the A/C fan clutch pulley out (dropped sub-frame & changed pulley though wheel well). Again the car ran fine after the repair. Let the car sit a few weeks and then started car again to check trans fluid level. The car started & ran fine but tranny fluid bubbled out of trans fluid filler tube while I was looking at fluid level on trans fluid dipstick. Shut car off immediately. Car sat for a few weeks until I found info on the AX4S vent cap being pushed down/blocked that would cause the bubbling trans fluid out of filler tube. Found tranny vent and cleaned vent & replaced the cap. Tried to start car/battery dead. Jumped battery & car would turn over but would not catch. Sprayed starting fluid up the intake & car would catch & run a for a moment. Kept spraying bursts of starting fluid & car would run for a few more moments, but would run rough (pop & backfire) then die. Changed out the fuel filter & after that the car would still start, and still run rough (popping & backfiring) and still would die after a few moments. Called another (different) mobile mechanic and we jump started the car when the 2 guys got here. Car would catch, run really rough (pops & backfiring) then die . They pulled codes & said it showed codes P1131 & P1151. Mechanic said that usually means O2 sensor codes, but could be a bunch of different things. Mechanics looked for any missing or broken vacuum hose or tube & couldn't find anything wrong. Then they checked for broken or disconnected electrical connector & found no trouble found. Mechanics checked the fuses & relays & said they are ok. Mechanic got fuel to come out of the schraeder valve so we know the fuel pump is working. They checked both O2 sensors on top & cleaned the O2 sensor closed to the front of the car. The mechanics said there is a 3rd O2 sensor & they checked to see if it was hooked up & it looked OK. They cleaned the MAF, and the IAC sensor. After all this, the car will start (jumping the battery) and will run rough (some popping/backfiring) for a minute or 2, and then die. Mobile mechanics spent almost 3 hours and couldn't get the car fixed or really even isolated the exact trouble. Their best guess is that the car catalytic converter or exhaust is clogged/blocked, or that the O2 sensors are bad, or that one or more of the fuel injectors went bad. Kind of bothers me they didn't check the fuel pressure on a guage, and that the code reader they had was a bottom of the line reader & could do little more than read the codes. I just don't understand how the car could run great after the fuel pump change, but now be having this trouble. My gut tells me the trouble is something simple, that maybe I knocked off a vacuum line or broke a wire when I was looking for the tranny vent cap but the two mechanics said everything is where it should be. I can't afford to spend money swapping parts out trying to find the trouble. Sorry for the long post but I wanted to make sure I gave all the pertinent info. This has been very frustrating and I appreciate everyone's help & advice

 

These codes indicate a LEAN condition in banks 1&2.

1) Clean your MAF and than disconnect your battery to reset your PCM. If the code(s) come back...

2) Do a search on the word "Lean". The posts will tell you to check for vacuum leaks. (unmetered air getting into your motor will cause a lean condition.)

If you need more help, don't hesitate to post again.

Good Luck

 

Thanks bluewind, the 2 mobile mechanics did check & clean the MAF sensor, and I purchased & installed a new car battery after that. Then I turned the door lock with the key just to make sure it wasn't a PATS anti-theft issue. I got my code reader out & I could not pull any codes at all like the 2 mobile mechanics said they did, but maybe I wasn't doing it correctly. Anyway, last night I went out to the car & was going to have my son make a little video to put on a youtube link so that folks could click on it to see/hear how the car sounds & runs (even though it was only running for a few moments). Unfortunately, when we got out there last night, the car, with a new battery, cranked over great, but it wouldn't catch/start at all. So, now we're back to a crank/no start condition. I haven't had a chance to do the search on the word "lean" yet, as you suggested, but I'm not sure what you meant by the color BLUE in your reply. I assume it is just a typo or has to due with trying to emphasize the vacumm/lean condition. Is that correct? Thanks again for all of your help & assistance-I do apprecite it!!

 

Don't worry about the "blue". I copied and pasted this answer and sometimes the format does get jumbled.

Actually, I don't have direct experience with P1131 & P1151, but I had P0171 which also means lean condition.

"lean" means there is either too much air or not enough fuel in the mixture.
Too much air means air that has not been measured by the MAF sensor. That means any vacuum leak between the MAF sensor and the intake at the head can cause this problem.
Too little fuel could be caused by the same problem and also by low fuel pressure.

So: low fuel pressure from a faulty pump or clogged filter, so you need to run a fuel pressure test to see if the pressure is low, below 26psi is to low. If the pressure is fine then you have a vacuum leak, which is very common on this model due to intake gaskets and isolator bolts which need to be replaced. Also check for a cracked or torn PCV tube.

If you have trouble with the isolator bolts it is actually trouble with the grommets on the isolator bolts. They shrink and get hard so they let air by. Replacing them is easy but time consuming.

 

Also : you never mentioned the ignition parts. They may need replacing. Plugs, wires, and maybe the coil pack.

 

Bluewind, I believe you gave some good advice and suggestions, but I'm puzzled by just what oldad is going to do. I don't know if he is going to tackle any of your suggestions or if he is going to have more people putting their fingers in there and making more problems than already present. It's difficult to make worthwhile suggestions not knowing what the other guys may have tampered with or screwed up.
I agree one of the first steps would be to confirm the integrity of the fuel system, keeping in mind because it was recently replaced doesn't mean its working as required. You can't keep jumping around hunting and poking hoping to find the problem(s) without some planned system/sequence. How do you guys feel about this?