Hi gang, I just failed inspection for emissions and safety issues. The emissions is a 1491 code which I am wondering should I change the evap purge solonoid or the evap ldp. The truck is a 2002 1500 4.7. I failed for the same code 2 yrs ago and I changed the gas cap and that worked, but not this time. I would like to know what is the probable cause for this code and is there anything elese I should look into in case that is not the problem. The other issue is a variance in the side to side movement of my front suspension. The inspection center said to consider damper replacement. What the hell is a damper. If I got a front wheel alignment would that correct the problem? I have the Haynes manual and there is not any mention of a damper on the front suspesion, unless they are talking about the stabilizing bar. I would appreciate any and all help. Thanks

 

sounds like they are talking about the stabilizer

 

Move out of the gay states that make you get inspected

 

I agree. This state bleeds you dry every chance they get, but since I'm here I need to get this damn thing fixed or they'll take more money out of my pocket. Any suggs?. Thanks

 

This may be a little late but I just had the same problem and that's how I found this post. I drove through a fairly large puddle the other day and my check engine light has been on since. I've pulled the code with my scan tool about 5 times and erased it each time, just to have it come on as soon as I start the truck. My scan tool was giving me a 1491 code also and it said "Manufacture Controlled Emmission Control". I had no Idea where to start so I got on this forum and searched "1491 code". I found more than a dozen threads about the 1491 code but they all said it was a fan relay fault. Go figure, I went out to my truck and the fuse for my A/C fan was blown. Replaced it and no more light. You might want to take a look at that before you spend too much on chasing the wrong problem.
As for the side to side play, having a 2002 1500 you should have an indipendent front suspension which usally doesn't give much play even when it's worn. I would give your wheel bearings a shake with the truck off the ground and see if they might have some excessive play, my 2002 only has 60k on it and I've already had to replace both of them.
Well, hope this helps. If not keep looking, this place is full of great people who really know what they are talking about.

 

This is kind of related to this discussion. Most modern engines with catalytic converters produce almost all of their green house gas contributing pollution in the first 15-20 minutes of operation until the cat gets up to operating temp. So to stack the odds in you favor when going for emissions testing drive around for half an hour and then leave it running while you're waiting for them to let you bring it in. That trick cut the emissions on my dads 96 buick in half since the time before I told him.