Cadillac Seville / Cadillac Eldorado Forum Discussion, 99 STS - end of the road? in Past Cadillac Vehicle Discussion; Just recently I getting all the classic Northstar signs of the headgasket letting go, random temperature rise, occasionally near the ...
Just recently I getting all the classic Northstar signs of the headgasket letting go, random temperature rise, occasionally near the red mark (enough that the A/C was shutdown), seems to happens when the car is under more load, coolant disappearing now and again, and I think I can small exhaust fumes in the surge tank, and...the block test came back positive, the blue dye turn very slightly green.
The car has done 179,000 miles, but it still drives very well, but if driven hard in the hot OK weather (100F outside) the temp will rise to the 2nd marker pass middle pretty much every time now, didn't do this few months back.
The odd thing, and I'm curious, I bought the car with about 3 years ago with 142,000 miles on it, from friend, and it has always had a slight oil drip/leak (he gave full disclosure on this fact)and told me it needs a quart of oil about once a month to top it up, and sure enough that what I've been doing, but, since this possible head gasket issue started (around 3 weeks now) the oil leak/drip has completely stopped...why would this be?
I'm coming to the conclusion that it might be the end of the road for my caddy, at that mileage, and my location, (nobody near me does the head gasket repair/mod) it doesn't seem to make much sense in having the expensive repair done, the car also has minor hail damage, but other than that, and the head issue, the car is in good shape.
Year 2009 - 2010 - Replaced air suspension compressor and filter
Year 2011 (approx mileage 152k) - Replaced rear right passenger door power window motor/lifter unit
Year 2012 (approx mileage 158k) - Replaced coil packs, plug wires, air filter, idle air control valve, MAP sensor, TPS
Year 2013 (approx mileage 170k) - Replaced surge tank, surge tank cap, radiator, top and bottom radiator hoses, rear struts, front & rear brake pads, 2 HVAC vent actuators, small power steering hose
Always had Castrol Full Synthetic 10/30 and filter change when indicated by oil life monitor.
My 2000 Seville was having temp spikes and the belt / pully to the water pump had gone bad. It is on the right side of the engine on top (visible without removing anything under a black guard). It might not be as bad as you think.