Error code/ check engine light after service at dealer

[Ams30]

Hi there. I bought an  sc 430 several months ago. Have not had one issue with it.  When I checked the service records there was a recommended repair of the valve  cover gasket. 

 

I got that fixed and drove it home Friday add parked the car. Today I  drive it and I  have a check engine light. I took it to advance auto to have them scan it and it is code p0440 evap emission system and p0446 evap emission system vent  control circuit. 

 

My question, could this have been screwed up or messed with or disconnected and not hooked back up after they worked on the valve  cover gasket. I also had my back brakes re done. 

 

I definitely didn't have this issue before they worked on it. 

 

Any help or opinions would be greatly appreciated. 

 

Thanks, Linda

[ShawnOklahoma]

A couple things could be happening: 

-Firstly, if it's the VSC/VSC OFF then it is very common. This is most liekly that the mechanics hooked up a OBDII reader and didn't exit the reader application properly which triggered the dash light. It is very common. There is actually a procedure to clear the light. I will post the procedure to the link. If you feel that the "jumper method" is too complicated, you can return to the shop and have them clear it and tell them you read that not exiting the ODBII app caused the light. But try the other methods below first. http://www.clublexus.com/forums/sc430-2nd-gen-2001-2010/438992-sc430-check-engine-light-vsc-and-vsc-off-light.html & http://www.clublexus.com/forums/sc430-2nd-gen-2001-2010/416764-vsc-vsc-off-lights-2.html

-The second thing that is common, is a bad gap cap seal. Try to tighten the gas cap. If this doesn't clear the light, you might have to do a ECU reset (which means disconnecting the negative side of the battery for about 5 minutes) to clear the dash light. http://www.clublexus.com/forums/sc430-2nd-gen-2001-2010/818421-check-engine-light-with-p0440-code.html

-Thirdly, loose valve covers which tend to leak oil. I've heard many owners do tighten them by hand occasionally to stop the leak. It is such a minute leak, that many do not notice it on the floor of garages or parking spots, so this could be an additional problem in your situation. Lexus charging you to replace them seems shady when a hand tightening would have solved the problem. Just saying.

-Lastly, the mechanics could have knocked off one of the EVAP lines on the drivers side near the oil dip stick (most common place for a loose EVAP line- usually from excessive engine knock indicating bad engine mounts). Check this out. If it is disconnected, reconnect it and do an ECU reset (as stated above). http://www.clublexus.com/forums/sc430-2nd-gen-2001-2010/514261-check-engine-light-on-crap.html

Oh... just found this... could be the charcoal canister of the EVAP system... http://www.clublexus.com/forums/sc430-2nd-gen-2001-2010/619081-check-engine-evap-emission-control-p0440-and-p0446.html

Good luck, Let us know what results.

[Ams30]

Thanks so much Shawn/Oklahoma. I checked all of the things you indicated and went to the dealer armed with info. So it indeed was the vacuum hoses. Being that they were original, they were hard as a rock and pretty much dry rotted, to a point. So when they disturbed the vacuum hoses to redo the valve cover gasket and then reinstalled the OLD hoses, they had lost their seal and vacuum and thus caused the check engine light to come on. 

The dealer should have seen that when it went in for the inspection or came out. I have to say that I am pretty disappointed that they mechanic didn't think twice about putting the old hoses back on. 

I got them installed, and got all of the hoses changed out, the light is now off and has been off since picking up the car today. Thank goodness. :)

[ShawnOklahoma]

You're welcome. Glad it was something simple.