Contour Enthusiasts Group Archives Forums Modifications Zetec Maintenance I'm Lost (P1131 - P0171) ?? Car Shutting Off!!

I've been searching all day, but nothing is making since. A few days ago I noticed that my car has been burning more gas than normal. I get about 250 miles rather than 285 per fillup. So I checked it with my scanner and the code P0171 was there. I thought maybe that was because of Auto Shop that cleaned out my Intakes as they had to remove so parts to get down in there. So Anyway I cleared the Error and now the old P1131 comes back. I checked the MAF and it's clean. Some times when the car is at idle it likes to rev fine and then when the fans come on it idels to low at around 500rpms. It likes to do this alot.

Mercury Mystique 98 2.0L 4Cyl, has over a 100K miles.

Now for the last month or 2 I've been running into another problem. On very hot days the car has been shutting off while driving. The first time was right after my wife got back from driving around all day. I checked the oil and it was very low. So I filled it up and drove to work just fine. I got an oil change the next day and it's been fine for about 2000 miles. Now today after she was driving around it shut off a few times again. I checked the oil and it was just below the bottem nitch on the dip stick. I filled it up and drove to work just fine. There is only an oil light on once the car has stalled in the middle of the road. I just turn it off and back on and she goes again.

Do these cars shut off the car if the oil is low or there is a heat problem? If I'm losing oil I don't smell or see it, so I'm lost here? I replaced the gasket seal last year.

You would think the car would have a code for this. But the only code I keep seeing now is the P1131. I do have the VCT problem, but just have not got around to getting that fixed...lol

Where is that senser located at? Is it the one right next to the MAF but just under that organ house intake? If so what part is this and were can I get one cheap?

Oh and the Oil problem.. Where would that be leaking?

Just putting this here for me to read later.

http://www.thedieselstop.com/faq/9497faq/tsb/tsb/files/010907.pdf

o2 and clean MAF.

I think the other code was just from the superlube messing with my system because it does not come back. However the P1131 comes back after every drive when I reset it with my scanner.

Where is this O2 that I should be looking for? This Haynes book shows all of the sensors, but they don't list the same stuff so it's confusing me. The haynes manual shows only one oxygen sensor at the front of the engine?

My scanner says, "P1131 Fuel Air Metering."

Okay.. I did find this info.

"P1131 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1.


The O2 simply unscrews from the exhaust manifold between the engine and the radiator.

Since this engine only has one O2 for fuel metering, there is no simple way to tell if the O2 is bad or if there is another problem affecting the mixture.

Standard procedure for this code would mean cleaning the MAF, looking for vacuum leaks, and changing the O2.

The CEL will come and go as the running conditions change."

Hmmm.. so I'm looking for a part in the front of the engine?
I need part numbers so I can replace it!

Does this look like the part?

That's it.