[redracer]

Anyone have thoughts on what could cause this light to go on with my 2000 MT Insight??

My problems started after having spark plugs installed at non-Honda shop.. mpg cut in half, sluggish after installation. I had Honda look at it. They said wrong plugs were installed, but no codes showed up when Honda tested it and could not find anything wrong. The shop then installed Honda, "B" plugs at no cost, but no significant improvement. Today, weeks later, the Malfunction/Check Engine light came on (steady).
It may be unrelated, but yesterday a storm resulted in a 4 ft tree limb actually getting caught in the underside of the car when I drove over it, had to yank it hard to remove.

Is there anything the tree limb getting caught underneath the car could have done to cause this light to come on?
I've read that misfiring can cause the CATs to get clogged and trigger this indicator- if that is the case, would the converters have to be replaced?

I am taking it again to Honda to pull the diagnostic codes, but given their limited knowledge of our special cars would appreciate any feedback from members here to help them.
It seems too coincidental that problems started after the plugs were installed.

 

[Eli]

We can't tell you anything without knowing the codes. It would be a complete shot in the dark; could be anything from a loose gas cap to your engine being on the verge of implosion.

Sorry to be of little comfort.

 

[gilbertguy]

First rule of trouble shooting... what did you do to it!

So, with that said your problem started when the plugs were installed so that is where I would start. There is a posibility that the connection of the wiring harness to the coil pack could have been damaged, unplug each connection and inspect it for pins backing out or some kind of damage there. Next I'd remove the coil packs and pull the plugs and look at them, see if they look clean or if they are gummed up with fuel or gunk. If one of the coil packs is bad or not getting a signal then the plug may not be firing which will kill your power and burn more gas. Let us know how the connections and plugs look.

Now as for the branch you very well may have damaged something under the car, there are wiring harnesses that could be damaged. You need to get the car up in the air and do a good inspection under the car, pay close attention to the O2 sensors around the exhaust system and associated wiring. You won't know what could be wrong until it is looked at, I'm not sure the two things are related.

The engine in the car is still an (ICE) Internal Cumbution Engine and works basically like all others out there in the world. Let us know what you find.