"lawnmowering"

My 1993 Nissan Altima has been idling like a Harley Davidson for a long time now (years). I made sure it’s getting fire to all cylinders. It “catches” at about 15 mph and then has all the zip the car should have. Even though it’s one of those symptoms that sounds like the car is going to take a dump at any moment, I’ve never gotten serious about it because the thing always passes smog and just never has a problem. It’s the proverbial E-bunny. Any ideas?

Thanks,

blaerby

Vacuum leak at the intake manifold. It makes one cylinder too lean so it misfires. As you pick up speed, the vacuum leak has less effect.