I need help, I've been only getting about 240-250 miles on a tank full of gas. I know 300 miles is possible on a full tank. Anyways went to auto zone and checked the CEL, code=p1457 came up with the reader saying "unable to pull vacuum". I've done a tune up and changed both O2 sensors. Anyone have any idea what this is and how it can be fixed?

Thanks in advance.

 

P1457 = Evaporative Emissions (EVAP) Control System Leakage (EVAP Canister System)

 

Evap? Hmm is there a DIY to fix this problem or would I have a better chance taking it to Honda? Btw, how much would it cost to fix this CEL?

 

theres a black canister that is bolted onto your firewall underneath the battery, check to make sure all the hoses are connected securely.

 

What year is your car? Canister side EVAP leaks could be a few different things, like the canister vent shut valve(I just did one today!), canister purge solenoid, etc. If you've never had to do troubleshooting on those systems before it may be better to take it in. For the cost of a diagnosis they can do the scan and function tests and tell you exactly what you need, and you could even replace it yourself. Most of those components are really easy to replace, but you have to know which ones to do, and to know that you need to do the right tests.

I know this is going to get under some people's skin, but Autozone scans yield some pretty weird results. They have strange interpretations of a lot of manufacturer controlled DTCs, like the one they gave you for an EVAP code. You are best off making friends with someone who atleast has a Snap On scanner or PGM Tester, if not a HDS (Honda Diagnostic System).

Anyways, Fuel Delivery section in the Helms I believe, and you will need a multi meter and vacuum pump. Canister Side leaks could be the shut valve, any of the solenoids, or the canister itself.

 

The car is a 2000 Si, bought it for $4700 w/ body damage. Anyways CEL light was on when I bought and at the time I check it, it was the O2 sensors. After a few days it came on again.

 

Hrm, possibly the charcoal canister is cracked...

Do Hondas even have charcoal canisters??