EGR Flow

[732Galant]

Threw a code for EGR Flow malfunction. Guy who read it at Advanced Auto Parts said it probably just needs to be cleaned. He's not a mechanic though so I come to you, the people of TGC, in hopes of a resolution. Thanks in advance.

[WarmAndSCSI]

Was it a P0401 (insufficient flow) or a P0402 (excessive flow)? Insufficient flow could mean either a partially blocked EGR tube, blocked EGR pathway in the intake, sticking EGR valve (stuck closed), or a malfunctioning EGR solenoid. Excessive flow could mean that your EGR valve is stuck open and needs to be cleaned. Might also mean the solenoid is stuck open. It's best to check everything.

Start with inspecting and cleaning the EGR valve. I'll post a picture of the EGR valve if you don't know what it is.

Please specify whether you have a 6G72 or a 4G64 so we can help you with the specifics.

[732Galant]

I have a 4G64. This was a while ago I got it scanned and I just wanted to see if anyone knew because inspection is next month. It was EGR Flow Malfunction, not to sure if this is right but %90 (I lost the print out) but I think the code was P0400. I have a spare EGR valve from when I had the intake manifold replaced. Should I just clean that one up (used manifold) and throw that one on or clean this one and see if it works? Also would SeaFoam clear it out without having to take it off? Thanks again.

[WarmAndSCSI]

Swapping it out will be the best option. Usually you let SeaFoam get sucked into the intake manifold, but it won't go through the EGR since the EGR sucks its air from the exhaust. The SeaFoam has lost its cleaning abilities once it's been burnt in the combustion chamber.

[732Galant]

ok, I guess I will clean up the other EGR valve I have. Soak in throttle body cleaner or PB Blaster or something then throw it on. Thanks for the advice.