Spark Plug Earthquake

sentra
sparkplugs

#1

I installed BKR5ES-11 sparkplugs into a Nissan Sentra 98 GXE. It is a 2.0 Liter. After installing the sparkplugs (not using a torque wrench) the car shook quite a bit. The gap stated for us by the guy at Murray’s was .044. However, in the manual, it says to get BKR5E spark plugs - not BKR5ES-11. In addition, the manual says a gap of .031 to .035 is required.



I’m wondering if the car is shaking like Mt. Saint Helens because I didn’t torque the plugs correctly by hand (I used the hand tight on the back) or if the spark plugs and gaps that Murrays recommended are not going to work.


#2

correction: 1.6 liter, thanks, Sharon


#3

I found an NGK code symbol page: http://www.spark-plugs.co.uk/pages/technical/ngk_symbol_code.htm

The plug is the right one, but the gap is off. Re-gap the plug to what the manual says, and try again. I’ve rarely gotten copper-core plugs that were set to the correct gap from the parts store.


#4

Its the gaps. The difference in the plugs is the electrode shape, the ones you bought is designed for a .044 gap, the ones listed in the book are designed for the .032 gap.

Plugs can be put in without a torque wrench, but it helps. In the days of cast iron, you could just muscle them in, as long as you didn’t get carried away. With aluminum heads, you have to be careful not to strip the threads. Generally if you are using a 3/8 drive ratchet, you won’t over torque them, if you are reasonable. Another guide is a 1/2 to 3/4 turn from finger tight if it has a gasket, 1/8th turn if not.


#5

Not to offend, but are you sure you got the wires in the right order. I have changed plugs on my cars, never had a torque wrench and one of the first cars the plugs had almost desolved and were still running without major misfire. Granted a wrong gap causes issues, but I think yours are extreme.


#6

As mentioned, I would verify the plug wire order is correct first. After that, it’s possible that a plug wire(s) could have been ruined by the simple act of removing and installing them; especially if they did not come off very easily.