I just had my intake gaskets replaced and my truck runs like it was new. My question is the tech told me there was a code P0456 (he beleived) that would probably come back. I have driven it quite a few miles(200) since then and still no code. He said it was an emmissions code and it would run fine. What is this code and can I expect it to come back? I was under the impression that the emmissions system was seperate, but could it have been the lean condition that the engine was under with the bad gaskets? Thanks!

After some research, I believe the code to be either a P0446 or a P0455 which are both evap codes. I called the tech again and he "doesnt remember.":banghead: The good news is that it hasnt come back yet! I will post back if it does.

Sounds shady to me. If I read it right.....If you had a check engine light, and he was supposed to fix the problem, the light would/should NOT come back. IF the problem was actually fixed. If he "don't remember" then he is probably trying to cover his butt since your now researching the problem. Sounds like you should find another tech to me.

Sorry, he was fixing a P0300 code. The truck ran like crap because the intake gaskets were shot. There has been an emissions code in there for ages and since the gaskets were replaced, it has not come back. He offered to look at it again at no charge if it came back for the evap system. But that was not my original concern. I was just wondering if anyone has heard of this before?

I just had my intake gaskets replaced and my truck runs like it was new. My question is the tech told me there was a code P0456 (he beleived) that would probably come back. I have driven it quite a few miles(200) since then and still no code. He said it was an emmissions code and it would run fine. What is this code and can I expect it to come back? I was under the impression that the emmissions system was seperate, but could it have been the lean condition that the engine was under with the bad gaskets? Thanks!

are you sure it's p0456 ? not p0446....

Yes, it could have been a 0446 or a 0455... The number he gave me was a 0456 and he said he couldnt remember exactly. Like I said, it wasnt the problem he was supposed to be fixing.

are you sure it's p0456 ? not p0446....

if this is the p0446 code you will find an excellant discription in these forums describing this fix.....it is basicly the pressure/vacuum in the gas tank is not acceptable to pcm/computer .....gas cap/ purge valve,plugged purge valve, purge lines rusted/damaged etc.....driving off road dust at vapor cannister area where vent is located gets plugged up...also pictures were posted for locations of componets....

All I was curious about is why it would go away with new intake gaskets? I am not fixing it if it isnt broken. When and if the code comes back I will address it. Thanks

All I was curious about is why it would go away with new intake gaskets? I am not fixing it if it isnt broken. When and if the code comes back I will address it. Thanks

some of this tubing that is part of the purge system is above intake this only needs a small leak to throw code perhaps the reinstallation corrected this leak....