Jul 08 2008
Since last week the Check Engine light has stayed on
Question:
I have a 1999 Ford Ranger with 105,000 miles on it. It runs really well. Since last week the Check Engine light has stayed on. I have checked all the fluids which all appear fine except for the Radiator coolant. In the coolant reservoir the coolant is very low and a brownish transparent color. In the radiator? at the front of the truck the fluid is transparent green (sort of neon) and full. Are they supposed to be different and would this cause my Check Engine light to stay on?
Answer:
The check engine soon light comes on when the on-board computer detects a fault in either engine drive-ability or performance, transmission control or transmission, or emissions control system. There are literally hundreds of reasons that the check engine light can be set- ranging from a vacuum hose leak, engine misfire, loss of engine compression, on of dozens of engine sensors, transmission solenoid or control module, internal transmission failure, emissions leak, or main computer malfunction.
The only way to find out what the problem is, is to have a diagnostic scanner hooked up to the computer and read for stored trouble codes. You can either take it into a shop and pay for this test. They will perform the diagnostic scan, and then do the necessary diagnostic troubleshooting to isolate problem. Or, you can take it by an Autozone, or most other parts stores, and they will do the diagnostic scan for FREE. they will tell you what the trouble code number is and what it generally refers to. BUT, they cannot do the diagnostic troubleshooting necessary to determine what part, if any, has failed, or whether it is an open/short in wiring, or other cause of problem.
If you choose to have Autozone do the scan, you can re-open this question and post the trouble code number here(the post will come directly to me), and i will give you the steps for troubleshooting and repairing the problem, or advise that this is something that can only be dealt with at a repair shop. i will do this for no additional charge(once original Accept is made) and continue to help until problem resolved.
Because there are so many possibilities of what is setting the light, it would be irresponsible of me to speculate as to the cause. Any guess on my part at this point would be a waste of your money and time on replacing parts that are most likely OK.
As far as the coolant color, although it is possible that it is related to the check engine light, it is most likely that the coolant in the overflow tank has some rust or sediment in it causing the color difference, a lot of times the sediment or rust in a cooling system will settle in the overflow tank over time.. To make sure though, you can have a coolant pressure test done to make sure that there are no internal leaks such as leaking head gasket or intake manifold gasket. Also have the coolant properties tested to make sure that it has broken down over time(it may just be time for a good coolant flush).
