* Extremely Rich Fuel Mixture: This is the most probable culprit. A very rich air/fuel mixture (too much fuel) means unburnt fuel is entering the exhaust system. Unburnt fuel ignites in the hot exhaust manifold, causing it to glow red hot. This can be caused by:
* Faulty Fuel Injectors: One or more injectors could be sticking open or delivering excessive fuel.
* Faulty Fuel Pressure Regulator: A malfunctioning regulator could be supplying too much fuel pressure.
* Mass Airflow Sensor (MAF) Problem: A faulty MAF sensor provides inaccurate air readings to the engine computer, leading to an overly rich mixture.
* Throttle Position Sensor (TPS) Issue: A faulty TPS could be misinforming the ECU about the throttle position, resulting in incorrect fuel delivery.
* Engine Control Unit (ECU) malfunction: A faulty ECU can cause various issues, including incorrect fuel mapping.
* Ignition System Problems: While less likely to cause this level of heat, a weak spark can lead to incomplete combustion, contributing to unburnt fuel in the exhaust. Check for:
* Worn Spark Plugs or Wires: Weak ignition can cause unburnt fuel.
* Faulty Ignition Coil: A failing coil can deliver weak or inconsistent sparks.
* Exhaust Restriction: Although you have a new catalytic converter, a blockage further down the exhaust system (like a crushed pipe or severely clogged muffler) can create back pressure. This back pressure can cause higher exhaust gas temperatures. While less likely to cause *red* hot, it's a factor to check.
* Turbocharger Issues: While less common, a malfunctioning turbocharger (especially a boost leak) could contribute. However, a turbo problem is less likely to result in the *entire* manifold glowing red, but could exacerbate the situation if another issue (like a rich mixture) is present.
What to do:
1. Safety First: Do NOT continue driving the car until the problem is addressed. A red-hot exhaust manifold is a serious fire hazard.
2. Diagnostics: You need a proper diagnostic scan using an OBD-II scanner to check for trouble codes. This will provide clues about potential problems with sensors, fuel delivery, or other systems.
3. Visual Inspection: Carefully inspect the entire exhaust system for any signs of blockage or damage. Look for leaks as well.
4. Fuel System Check: Check fuel pressure, and have a qualified mechanic test the fuel injectors, fuel pressure regulator, MAF sensor, and TPS.
5. Ignition System Check: Inspect spark plugs and wires for wear. Test the ignition coil.
6. Professional Help: Given the severity of the red-hot manifold, it's strongly recommended that you take your car to a qualified mechanic specializing in turbocharged vehicles. They have the tools and expertise to diagnose and repair the problem correctly.
Ignoring this issue will likely lead to significant engine damage (melted pistons, warped heads, etc.) and potentially a fire. Get it checked immediately.
