1997 Ford Escort, has 130,000 km on it. Equipped with manual transmission. Please help me diagnose what is wrong with it.
Here are the symptoms:1."Service engine soon" light camp up last night. 2. Intermittently, idel speed is unstable; it fluctuates quickly between 500-100 rpm. It feels like stalling. This happened 1 week before the service enging light showed up. 3. When (2) happens, the exhaust fume has pungent smell. 4. When (2) happens, engine pullback is stronger when lifting the gas before chaning the gear. Clearly feel it in 2nd and 3rd gears. 5. High pitch noise from the dashboard (like whistle), noticeable when turn off the engine. This noise has been going on for 6 months with no other symptoms.
Here are the symptoms: