I have a 99 z71 silv. w/a 5.3L automatic. I have been popping code P0442 on this thing for a while and it is starting to anoy me.

Can anyone give me an idea as to where to look to fix this problem??

(P0422 = EVAP Emm. Control Sys Leak {small})
Also, it has 131,000 + miles on it.

THANX

 

Easiest thing to check is the gas cap/ gas cap gasket. If the gas cap isn't sealing, you will get an EVAP code for a small leak.

 

That was first thing I did...In fact, I went and purchased a new Locking cap since I live on the Gulf Coast anyway. (still don't trust the out of towners)

 

Cap would've been my first thought (b/c it's easiest to check). Check out this link to get a general idea as to what's going on with the EVAP system, and what to troubleshoot:

http://www.tankota.net/repair/Repair...3/cip0442p.pdf

 

I have that same code keep comming up in my truck as well. I am not sure of what the problem is either.

The link above dosent work....

 

I went to Advance Auto Parts and purchased the Actron OBD II so I could clear those little anoyances, but when it started to occur weekly, I thought I would check with everyone and see what they think.

 

I dunno if this will help you out or not, but worth a shot..

http://gearchatter.com/viewtopic9351...5b9660e6a9ae1c

 

The charcoal cannister is right on the driver's side next to the frame rail, behind the gas tank. Take a peek and see if any hoses got disconnected or maybe a rock jumped up and cracked the cannister.

 

Swap back to stock gas cap clear codes and retest. seemn this alot with locking caps. Did your prob start after the new cap? Keep us posted.

 

How much would a new cannister cost??....a buddy of mine that used to be a mechanic before joining the military suggested replacing that due to the mileage on the vehicle.