Rattle at idle in gear

[aberg83]

So I got my shifting working thanks to some help in another thread. Might need a slight adjustment since it still grinds a little going into reverse.

My biggest issue now is that when the car is in gear, idle rpm drops quite a bit and was initially stalling at stops. I increased the idle to around 950rpm while in gear. It is up over 1000 in neutral. When in gear, the engine doesn't sound healthy. There is some rattling going on. I suspected the torque converter because the sound is gone when in neutral. I thought maybe a flex plate bolt was loose so I checked all 4 and they are tight.

Any ideas?

[aberg83]

Ok, figured it out. I had recently swapped to a ribbed style alternator belt. Put the smooth one back on and the noise is gone. It may have been the wrong size and was too loose or too tight. Either way, all is well now.

[sb001]

Good to hear- are you now able to reset the idle speed where it is supposed to be? (About 950 at idle in neutral, usually drops to around 750-800 or so when put in gear.)

[aberg83]

Turns out I had a bad intake leak at one of the manifold crush rings. I had some other reasons to pull the motor so its out now for some work.

[68autobug]

YES, I find that VW engines really hate an air leak.... more than any other engine.... or maybe because there are more ways to get a leak??
great to see that you found the problem....