How to tune "Buffer Get" offender

Question

QUESTION: How to tune following sql
SELECT *
FROM trans
WHERE accountid = NVL (NULL, accountid)
AND transtypeid = 171
AND NVL (description, '-1') = NVL ('Card Activation Fee ', '-1')
AND ABS (transamt) = ABS (9.95)
AND accountid <> 7689966
AND postdate BETWEEN ( TO_DATE ('03/14/2006 00:17:43',
'mm/dd/yyyy hh24:mi:ss'
- .00011574
AND ( TO_DATE ('03/14/2006 00:17:53',
'mm/dd/yyyy hh24:mi:ss'
+ .00011574
DETAILS:
Statspack has shown this piece of SQL as the largest contender for "Buffer Gets" chewing up 513.28 seconds of CPU time out of 3,475 (See Top 5 Timed Events below)
However, when I run the sql statement by itself in TOAD, it takes 90ms to complete and has a cost of 202 (See plan below). TRANS table has over 18m rows.
Operation     Object Name     Rows     Bytes     Cost     Object Node     In/Out     PStart     PStop
SELECT STATEMENT Optimizer Mode=CHOOSE          1           202                     
TABLE ACCESS BY INDEX ROWID     SVOLTP.TRANS     1      65      202                     
INDEX RANGE SCAN     SVOLTP.TRANS_POSTDATE_NIDX     1 K          7                     
Top 5 Timed Events
~~~~~~~~~~~~~~~~~~ % Total
Event Waits Time (s) Ela Time
CPU time 3,475 49.99
db file sequential read 1,340,884 3,197 45.99
db file scattered read 180,048 70 1.01
db file parallel write 3,983 49 .70
log file sync 20,593 43 .63

Answer 1

here is the actual statement taken from the package:
select transid
into lFromTransID
from trans
where accountid = nvl(lacctid, accountid)
and transtypeid = lToTrans.transtypeid
and nvl(description, '-1') = nvl(lToTrans.description, '-1')
and abs(transamt) = abs(lToTrans.transamt)
and accountid <> lToTrans.accountid
-- Transactions must be posted within 10 seconds of each other
and postdate between (lToTrans.postdate - .00011574) and (lToTrans.postdate + .00011574);