1997 caravan oil light keeps comming on

i have a 1997 grand caravan with the v6 engine we've had a slow oil
leak for a while know, put in about a quart every few weeks, but
recently the oil light has begun comming on when the rpm's in the
engine drop. it only does this when the engine is warm (say after
10-15 minutes of driving) then whenever the rpm's drop (slowing down,
parking) the oil light will come on, and when the car is shifted back
into park sometimes that shuts off the light. i have also noticed that
accelerating also shuts off the oil light. I have dipped the engine
and it seems to be over full (oil about 3 inches above the full mark on
the dipstick.) is this car safe to drive? any ideas on what may be
happening?

puzzled

 

It is almost certainly simply in need of a new oil pressure switch -
very common. Usually due to an internal leak in the switch throwing off
its calibrated trip point off, it trips at a pressure slightly higher
than what it is supposed to - the lowest running pressure it will see is
at idle in gear. When you pop it into neutral or park, the engine idle
speed increases just enough to open the switch and turn the light off.

Replace the pressure switch. But for peace of mind, you might also have
the pressure checked.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

 

Hi...

Not a mechanic, furthest thing from it - an old retired electrical guy,
so take whatever I say with a grain of salt...

In this case just wondering if no one else noticed the dipstick oil
level being three inches over the full mark.

Take care.

Ken

 

Good catch, Ken - I skipped right over that part. However, if that were
going to cause problems, it would be in high speed engine operation
(whipping/aeration). Perhaps someone kept adding oil thinking
incorrectly that that would fix a low oil pressure situation (sometimes
people equate *level* of oil with oil *pressure*). But I think probably
in this case, the over-fill of oil is unrelated to the oil light coming
on only at idle in gear (I could of couse be wrong).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')