Help - I get really lousy mileage - 8.2 MPG!

[Moshe]

I looked on the exhaust, and I saw a little hole that is closed up with a nut. Is that where the o2 sensor is supposed to go? See attached pictures.

When I called yet another mechanic, to price the o2 sensor (this one is an official UMI [united motors international] mechanic), he too told me that there are models without o2 sensors, and he has to see the car. Is there any reason that GM would build some models without the sensor? No "check engine now" light is lit by me - and I'd guess that one should be lit if the o2 sensor is missing.

[Astro-van.de]

Hi,

is the "SES"-Light on, when you turn on the Ignition ? (or is there no Bulb in there)

regards Jens

[Moshe]

When I put the key in and turn it, the light goes on for a few seconds and then turns off. To the best of my knowledge, it works.

[kidhauler]

Yes the bolt in your exhaust is where the O2 sensor should bolt in. It would also plug into the 3 wire plug that you found hanging beside the transmission. Since you have had such a tough time finding a mechanic that knows anything about North Americain cars make sure that you get a 3wire heated sensor. If they order the wrong one you will not be able to hook it up.
Once you have the sensor plugged it your mileage will get much much better. Make sure that when you put in the sensor in you leave the grey goopy stuff on the threads. It is called never seize and will stop the sensor from becoming stuck in the exhaust pipe.

[Moshe]

Kidhauler: Thanks.

I think I'll just order an o2 sensor in the USA and have it sent to me. I'll then find a local mechanic who is willing to follow directions and simply install the darn thing.

Which brand would you recommend? I see that there are lots of brands, ranging from $25 - $100 or so.

Thanks

Moshe

[kidhauler]

I have used the NGK sensors in my van and have been fairly happy with them. If I were you I would think about ordering 2-3 since you have to have them shipped so far and it is a part that will go bad every so often. If your only going to order one then get the best one on the market. (most expensive is my guess) I usually get the NGK because they have a one year warrenty on them so I keep my receipt and exchange them often. However you do not have the option of returning the part. You can usually intall the sensor unit with a cresent wrench in about 5 minutes. I have even swapped a sensor on the side of the highway when I was trying to diagnose a problem.

You might have a hard time getting that bolt out of the exhaust take it for a drive and get the exhaust nice and hot to try and loosen up the bolt. If you can't get it you can just drill another hole slightly ahead of the one that is there and then weld on a nut with the right size threads and use that to mount the sensor.

Good luck it sounds like your on the right track at long last.

Kevin

[dcarlson12]

That connector is obviously very dirty so you are definitely going to need to put some effort into cleaning it well before plugging the sensor connector into it.....
Keep us informed how it goes....
Good luck.

[Moshe]

OK- I ordered a Denso o2 Sensor - it was delivered in the US yesterday - hopefully I'll have it quickly.

How do you recommend cleaning the the connector? Soap and water when the engine is off and no current is running through it or do I need to disconnect the battery as well?

[kidhauler]

I would use some wd-40 and a little bit of scrubbing with a small metal brush. Just scrub lightly when the engine is off. You could give it a shot of engine degreaser on the outside of the plug to remove the really gross stuff. I would also give it a shot of white lithium grease on the conectors before you plug it in.

Hope you get the van fixed up soon.

[Moshe]

Thanks to everyone for their help! The O2 sensor is finally in the car - it cost me $10 at a local mechanic to have him install it - I would never have been able to get the bolt out of the hole - he needed to use an air powered thingee to get it out. Took about 15 minutes.

I'll post my mileage when I figure out the new mileage - it will be a few weeks before go through two tanks of gas.

Thanks again for all of your help!

[dcarlson12]

Never heard back from you. What were your results?

[timelessbeing]

So how do you check if the fuel injectors are working properly anyways?