Honda Acura NSX 1991 Service Manual page 304

Emission Control System
-Exhaust Gas Recirculation System
Troubleshooting Flowchart
, culation
, I
The EGR System is designed to reduce oxides of nitrogen emissions (NOx)
take manifold into the combustion chambers. It is composed of the EGR valve, CVC valve, EGR control solenoid valve, PGM-FI ECU and
various sensors.
The ECU contains memories for ideal EGR valve lifts for varying operating conditions. The EGR valve lift sensor detects the amount of EGR
valve lift and sends the information to the ECU. The ECU then compares it with the ideal EGR valve lift which is determined by signals
sent from the other sensors. If there is any difference between the two, the ECU cuts current to the EGR control solenoid valve to reduce
vacuum applied to the EGR valve.
E G R
VALVE
LIFT
SENSOR
11-128
12: Most likely a problem in the Exhaust
by recirculating exhaust gas through the EGR valve and the in-
- -