My car is 1998 V70 awd. Check engine light is on. OBDII Codes P0455 and P0440.

Need any suggestion. What's the first things to do?

With thanks.

gairy

More than likely it is your EVAP valve malfunctioning. Locate the valve on the radiator support sort of underneath the cold air intake. I should have two hoses and a Bosch type electrical connector attached. Trace the hose to the intake manifold and make sure it is not cracked, dry rotted, leaking etc. then remove the valve and using a vacuum pump, check each side to see if it will hold a vacuum. If not, replace. You can also apply 12volts to the spade terminals and listen for a click of the solenoid.

Might want to check: the EVAP emmission control system has a large leak.
Possibly a vacuum leak.

Klaus
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1975 164E running? 1995 854T sweet 1998 V70 R work horse

Like others have said, evap leak, but sometimes it's not a major component but a matter of tightening your gas cap. Tighten it several clicks, reset your code and see if it comes back. If it does, then look for the other issues.
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1998 S70 T5 Emarald Green Metallic (125K), 2004 V70 2.5T Ruby Red (45K), Previous Owner of Black '94 850 Turbo Wagon (Sold at 140K and miss her). My cars have been running so well lately they've got me worried.

My check engine is throwing the same codes and I've been sold (2) new gas caps. Thanks for the additional information, which I will use this when asking my mechanic to investigate beyond new gas caps.

One note, my a/c has been faulty and when I have it worked on and recharged, the check engine light will go off about 6hrs running time. Eventually, it comes back on but my mechanic swears that the a/c system isn't linked to the computer dianogstic.

jg

I had a check engine light that would sometimes not come on for a few weeks, and sometimes during a long drive. The dealer said to check the gas cap, and after several visits to test and reset the light, I bought a replacement cap. That didn't fix it. This went on for about a year or so until a dealer tech checked a little deeper and found that two hoses leading to an evap canister had been swapped when it was replaced. He corrected that and it hasn't recurred (been almost two years).