Rep Power: 453

Well on Tuesday evening I changed out my Exhaust manifold with a new OEM one because the other one had a broken nut, but anyway everything went fine, but the next day after school the check engine light came on and that morning when driving to school, I could smell fuel in the car and on the way home. Then the next morning which was thursday, the check engine light went off. And it has stayed off since then.

Well tonight I hooked up a snap-on graphing scanner to the car and it brought up code P1456 which is EVAP Emmission control system leak detected ( Fuel Tank System ). Now my question is after the code came up, I cleared it and checked it several minutes later, then it said no codes present. Should I go ahead and check the system anyway or if the code is now cleared, just not worry about it. I was always confused about when the light just went out.

I dont smell any fuel anymore, but when the light went off, I kinda assumed the problem might have gone away, but when I read this code, I was a bit unsure. And I am not sure if my warranty will cover this. The emissions warranty ran out at 80,000 miles, but I still have abiout 17k miles left for my powertrain warranty. Someone give me some input thanks.

 
Rep Power: 296

make sure your fuel cap is on tightly...

 
Rep Power: 453

that was the first thing I checked.

 
Rep Power: 0

It could be a couple of things. First...obviously make sure your fuel cap is tight. You do still have the OE one right? Check under the hood where the vaccum hose runs to the EVAP test port.....that area. Make sure that all the lines are connected poperly. It might sound weird, but check closely on the hose's to make sure that an critter didn't crawl up in there and start eating ****. I have seen that more than a couple times. BTW...The code will most likely come back on. When you cleared the code, you reset all the rediness codes in the car. It takes a while for the car to learn everything again.

 
Rep Power: 296

There is a number of things that could be causing a pressure leak. Drop by a shop and get them to run a flow chart diagnostic.

 
Rep Power: 453

Now why would I do that. I am going to school to be a technician, I can do this at home.

Anyway, I was just curious about all this because the light came on the day after my new OEM header install, then went away the next morning while sitting at school. And hasnt come back since. I scanned the ECU about 4 days after the light went off and it gave me the p1456 code and I cleared it, but should I still run the test to see if there is a problem, or would it be ok if the light went off? The car still runs fine, but just curious.

 
Rep Power: 296

well, I keep having an intermiten problem (i havn't scanned it) but it causes the tranny not to shift properly, and not go into vtec.. its really messed up. But it goes away after a couple starts and works fine right after. I'm thinking its just a bad connection to the speed sensor but I dont have a scanner. Neway, it fixes it self so Im not going to put the money into fixing it.

If it comes back, I think you should look into it, otherwise if everything is running fine then leave it be.