1998 Dodge Neon

Hi I have a 98 Plymouth Neon 2.0 SOHC. Manual transmission. The car has 134,000 miles. Recently the last 3 months my car began to get poor fuel economy so I changed the spark plugs and wires, air filter etc. Full tune up also had the fuel system cleaned out. The problem worsened and began stalling after driving around 15 -20 miles when id get to a stop light or a stop and go situation. Soon after the engine light came on upon taking it to a mechanic I was told my engine was running rich and since then have replaced Up & downstream o2 sensor and also MAP sensor. After replacing sensors engine light is still on and still giving rich code. I have since taking my car to the dealer and was told on these cars the ECU goes bad so upon disconnecting the ECU there was a lot of brownish liquid at the connectors. Could a failed ECU be the cause and the gradual worsening be due to this or is this liquid normal?


May 22, 2007.

The liguid is probably a dielectric grease of some kind. Hows the spark on the car, have replaced alot of coils in those for dying ang rough running. Might even be a bad injector

May 23, 2007.
My car has SAME problem, I cannot find MAP sensor. I have tried everything and then was told fuel pump heats up and then dies sometimes so that might be problem. Any idea on checking the ECU?

Aug 6, 2007.