PBiddy412

Hello all,

My current problem right now is that my check engine light is on and while the car is at idle, when warmed up, the rpms will jump up and down. I had this looked at and I was told the codes P1121 and P1131 were thrown and that it was the front two sensors on the car.

My grandfather and I were looking underneath and found where they were but have no clue on how to get to them. Trying to avoid paying for labor here if this is the case. Anyone know how to get to these or if there may be another problem here?

Thanks,
Patrick

Nitti00GT

My front two O2 sensors went bad shortly after getting my H-pipe installed so I took it back to the exhaust shop and they said that if I buy the O2 sensors they would put them in for free but they would have normally charged me 40 bucks to put both in. They said its a half hour of labor time. So you are looking at around 80 for the O2 sensors then about 40 for labor. You can do them yourself though. I haven't done O2s on a Mustang but I have done them before. Depending on where they are it might be easy or an extreme PTA.

PBiddy412

Well I have a 2002 Mustang GT. It does look like the front ones will be a PTA. I was hoping to be able to do it myself because around here people are estimating that it will be 80 for labor which is to much for me.

oxfordgt

Do you have any mods done to your car? With those code I would try cleaning the MAF before you go out and buy expensive 02 sensors. Those codes mean that you are running lean and that they are not matching what the MAF is saying.

Dsmfighter

+1, but I think 02 sensors are more then likey his case.

It's not hard to replace these man. 15 mins once the car is up in the air. Unplug them then slip a 6pt box end wrench over the wires down on to the sensor. Give the wrench a couple of whacks with a hammer if they are being stuborn.

timi

i think that the same codes that popped on my buddy's 04. we put it up on a lift and swapped the two 02 sensors on the left side. the rear sensor isn't bad to reach but the front one is and is way up there by the manifold (if you have manifolds) he hasn't thrown a code yet (it's been about a year).

PBiddy412

The car is stock. I am pretty sure its the front sensors and they seem very difficult to get to.

cliffyk

P1121 is a throttle position sensor DTC, P1131 has the same potential causes as P1130, here's a link to those potential problems. You can also look up P1121 on the same page...

PBiddy412

I am having problem reaching the front oxygen sensors. We jacked the car up and can see them, but can't quite reach them with our hands. Do we have to remove anything to get to them. The rear ones are easy but I'm pretty sure I have to deal with the front ones here.

cliffyk

Ford shows a special tool in the shop manual, and offset "crow's foot" sort of slotted socket...[/align][/align][/align][/align]I have seen these in specialty tool catalogs, but I don't think it a usual FLAPS thing. I changed mine when the X-pipe went on--maybe someone that's done them "in situ" can add some tips...[/align]