I had an engine code 3 weeks ago which had me changing the egr valve, I changed that and it was running rough and now the code is large evap leak po455.
I notice that If I take of the vacuum line that goes into the egr valve and suck on the end on the valve with the end plugged where it goes to the actual valve you can hear it suck thru the plastic area where the switch is. Is this normal?

how can I check my gas cap?
where is the evap canister?
and where is the purge/vent selonoid and how can i check that?
Thanks

 

Gas cap is hard to check unless you have a pressure tester for it. you can look at the valve in the middle and see if it looks rusty. Most years the canister is under the drivers seat. The purge solinoid is up by the air filter housing. With a large leak, you want to look at all the hoses coming off the canister and see if they are cracked. also check the harness from the purge solinoid to the throttle body and the metal line going to the canister for cracking.

 

Mine is caused by a corroded fuel filler pipe which was verified by a smoke test.

 

Start by checking all your evap hoses. One of them is either cracked or broken off. Depends on the year. But the canister and LDP pump are under the van on the driver's side.

 

I checked all the fittings/hoses/gas fill tube and all "look" good. in cluding the ones to the selonoid by the radiator. I also noticed that it runs even worse when I try to use the a/c. whats next send it to the dealer for a smoke test.
Thanks

 

Yep, but this issue has nothing to do with the running issue.

 

it doesnt? thats nnot good news....I have no other codes and this all started at the same time... again it ran fine but had a light code egr valve malfunctioned. I replaced it, light went out and it ran fine for 1 day/200 mile trip. the next morning it would buck/skip on accelaration and got a new light I plugged the vac lines to the egr just to get it home. and got the new code po455 large evap leak and thats the only code? I do notice that if you apply suction to the new egr valves switch section and plug the tube actually goes to the egr valve you can hear it suck thru the plastic part, like thru a vent. Is that normal? Thanks

 

Not sure about the suction thing, guess I've never done that. I am sure an evap leak isn't going to cause a running problem. An EGR valve will cause problems though, maybe you have a bad new valve. Wouldn't be the first time that happened.

 

I thought that to and this actually the second egr valve.

 

not a good sign, is it. Are the OE or aftermarket.