I replaced 3 of the 4 O2 sensors and tried working on the front bank, upstream sensor today. It is so tight in there, that I could barely get the socket up in there with a wrench on it. I had to resort to an adjustable socket wrench with the head turned to a pretty sharp angle which was putting alot of incorrect stress on the sensor when I turned it. It didn't budge, and I was worried that putting anymore torque on it would bust it off. I tried working from underneath the vehicle and also down through the top, but nothing worked.
Any suggestions on getting this thing out?
I have the socket and can get it onto the sensor along with a wrench, but theres not enough room to turn the wrench. I tried one of the wrench's that have an adjustable-angle head, but it has to be at such a severe angle that its putting torque on the sensor that isn't correct. I felt like I was about to bust the sensor.
The reason I'm changing all four of them is because I had one that went bad and when I talked to my mechanic, he suggested I do the rest. He said they get pretty dirty and if one has gone bad the others may not be far behind. He also mentioned they should be replaced because your gas mileage and efficiency suffers. The ones that I did get out were pretty black.
I've heard both theories on that, the one you received which bears merit, and the old "if it ain't broke, don't fix it" which is not always right, but can also have merit. I've had 2 Grand Prix's and have had to replace one sensor on each, of course it was the one by the firewall (the other 2 are a breeze to get to). You might have to electrically disconnect it and drop the manifold so that you can get on it. That might not be easy, either, under the assumption that you have at least 80000 miles on the car, exhaust bolts don't break away very easily.
Best penetrant that I've ever used is Kroil by Kano. If you can find it, soak it well several times, then try it. Heat also may help if you have acetylene, but if you've all ready used a penetrant, degrease it first. Not sure exactly where it's located, but if you remove the radiator, can you get a better hold on it?
Yeah, I was thinking that the only way to get a good angle on it would be to remove the grill and radiator, which would be a huge PITA.
All of the sudden the check engine light came on again yesterday and the code is showing the rear bank, upstream sensor which is only a few weeks old...
I don't know why that would be throwing a code all of a sudden.
I think the radiator can be removed without touching the grill. It would be a lot safer, at least mentally, to have the radiator target removed from the range of all the wrenching. I have punched a hole accidentally while trying to loosen a rusty fastener, and it was not pretty. Cost a bit to get fixed, so if there is any chance, I'll take the time. Doing timing belt on a Ranger 2.3, it was nice to have the radiator out, lots more room.
Re the O2 sensor message, I'd be checking that the wires are connected tightly and haven't disconnected or landed on a hot exhaust pipe and melted. It's unlikely you could have failed sensors that quickly.
I'm wondering if it isn't the electrical connection. I noticed when I connected them the first time, that I didn't get a "click" as I would if they locked together. Also today, when I disconnected it again, I didn't have to touch the locking tab on the female end to get it apart. There seems to be a little play in the connection, and if I pull on it enough, it slips right out.
I'm wondering if theres a defect in the new part or maybe that locking tab broke off when I took out the old one.
I just took a look at it and the tab must have broken off of the female connection from the computer. There is a place on the male end of the sensor wire where the tab should lock in, but its missing on the other connector. I was able to get a pair of pliers down in there and get it tightly connected, but I'll have to drive it a little to see if that helped.
After some more research, I found that I made a mistake on which sensor I thought I was having issues with. The code I'm getting now is a heater circuit malfunction for the front, (closest to the grille), upstream sensor. This is the only one out of four that I didn't change out because it was such a PITA to get to and I can't get a wrench up there to get it out. I may have damaged the wiring while trying to do so. I have a new sensor on hand, but no way to remove the old one without removing the radiator. I'm going to look to see if Craftsman makes a "stubby" 3/8" socket wrench, and maybe I can get that on there and have enough room to turn it.
The AutoGuide.com network consists of the largest network of enthusiast-owned enthusiast-operated automotive communities.
AutoGuide.com provides the latest car reviews, auto show coverage, new car prices, and automotive news. The AutoGuide network operates more than 100 automotive forums where our users consult peers for shopping information and advice, and share opinions as a community.