1998 Mazda Protege

1998 Mazda Protege 4 cyl Front Wheel Drive Automatic 149000 miles

my car has a knocking and a friend told me its cause a piston at one point didnt have any compression so he told me to use lucas to see if it would remove the knocking. What do you guys thing it is?
September 21, 2010.

Lucas isn't going to fix your engine knock. If you have too low of compression you won't get a knock you will get a dead hole meaning that cylinder won't run. You would have to figure out which cylinder was knocking and find out if it was a spun rod bearing or what was causing it and fix it.

Sep 21, 2010.