Parts for your 1999 Mitsubishi Lancer-Egr valve

1999 Mitsubishi Lancer EGR Valve — What It Does and How to Look After It

Technical sources indicate the 1999 Mitsubishi Lancer (CE series) is fitted with an EGR valve on its petrol variants sold in Australia and New Zealand, notably the 1.8L 4G93. This is documented in the Mitsubishi CE Lancer Workshop Manual under Emission Control (EGR System), the Gregory’s Mirage/Lancer 1996–2001 manual, and the Mitsubishi ASA parts catalogue, which lists EGR valve and gasket part numbers for 1999 AU/NZ models.

The EGR (Exhaust Gas Recirculation) valve recirculates a measured amount of exhaust back into the intake. That lowers combustion temperatures, which cuts NOx emissions, helps prevent pinging under light load, and can slightly smooth cruise efficiency. On a ’99 Lancer, it’s ECU-controlled via a vacuum or stepper arrangement, opening mainly at warm, part‑throttle cruise.

For servicing, it’s not a regular replacement item, but it does like a clean now and then. Carbon can build up and make the pintle stick open or shut, causing a rough idle, hesitation off the lights, higher fuel use, or a check engine light (often EGR flow codes). A good rule of thumb is to inspect the valve, gasket seal, vacuum hoses and the EGR passageways every 40,000–60,000 km, or whenever doing a major tune.

Cleaning is straightforward if tackled carefully. Remove the valve when the engine is cool, cap the ports, and use a suitable EGR/throttle-body cleaner and a soft brush to clear carbon from the pintle and the passages in the manifold. Avoid gouging the seat. Always fit a new gasket on refit, torque to spec from the manual, and check any control solenoid and hoses for cracks or leaks. On the 4G93, access is usually at the rear of the cylinder head near the firewall, allow extra time if working with basic tools.

If the valve is electrically faulty, the diaphragm is torn, or the shaft is badly worn, replacement is smarter than repeated cleans. Quality OEM or reputable aftermarket parts are fine, just make sure the part number matches your engine and ADR-spec. After refitting, clear codes, and let the ECU relearn idle. Good quality fuel, a healthy PCV system, and the odd decent highway run will help keep the EGR and intake from coking up again.

• Typical signs of trouble: rough idle, stalling when hot, pinging on hills, higher fuel use, or a stored EGR flow code.
• Handy service tip: replace brittle vacuum hoses and the EGR gasket any time the valve comes off.

Popular questions

Where is the EGR valve on a 1999 Mitsubishi Lancer?

On most AU/NZ 1.8L 4G93 cars it’s mounted at the back of the cylinder head, near the firewall, with a metal pipe running to the intake. It can be a bit tight for access, so a small ratchet and patience go a long way.

Can they drive with a faulty EGR valve?

It will usually run, but it may idle poorly, use more fuel, and risk engine pinging or emissions test failure. Driving for long with a stuck-open valve can foul plugs and make it stall at idle, so it’s best to fix sooner rather than later.

Is cleaning or replacing better on the CE Lancer?

If the valve is just carboned up, a careful clean and new gasket often restores normal operation. If the diaphragm is split, the pintle is loose, or there are electrical faults, replacement is the reliable fix.