Even More Questions

[Lundy, Andrew]

>Recently, after changing the oil and filter,  the car began to
>exhibit a rather loud engine knock at start-up.  I know this is fairly
>common on these I-5 engines with high mileage, but it seemed to have gotten
>worse after the oil change.  Are the valves and lifters the same as a 4000Q
>hydraulic, not adjustable?

If your knocking could also be described as a "ticking" then you are getting
lifter noise.  I would venture to guess that you changed your oil to
conventional oil (instead of synthetic, i.e..Mobil 1).  With the high
mileage engines you will normally get engine "tick" with conventional oil,
usually synthetic will reduce it the tick, but not always!!

Yes, they are hydraulic lifters.  Knock sensors are for sensing detonation,
not lifters with lack of lubrication.

HTH!!
---
Andrew Lundy
90 80q
99 A6q