Originally Posted by clemson61
Replaced the egr block near the exhaust manifold. Didnt fix the check engine light
Not sure what the "EGR block" is???
EGR system has 3 parts
1. EGR Valve, vacuum hose is used to open valve and allow exhaust gases to enter intake when engine is under load
2. EGR modulator, computer controlled valve, it has electrical connector and 2 vacuum hoses, 1 to EGR valve and 1 to intake manifold, computer uses this valve to increase vacuum at EGR valve to open it.
3. DPFE sensor, it has electrical connector and 2 hoses to exhaust manifold, 1 hose is near, or on, the EGR valve tube, the other hose is on the exhaust manifold, this sensor detects pressure changes, if EGR valve opens the pressure in the hose near the EGR Valve will drop more than the pressure in the hose farther away, this pressure "differential" tells the computer how much exhaust gas is entering the intake thru the open EGR Valve, the "flow".
DPFE = differential pressure feedback
The two hose are marked and must not be reversed.