GolfmanSpeck

So i got the code P1151, which means lean fuel mixture reading in the upstream bank to O2 sensor. So I checked it out and yes it is not functioning properly. My question is, the car has 127k miles on it and I don't believe it has ever had the O2s replaced, should I do them all (i don't really feel like shelling out $250-300 now) or can I replace them as they go out? Or maybe just the upstream 2?

BigTurbo6

How many do we have and how much do they cost!!! I'm used to only shelling out like $35 for an O2 sensor....and I think mine are getting old!! Is there a better brand? And how hard are they to get to?

8banger

Usually 4 and all are heated o2 sensors that cost around 120.00 apiece..
I'd just replace the one...or at the mostboth upstream o2's...IMO

GolfmanSpeck

I just bought two upstreams from bosch at 61.99 a piece, you can get them from ford for 89.99 a piece. They downstreams are easy, but I would invest in a O2 socket (about $14) for a 1/2in wrench. For me it was the only way I could get the front drivers side off. Also, if you don't have any get some mechanics gloves because you will probably have to heat theexhaustup first to get the O2 sensors off.

cliffyk

The Bosch 13275 is OEM for a 1988 Dodge Dynasty and generally costs about $40 at your FLAPS, cut off the Dodge connector and hook it up with good quality but splices--the wire colors are the same as the Forst OEM sensors, 2 white wires for the heater, a gray wire for the sensor ground, and a black wire for the sensor output. [/align][/align]All platinum/zirconia (narrow band) O2 sensors are electrically the same, the mounting is the only difference. The Bosch 13275has the same thread and lengththe same as the OEM Ford unit (and most Mazda's)--I just replaced the rear sensor's on my '03 GT with these when I installed a catted X-pipe.[/align][/align]

GolfmanSpeck

That would have been a good trick, maybe i will do that for the rear. About how often do you replace them. Bosch says that they are good for 100k, but i suppose it depends on the driving conditions.

cliffyk

O2 sensors will last 65k to 120k+, however the heaters sometimes fail sooner--on the front sensors failure of the heater will often cause problems before the engine is hot, or in low load stop & go driving, on the rear sensors the heaters are essential as generally the exhaust will be too cool back there to keep the sensor at 662°F (350°C) and they will not produce any output.[/align][/align]I have heard it said that the heaters in Bosch sensors fail sooner that those in other brands, however I have never experienced this in over 600k collective miles using them. The shortest period of time I've seen an O2 sensor last was about 25k miles (it was an NGK), the longest I've ever run one was over 180k miles.[/align][/align]An strongly overrich mixture will kill them quickly, as will a bad catalytic converter--also use of a non "sensor safe" RTV silicone sealer in the intake tract can kill them (although you would have to really gob the stuff on to the point that a fairly good quantity got sucked into the intake and burned). [/align][/align]You can check the heater by measuring it's current draw. They are generally 25W to 35W which translates to 1.9A to 2.7A at 12.6V when cold, this will drop a bit (to 1A to 1.8A) as the sensor heats up--sometimes even lower for a front or any sensor being well heated by the exhaust gasses.[/align][/align]The sensor itselfcan be very effectively bench tested [u=http://mymiata.paladinmicro.com/Miata4-WireO2.htm#O2SensorTesting] as described here[/url], although by the time I wrestle them out I will usually just slap in some new ones--the Bosch 13275 was less than $25 a couple/three years ago...[/align][/align]

Andrew00GT

i just went for an inspection and i failed immisions ... my O2 sensor was bad... i had them replace it and they said i need to drive it for about 200 miles for the computer to reset n then bring it back to pass... it was 150 for just the O2 .. not installed ... installed i payed 220