[mike sevel]

'08 328i 90k MILES. REPLACED PLUGS WITH NGK PLZRF6A-11S 5987
WITH A 44MM GAP.

Start car, runs rough, service engine light comes on!

What did I do wrong???

Pls advise.
Thanx, Mikey

[Brandoch]

Originally Posted by mike sevel

'08 328i 90k MILES. REPLACED PLUGS WITH NGK PLZRF6A-11S 5987
WITH A 44MM GAP.

Start car, runs rough, service engine light comes on!

What did I do wrong???

Pls advise.
Thanx, Mikey

Check for codes to see what it is angry about.

[Mike K]

When I put new plugs in my 2011 328i two coils failed so I replaced those too. Moving the bad coils moved the error code too. At about 100k miles.

[NZE90]

Maybe you bought fake chinese NGK plugs?

[GoRomeo]

Originally Posted by mike sevel

'08 328i 90k MILES. REPLACED PLUGS WITH NGK PLZRF6A-11S 5987
WITH A 44MM GAP.

Start car, runs rough, service engine light comes on!

What did I do wrong???

Pls advise.
Thanx, Mikey

Make sure you plugged everything correctly. Sometimes oil drilps into the plugs hole and the car will run roughly intil the oil is burned off. Once this happens the car should start running smoothly again. You may also see white smoke coming out the exhaust for only a minute or two.

[mike sevel]

Update:
Car was running rough after new plugs added. Service engine light on dash.
Used basic analyzer for a code that I referenced on the net and it was a failure of #5 coil. Car was running fine prior to new plugs.
I had replaced the coils 5 years ago and it died by coincidence. Had an old coil left over and replaced it for #5 and car is running fine now.
Mikey