Infrequent Check Engine Light - Red

I have a 1994 Plymouth Grand Voyager with 120K miles. It runs very well. But recently I have been getting a Red Check Engine Light. If I oull over and restart the minivan, it goes away. I have also noticed that it comes after I drive 10-15 miles at steady highway speed. Please help.

How well has this vehicle been maintained?

The first step when a CEL is lit up is to have the stored trouble codes read. If I recall correctly, this vehicle uses the old OBD I diagnostic system which will not give codes as specific as the later OBD II systems. However, it should still help to point a mechanic in the right direction to resolve the problem(s).

Anyway, this situation does suggest poor maintenance. I would suggest that you start with basic maintenance, such as replacing spark plugs and air filter.

I do not presume any poor maintenance. Almost seems insulting reading it but I know not your intention. Nevertheless I would not be tempted to “maintain” a 15 year old vehicle beyond oil changes and acute problems especially with a value of around $1000 or less.

It could be anything with the vehicle including bad O2 sensor or intermittent reading from a sensor. The vehicle is 15 years old which an achievement in itself.

It may be hard to diagnose however if it clicks on drive it straight to mechanic leaving the engine running and get the code read.

Here’s the instructions on how to pull the OBDI Diagnostic Trouble Codes from the computer, and the code definitions.