2001 CHEVY SILVERADO DTC CODE QESTION

[1977 chevy trucks]

The engine light on my 01 Silverado came on recently,so I ran a code scan and came up with code 0440,which apparently is an emission control system fault,but thats pretty vague,so I was wondering if anyone out there has any ideas about which parts Imight have to replace? The truck is a 4x4 with the 5.3,automatic,and about 160000 miles.Also,same truck has a heck of a rattle when started cold,it goes away in about 5 minutes and it usually only happens when first started for the day.It also makes an unusual amount of exhaust vapor and really runs like crap when cold.Ive heard some of these engines hadpiston slap when cold so the rattle is nothing to worry about.I dont realy believe that...Do these engines have a pressed on harmonic balancer that can come loose?Maybe thats the rattle.Any help would be greatly appreciated,Hugh.

 

[hurst01]

77 chevy trucks,

Check the fuel cap to makes sure it is not leaking. The code 0440 is for Evaporative emissions leak. There is several things that can cause the leak in the system but I would check the fuel cap first. If this doesn't help you will have to do further diagnostics.

Good luck,