Service Engine Light on 2002 Venture

[baby141]

Please help. My 2002 Chevy Venture on has been breaking down for the last 4 months. This month the service engine light came on. Took it in for servicing and they did a code scan to see what is wrong. The diagnose analysis was as follows:
PO341 - Lamp sensor circuit out of range
PO462 - Fuel level sensor circuit signal high/pen
P1189 - Engine oil pressure switch circuit

And then, the mechanic cleared the codes. Once he cleared the codes he said some issues were ruled out (whatever that means) and the only three possible causes if the light comes back on is:
1. faulty sensor
2. wiring problem
3. ECM (computer)

This is what I don't get. He cleared the codes without fixing any problems. Now I'm waiting for the light to come back on so he can then look at the three items above. Does this sound right? Could he have "fixed" the problem by clearing the codes and could there be a chance the service engine light will not appear again?
I'm so confused. This is our only vehicle and finances are really low right now. I'm so worried...

[Tech II]

Was this a GM shop?

P0341 has to do with the cam sensor....does the vehicle intermittantly run rough/stumble?

P0462 means means your gas gage is probably erratic....

P1189, is usually an oil pressure sensor problem....

[baby141]

I have not experienced the vehicle stumbling. It runs smooth... so far.

I do have an erratic fuel gauge but it has been like that the last two years. The service light is just popping up now. Could that be why the service light is on?

I do have a slight oil leak coming from the front, passenger side. Could that be related to the P1189 code?

He also mentioned the two front wheels. need new bearings. Is this why the light is on. Sorry for all the dumb questions but I don't have any knowledge in car repairs.

I took it to a Canadian Tire mechanic. It was not a GM shop. Does it sounds right that he said he "cleared the codes" so the other three issues are ruled out? Basically, I'm to drive the vehicle until the light comes on again. Very unnerving. I cart two small children around and I don't want to be stranded some where.

Also, the light came back on 6 days after he "cleared" them. What can be wrong based on the diagnosis above. please help! I don't have money for major repairs or a new van.

[SilverOLDS]

I would suggest another shop. My experience with CT has not been good. Maybe Master Mechanic or ask friends where they go. Referals can help.