Check engine light is now on?

SUV is making an awful noise out the rear end sounds like its coming from muffler. Service engine light is flashing. When idling it doesn't do any of this. Please help. Have never had an issue with my vehicle.

Check engine light on

https://www.2carpros.com/articles/service-engine-soon-or-check-engine-light-on-or-flashing

Have the computer scanned for code/s-you have a problem within the engine management system that caused the CEL to turn on-This is your starting point of diagnosis,finding out what's going on.

I reciently had a cylinder mis-firing that appeared to only be a loose connection. That problem triggered a check engine light. I have been monitoring the code checker to see if the misfire reappeares and have noticed that I have 2 monitoring tests that have not run if I read the information properly as they keep flashing on the monitor.

I also have a yellow light indicating the non running of these monitors. I have cycled the car through several trips and after saving the data off the computer, I reset the computer. It has not illumintated the check engine lamp and there are no diagnostic toruble codes stored in the computer.

The tests are the catalist monitor and the EVAP system monitor. I just had the smog checked last week and it passed in all catigories.

Am I too worried about these test not performing or should I be looking for something that I need to do?

Could the smog check people done something in the course of their testing that would have created this problem?

If the car is running good, I would let it go unless the check engine light comes back on.

Well I guess that what I thought was loose connection turned out to be more than that.
The misfire on cylinder #8 is back.

I have checked for the sound of the fuel injector firing and that seems good and the coil over the plug has the proper resistance readings.
I have not pulled the plug as it is not in an easy location and I didn't have the time this weekend.
I guess that I will take it into the shop and have them look at it and see what happens.

BTW, the monitors did finally clear up.

Let me know what you find.
Joe

I took it to the mechanic today and, of course, it worked fine for them. They went ahead and replaed the plug and coil. They stated that this is a common problem and this usually fixes it.

We will see if the problem comes back. There is no apparent damage or defect to either the plug or the coil assembly.

The coil appears to be good and the coil resistance was in line with the specs.

What should the resistance across the plug be? I can't get a reading on any scale up to 200k.

Could this be a problem?

There shouldn't be any resistance in a plug. At least noting you can get a reading of. Let me know if the problem comes back or if you have other questions.

Joe