P0457

[HR radness]

I have been over a lot of threads on NABISCO and haven't found any help. I recently thre a P0457 CEL (evap leak) and I'm trying to chase it down. Along with the CEL I am getting a hesitation under boost

. So far I have checked:

all vac lines including the one that's next to the alternator with the blue fitting on it (many people who have had the same code found this had come off)

Checked the gas cap and made sure it was tight, CEL has popped up several times over the course of several fill-ups

Checked the filler neck for obvious gas smell

Looked at the charcoal canister for any loose/broken/cracked hoses

Any thoughts? smoke check the vac system?

 

[Matt]

Large or small leak?

 

[IBratmanI]

There is a small valve on the passenger side front of the intake manifold that can go bad. Mine has and I have it blocked off for now. I have a new one, but am waiting for a bigger project to replace it. But anyway, that could be the issue. I can't remember the actual name for it though.

 

[darkknight]

I'm in the process of chasing the exact same code. Says small leak. I'm running out of ideas myself.

 

[HR radness]

Do you also get a hesitation under boost?

 

[Maxxguy25RS]

How does the seal on the fuel cap and the filler neck look? I had instances where the vehicle has an evap code and the cap and seal look rusted. Also there is possibility for stuck valve on the evap canister itself. Just a few suggestions. You would be supprised at the amount of vehicles that come through my work that have evap related codes, really common.

 

[HR radness]

Cap and seal look good. How do I check the valve on the canister?

 

[darkknight]

Mine doesn't seem to have any real noticeable hesitation under boost.