New plugs on the M60

[Traian]

I gave the ol' girl (actually I rather like to think of her as a young maiden, but 'ol girl sounds more loving) some new plugs, as I had a set lying around. Before she ran Bosch Platinum +4s (apparenly), new ones that went in were Bosch coppers. Car runs basically the same, though I did notice startups are a little easier and she idles a tad lower.

Sooooo, to cap the ramblings, why does my car still have a shudder at idle? I know I kinda popped that one out at y'all. It's hardly noticeable really, in fact I only really notice that it was there when it stops and the car starts idling smoothly again. The tach needle stays solid, it's only a butt-ometer reading, but still, I'd rather like it to go away. I don't really know how else to describe it, it's really just the faintest shake, as if I were running a hotter cam, and I doubt anyone else riding in the car has noticed it. Ahh and to spice the pot, it seems to go away when the car is placed in Neutral, only Park brings it up.

Go figure...

[Traian]

*crickets chirping*

[632 Regal]

dude the V8s have a slightly cam on type of idle, its to do with the real low idle forced by the ecm, ideally if these were carburetored engines they would idle moe likely at around 900-1000rpms. Some roughness is normal as long as it itnt a definite miss on one cylinder.

[winfred]

try shooting a little carb cleaner under the intake front and rear when idling cold and hot and see if the idle changes, intake leaks are common on v8s

[Traian]

632 Regal: My idea too, but at some points it smooths itself out, and then the little shake returns.

winfred: Also a possible, but I did that a couple of months ago when I had a real bad idle shudder with CEL and the whole nine yards, and ended up replacing one of the intake gaskets (actually a shop did that for me).

[winfred]

did they do the seals on the front and rear covers too, most people skip the one on the front and it cracks on the bottom, plus that pcv plate on the rear can **** up and suck air, a can of carb cleaner is cheep and quick, some motors are a bitch to find the leak on that's why i suggested checking it cold and hot, some leak hot some leak cold and then seal up

winfred: Also a possible, but I did that a couple of months ago when I had a real bad idle shudder with CEL and the whole nine yards, and ended up replacing one of the intake gaskets (actually a shop did that for me).

[Beez540]

I actually really like it. expecially with no resonator... the slight lope at idle on a V8 sounds so soothing coming out the tail pipes...

[Super90]

All true stuff. One other thing to check is that the idle control valve is clean. It's that little cylinder that sits sideways on top of the throttle body. The air intake feeds it too. That's what that second hose clamp is attached to. Just pull the electrical connector, take the little rubber hold-down strap off and it's free to inspect. I just spray some carb cleaner or intake cleaner in there and make sure that everything moves freely. You should be able to twist it quickly and have it "click-clack" a bit. Don't get overzealous though. Then, put it all back together.

Even if that wasn't the problem, it's good M60 maintenance !!

YMMV,

R.