Regulator location on 4-cylinder engines
1. Regulator
2. Vacuum hose
3. Return hose
1. Disconnect and plug the fuel pressure regulator vacuum hose. Connect a hand vacuum pump to the regulator. Start the engine and read the fuel pressure without regulator vacuum. Create a negative pressure in the regulator and read the fuel pressure again. As the vacuum at the regulator increases, the fuel pressure should decrease. Compare pressure with normative.
2. Connect the vacuum hose to the regulator and check the fuel pressure at idle. Compare pressure with normative. Disconnect the hose and read the pressure again - as soon as the hose is disconnected, the pressure should rise abruptly to the upper limit. If the fuel pressure at idle with the hose disconnected is too high, measure the vacuum on the vacuum hose with a vacuum gauge. If the vacuum gauge shows nothing, then check the tightness of the hose, suction manifold and surge chamber.
3. If the fuel pressure is low, securely clamp the fuel return line and read the fuel pressure readings. If the pressure does not increase, then the fuel pump is faulty, or the fuel supply line is clogged. If the pressure rises sharply, replace the pressure regulator.
4. If the fuel pressure is too high, decompress the system, disconnect the fuel return line and purge. If the fuel line is not clogged, then the pressure regulator.
5. If the pressure behavior differs from that described in point 2, replace the pressure regulator.
6. Decompress and remove the pressure gauge.
7. Wrap the fitting of the fuel distributor after replacing the gaskets.
8. Wipe up spilled gasoline. Start the engine and check for fuel leaks.