This is a bit of a tough one. The 2008-2011 era Imps shared the gutsy 2.5i SOHC motor
with the larger Leg/OB, with a reasonably tough 4EAT trans. As you know, acceleration is
strong, but fuel eco relatively poor by modern standards. Ride comfort is quite good,
however, so these can be great urban winter rats. Cleaning and resealing a rim and
balancing a tire is only $20-30. Sway bar end links break off, but are cheap to replace. I'd
take of them in the rear to reduce body roll, as well as the front to stabilize handling.
What's the problem with the exhaust? Center and rear parts are affordable...the front
much pricier. Do you have a CEL PO420 for a weak cat conv? This is the common
situation.
The big deal is of course the HGs, which are problematic for all 2.5i SOHC before 2010.
Is the #4 cyl corner leaking coolant? How badly? Is the right head leaking oil? How
badly? (Note: use 5w winter or 10w summer, NOT 0w!)
Brake jobs on your Imp are easy and fairly cheap, as full rotor/pad sets can be bought
online well under $100/axle and can be installed in less than an hour.
HOWEVER, if the HGs are bleeding badly you must remove the motor, send the heads
out to a machine shop, re-gasketing them nicely, swapping the t-belt and pulleys (but not
the waterpump nor t-stat), and carefully purging the cooling system. Cost for all this is in
the $1.4-1.7k range, and MAY bot be prudent, especially if you have a pricey front
exhaust job, or maybe BOTH f & r brakes needed. I'd have to see your chariot in order to
predict the death curve more accurately. Note that modern Imp/CT/Fors suffer from many
more QA issues than before, and are anemic compared to your beefy 2008, so I generally
suggest that early Imp owners get a modern (2015+) OB, or if that much cargo space isn't
required, the better value Legacy Sedan. (Disclaimer: I sell these.)
Good luck. Ern TSG/B