Hi all, I've got a 1994 EF GLI that has a funny little problem which I have yet to find the source of. Between 1500-2500 rpm I have a rattle in the engine around the fourth and fifth cylinder area. I've had a few people listen to it and all but one believe it's a detonation sound, the other mechanic said it's the motor (hunting for a big job I think). It started to miss really badly so I replaced plugs (which were rooted), leads and coil pack. I ran great but still rattled. I've replaced liters. I put it on a scanner and it brought up cam sensor and knock sensor codes. I checked cam sensor position (wrong) and reset it correctly and replaced the knock sensor. Still rattles. Plugs wore out in three months, which suggests to me that it is running lean, but it chuggs the juice. My next step is the renew the injectors or a new ECU. PLEASE HELP!!!!!

you didn't need to replace the knock sensor.

the knock sensor code is only telling you that the knock duty is out of range.
Normal for the complaint you have. it is picking the rattle and translating it as knock.

befor you go replacing other stuff get the car on a dyno and have the air/fuel ratio checked.

check the ignition timming with a timming light to make sure it's all good.
make sure you have the right heat range plugs in the engine.

Plugs are stock NGK ones, BPR5EY-11. Any ideas on how to check timing correctly? I had a timing light on it the other day and it seems to be really advanced at idle, but I don't know if I had to put it in a mode like the EA-ED models. Any help?

Also replaced air pipe to MAP Sensor, intake gasket and checked all vacuum pipes that could throw out air/fuel readings.

does it do it hot and cold?

we had a 97 vs senator in at work today and it had the same problem as you describe. it would idle fine but when you placed the engine under load it would mae a rattle. we put it on the hoist and had a listen. it turned out to be that the flywheel cover was slighly bent and touching the flywheel. this may or may not solve your problem but its worth checking

hope this helps