Hey Chevy Lovers,
here's a tuff one; My 98 venture van has had these codes for about two months and it time to do my emissions. I check the wires from the fuel pump and found out they were badly corroded, so I replace the wires. before replacing the wires my guage did not work. after, my guage (fuel) works fine but the codes are still present can anyone help?
Also Where is the fuel pressure sensor located?

Pressure sensor is on top of the tank, don't see 1639 though.

Now that you have fixed the problem, remove the cables from your battery to clear the codes, or go to autozone, and they can clear it if it still does it.

My local AutoZone (North Canton, OH) said they are not allowed to clear codes.

Might just be a local thing.

You know whats funny, you can buy the exact scanner that autozone uses from autozone and can clear it, I dont see the big deal. If you vehicle is throwing codes, it will throw it again when you start your van at the emissions station. Thats why they tell you to turn it off...

The problem is when the codes are cleared using an actron scanner
that Autozone or Advance Auto parts sales it shuts down all computer cycling functions for at least 4 cycles. Which basically means to you is that none of your secondary systems such as antilock brakes and air bags will work for those cycles. Which means to those companies if you get into an accident when you leave and these devices fail to work they are now held responsible
this is the reason either company will no longer erase your codes. Besides if you fix the problem your computer will erase your codes after four cycles for you. Or you can take it to a shop where they have the proper equipment to erase codes with and pay the $60-$70 and have it done.

The problem is when the codes are cleared using an actron scanner
that Autozone or Advance Auto parts sales it shuts down all computer cycling functions for at least 4 cycles. Which basically means to you is that none of your secondary systems such as antilock brakes and air bags will work for those cycles. Which means to those companies if you get into an accident when you leave and these devices fail to work they are now held responsible
this is the reason either company will no longer erase your codes. Besides if you fix the problem your computer will erase your codes after four cycles for you. Or you can take it to a shop where they have the proper equipment to erase codes with and pay the $60-$70 and have it done.

This doesn't make sense though. If you take your car in for a repair they will shut off the light (often just so the light is not on after they make the repair and for the benefit of those who do not understand the drive cycle etc. and that the code will clear itself) Would this not mean that they are then liable for an accident where the air bag of ABS systems fail to operate.

If the ABS system was disabled for 4 drive cycles after a code reset then wouldn't the ABS warning light illuminate? (If not then I can see GM being partially liable too)

There are several posted warnings about the learned parameters being reset with a code clear but never is it mentioned that the ABS and Airbags will be temporarilly disabled. I would expect a warning in the owner's manual when talking about disconnecting the battery or in my Haynes manual. The Haynes specifically mentions disabling the airbags when working near them specifically for liability issues.

If the Autozone will not clear the codes it is most likely due to the fact that there is a belief somewhere that emissions tests can be jeopordized. I don't know why testing centres even care about the light. In Ontario they used to ensure that it came on when the car was started (to ensure the bulb is there) and the codes could not have been recently cleared (all of the built in monitors had to be in the ready state) and the light can not be constantly on. They changed that rule now such that they don't care what the light is doing as long as the emissions are clean.

I have NEVER heard of safety systems being disabled for 4 drive cycles just because you cleared the codes. That would be financial suicide for a car company because of the liability involved. I suspect that the store just didn't want to hassle with clearing codes for people.