Report "I got a 98 chevy malibu that broke down and its very heavy when i try to start it.i checked the battery, replaced the starter and checked the spark plugs to make sure they were working properly. i took the park plugs out for the motor to lose compression and turn over easier and it did. i put them back in and once it got pressure again it started turning over very heavy until it just clicked. i checked the timing chain and it was off a little.put it back together and it did the same. i unhooked the exhaust thinking the catylic converter was stopped up but it still did the same. what else could it be?"