Does anyone know how to reset the check engine light in the H3? It needed the spark plugs changed and we did that but the engine light is still on...help please

 

Try disconnecting the (-) battery cable, then step on the brake/press horn a few times (the horn should not beep). This should drain all of power. Then hook the battery back up and see if it cleared it.
Disclaimer: This will wipe out the computer's stored memory functions so it will need to re-learn your driving style. I did this when my 4wd light came on after changing my radio, and it did the trick. I also used this trick on my Mustang Gt whenever I would bolt on a power adder (throttle body, intake, plenum, etc.).

-Tim

 

did you replace the plugs yourself and not have access to a code reader to clear it? or did you have them done at a dealer. If i am not mistaken if you do not clear the code it will not go off until there are a certain amount of "good" readings telling the computer the truck is now operating correctly. Then it should go off. For instance, the truck was probably misfiring after a few consecutive trips kicking the light on, if not cleared it will stay on until there are consecutive trips without a misfire.
How does it run by the way and what mileage did you need to change them at?

 

How did you know the spark plugs needed changing? What code was set for the light to come on? Any repair shop can put their scanner on the vehicle and clear the light, if the problem was fixed. mthoodh3 is correct about the check engine light will reset once the ECM sees a number of certain driving conditions are met and no faults detected. Disconnecting the battery is not a guarantee the computer will reset.

 

Hi all,

I have the H3 2007 with 44000 miles.
From the beginning i have the engine light that lights up and goes off again.
Took it to the garage and they told me that is was normal because i run on gas.
They hooked it on the computer and there they saw it was a missfire on cilinder 5.
They erased the code and the light was gone.
A few miles later it came back on.
They say it is a well known problem, because running on gas needs 3000v more and when the engine gets less, the missfire code takes place.
The told me to change the spark pluggs and maybe that would solve the problem.
I ordered them and am still waiting for them to arrive.
But now i did something else!
I bought an OBD 2 scanner ( ebay 25us) and scanned my car myself.
It found 1 problem. I simply erased it. And......
The light is off! It is still off and i drove already 110 miles with no enoying lights on.
And, maybe i imagening it, but it seems i have more power. It accellerates better than before.
So, happy with my tool from ebay and no more garage costs to read/erase codes or turn off the engine check lights.

K.

 

Does anyone have a service manual that you could email me, I need to change spark plugs, running really rough, but I want to do it the most straightforward and efficient way not my usual trial & error when I disconnect a number of parts I didn't need to. Thanks in advance, fields2you@gmail.com 2006 H3 fully loaded (not me the hummer)

 

PM "2wheelmonster"......he has them

 

Even old stuff that is wrong still needs a reply.

GM didn't build any Mustangs.

The H3 PCM stores the last 300 ignition cycles (that is flash based, power on or off has no effect upon it). Disconnecting the battery, stepping on the brake, touching the + & - terminals together, dancing in circles doing a voodoo chant, all do nothing to those 300 cycles.

The only way to get rid of them is to flash the PCM with another tune and start fresh.

 

Remove the intake from TB to Air Filter Box, remove the single bolt holding each of the five coil on plug packs in place, pull up the coil pack, remove plug, check gap on new plug, replace each, and reverse.

If you need a manual to do plugs on an I5, maybe ??? you should have someone help??? On a scale of 1-10 (10 most difficult with specialty tools), plugs on an I5 are about a 1.1 or so.

How many miles on your 3?

Welcome to the forums.

 

Doc:

75K, thanks for the response but you may need to take a Dale Carnegie "Win Friends & Influence People" course, there is a great amount of knowledge we all have in certain areas, I'm sure you would have trouble with performing even the basics in what I do for a living and probably visa versa, difference is, I wouldn't tell you you might need help just because you had to ask for input on something I think is simple to do and it wasn't so obvious to you. I've regreted NOT asking the stupid question when doing car repair in the past, I like to avoid making the same mistake over 100 times is all. LOL

Having said that I do appreciate the response, not everybody bothers!