mikemareen

it's been about 4,000 miles ago since I did my major service consisting of spark plugs, timing belt, water pump, etc.

now my car has a slight rough idle when I come to full stop at red lights / parked while engine on. It seems to be a little less noticeable when my air condition is ON.

as u all know the ls430, we are used to zero idle while at stop while engine, so to feel anything at idle is a big deal.

any thoughts ? my coworker thinks it's the spark plug wires. I dunno.

Atl

I assume you mean the 90K service, and at that milage, I would say change the engine mounts. I doubt the spark plug wires as the coils are directly over the plugs. Be prepared for the bill though, aint cheap but what is another $900.00?? Pocket change!

campisi

Is you gas mileage affected negatively? Is the car's power down at all? To me the most likely thing is that there's a vacuum leak somewhere. Not likely to be engine mounts unless the car was driven HARD.

mikemareen

gas mileage the same, no power loss.

where would the vacuum leak be ?

Rice

I'd open up the plastic cover and look at all the fittings and connectors. Vacum leaks are a biatch to find. If you'll find some shiny fitting that looks like something was there before and not there now, consider yourself lucky.
Otherwise, go back to the mechanic and ask to double check everything that was disconnected. Chances are, he'll tell you to f/off, but it's worth a try.

socal3

iTrader: (2)

I have to agree with Rice take it back to the mechanic as soon as posible so time isn't an issue.