ISC o-ring trick

[MaddBaggins]

Had the usual start up rattle and I thought I would try this trick and see what happens
http://www.lcool.org/technical/80_series/fast_idle/fast_idle.html
I have greatly reduced my rattle by using a thicker oil M1 15w-50.
My start up rpms(cold start) would go up to 1800 then down to 1400 and hold there for a while then fade down as the truck warmed up
So I did the o-ring trick with 2 o-rings. Start up was good about 1000 rpms then down to about 500 rpms. Later while driving around I noticed my rpms at a stop light were down to about 200 and a couple of times I thought it was gonna stall.
Got home and opened it up and removed 1 o-ring. Now, this morning, I started up at 1600 rpms them down to about 1300. This afternoon, however, will be the tell. I always get start up rattle after work.
Anyone else do this and what were your results. Thanks

 

[Bear80]

My dad did that mod for his '95, so far after 4 years he just copes with the low idle. Does feel like it's about to die but here in TX the a/c keeps the idle up.

 

[MaddBaggins]

Well, on start up after work today, I almost heard a very faint rattle. I think this o-ring trick and the thicker oil might just do it. I am going to go with 1 o-ring for a while and moniter things. If I need to I will try 2 o-rings again.
Anybody else try this besides me and Bear80's dad??

 

[cruiserman]

The o-rings didn't work for me. I put a thin washer on there, and it's worked over the last part of the summer. 1400RPM cold start and quick drop compared with 1800+ before.

 

[MaddBaggins]

Sounds like we're pretty close on results. Washer, huh?! Cool.
Since I put in thicker oil, My rattle went away in my driveway. I have a slight incline to the house and I always back it in, so in the a.m. I no longer get rattle. I was still getting a fair bit of rattle in the afternoon at work-flat parking lot-until I tried this.