finished my ssf3500 swap friday and put some miles on it over the weekend. last night i was in town cruising in drive (3rd) with converter locked up. i noticed when i roll on the gas i get a rattle that's very loud. i tried to duplicate the sound in od but can't get it to make any noise. i can only get itthis noise when i'm in drive. any ideas what it can be??????

 

My car made a few rattling noises when I first started it after the converter swap. I could only hear it when inside the car with the windows up though. I was like WTF because I knew I had done everything right so I just went ahead and drove it. It stopped pretty quick, then I heard it do it again later on like you described but I was in overdrive and it wasn't overly loud. I've put several hundred miles on it since then and I can't remember the last time it did it. I don't know what it was but it sounded like it was coming from around the converter. Oh well everything seems OK so I guess it's alright. Maybe someone else has a definate answer.

 

I just had a new Yank SS3600 installed on my '99 A4 and it's doing exactly what BriancWS6 described. Did anybody figure out what it was? This ****'s freakin' me out.

 

Well, mine doesn't make any weird noises at all, hasn't done it since I last posted about it. One thing that does make a little rattle, it may have been this all along but I don't know, is the freakin heat shield on the pass side just barely vibrates on my header. Only does it sometimes when I'm backing up or something real slow. I put a piece of rubber in between them and it worked til it fell out. Check that and see if it's a possibility, or maybe it'll go away like mine did. Good luck.

 

After I did my headres and ORY, something rattled for a while. I though FOR SURE it was the heat shields.

Turned out it was a slightly loose O2 sensor. As soon as I thightened it, the sound went away. This was an intermittent rattle as you describe...might want to check your O2s......sometimes it is the little metal ring on them that rattles too.

 

This is all good to know. I didn't think anything inside the tranny housing would make that kind of distinct noise. I'll bet it's the O2 sensor Someone else had a bad sensor ... said the inside of it had broken somehow. I checked all the heat shields and push on them firmly. It doesn't seem to be any of the heat shields. I'll put it up on jackstands today and look at it again.

Thanks alot for your suggestions. I'll post when I find out the root of the problem ... so maybe it will help someone else.

 

I'm Sure You Will Find It.

 

Problem SOLVED !!! It was a loose passenger side front O2 sensor. Thanks for all your help folks.

 

*ssleeper takes a bow*

 

Good catch dude!