So my fiance and I just purchased a 1999 Ford Escort SE (4 door). Drove it home, seemed fine. Was told it just needed some TLC and would be good to go. I don’t know too much about cars (Besides the basics and what certain things could mean). So, got it home, was checking it out. Revved the engine, and when it decelerated down there was a loud knock that sounds to be coming from underneath the car, I looked underneath and all that I can see which it could be (from the general location of the noise) is the engine or the pipes. So, is this a rod issue? Could it be a loose flywheel? I’m hoping we did not just buy a car to have to go scrap it to gain back some of our losses. Being as times are tough and money is tight.
A single knock or consecutive knocks?
EK Hammer, it’s a constant knocking until it reaches Idle. Only does it when the rpms are coming down. Doesn’t do it when you’re driving normally. Only when you rev the engine.
Actually maybe not until it reaches idle. Maybe a little bit before. My dad was just checking out my purchase. And when I mean rev it I don’t mean just give it a little gas, I mean the type of rev that unless you were checking out the engine you’d sound like you were trying to show off.
It does sound like a rod knock. Easy to diagnose if you can get the pan off (here’s a Nissan):
I agree. Sounds like symptoms of a rod knock. Does the dash have an oil pressure gauge or an idiot light? If it has a gauge, what’s the oil pressure and does it fluctuate a lot?
I’d have someone check the motor mounts too–broken motor mounts can cause all sorts of weird sounds that mimic serious engine problems.