So I just bought a 2003 AP1 with around 90,000 miles. There is some sort of knocking noise that comes after driving the car for a while (30mins). It doesnt matter if its driven hard, or driven very conservatively, it will still make the noise half the time. I dont believe it is the TCT because it doesnt make the noise at idle, instead it makes it around 2,500-2,900 rpm range. It comes and goes and like I said there are some days where it just doesnt happen all together. I have a V2 AEM CAI, adn test pipe installed. The car is throwing an ecl, codes p0410 & p0128. The car shakes at idle but I believe its due to the faulty motor mounts. Any ideas n what could be causing the knocking noise?

 

Motor mounts can vibrate at certain rpm.

Get the mounts check and replaced, fix the CEL.

Check your oil religiously

Sort out the idle vibration (might be due to vacuum)

Report back after you've done the above

 

P0128 Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
P0410 Secondary Air Injection System Malfunction

 

I replaced the mounts and now everything is working properly, no shaking, knocking etc. Thanks for the replies guys!