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Alex, ASE Master Technician
Category: Car
Satisfied Customers: 1158
Experience:  ASE Certified Master Technician, L1 Advanced Level Specialist
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A slite miss when stoped and idling__it was time..spark plug..AC

Customer Question

bought a use 08 avalanche about six months ago__we have put about 4000 mi. on it.__i have notesed a slite miss when stoped and idling__it was time to change the oil the was about a qt. low__while changing the oil i pulled number 1 spark plug it was a MotorCraft and fouled and then i pulled all the rest and they all AC and looKed good
Submitted: 5 years ago.
Category: Car
Expert:  Tim's Auto Repair replied 5 years ago.


does the engine light come on?if so,can you give me the computer codes?

please tell me what you mean about the plugs

tell me all you can


Customer: replied 5 years ago.

The plugs in a GM should be AC brand but in the #1 hole it had a MoterCraft plug in it.

that plug was oil fowled with oil it would hit most of the time you could feel it at stop lights idiling

i havent pulled any codes

i put a new set in and it is running good now but i know it's only a matter of time and it will fowl out again.

i was just wornding if that would be something that wornity would take care of.

Expert:  Tim's Auto Repair replied 5 years ago.

how many miles is on it?

has it been using oil?

Customer: replied 5 years ago.


I just found it low this week

Expert:  Tim's Auto Repair replied 5 years ago.


i will opt out,,someone will be with you to help you with this



Expert:  Alex replied 5 years ago.
Hello. My name is Alex and I'll be assisting you with your question.

Are you concerned about the oil entering the spark plug well? That the oil will foul the new plugs?
Customer: replied 5 years ago.

I know the oil is going to fowl out the new plug.

Do you think it is the valve guide or rings in the number one hole?

and what ever it is should it be under woranty

Expert:  Alex replied 5 years ago.
The oil is getting into the spark plug holes through leaking valve cover tube seals. This means the valve cover gaskets and tube seals need to be replaced. The gaskets and tube seals will usually come in a kit together. This will most likely not be covered under warranty.