Smoke Test. EGR has tiny leak. Normal ?

[cecilbridge]

2004 ford expedition running LEAN both banks. I smoke tested the truck and noticed a TINY amount of smoke coming out the bottom of the EGR valve. Is this normal ? No other smoke leaks anywhere. Codes P0171 and P0174 codes. Help please

 

[whtbronco]

There shouldn't be any smoke coming out of the bottom of the EGR valve. The diaphragm or housing has failed. Just make sure it's not coming from the gasket or the stove pipe connection.

 

[Vincent Vega]

In cases where both banks are lean, check on the vacuum hoses, especially the PCV. You might have EGR leak as you suspect, but the PCV hosing is the most common reason for lean codes for both banks on these trucks. Also the intake manifold tends to fail (mine did at 140k miles), which can cause 1 or both banks lean. I would rule out the vacuum hosing and intake manifold before replacing the EGR.

 

[Hamfisted]

Yes, you will see a small "venting" of smoke from the EGR, and the IAC valve vent holes during the smoke test. This is normal. But those are the only spots you should see any smoke escaping.