When I purchased the car the front disc brakes were making awful noises which took away from the otherwise beautiful appearance of the car. They were repaired to the tune of $750; the fault was not of the car, but of the previous mechanic who failed to align the pads correctly, and wore them unevenly, causing them to heat up very rapidly and emit noise. The rotors had also been cut below their stamped minimum. Now the car stops firmly and the ABS works extremely well.
Additionally, when I purchased the car it was slowly losing coolant. The previous owner just kept topping off the coolant overflow tank and kept driving it as per the instructions of his mechanic. I did the same until I changed my oil at a regular interval of 3000 miles and noticed coolant in the oil. I promptly brought it in for service and all of the upper motor gaskets were replaced, the culprit was the intake gaskets. It seems to be a common problem with the 3100 SFI motor and my mechanic diagnosed the problem without even opening the hood of my car.
At about 117,000 miles, the air conditioner compressor began to make a rattling noise only when disengaged. I brought the car in for service and was told the only real solution was to replace the compressor. Instead of taking this route, I drenched the mechanics of the compressor clutch in WD-40 and now it operates almost silently.
This car is Chevrolet's high-luxury coupe, it is not built for racing or speed, but for someone interested in a good looking vehicle and riding comfortably. That being said, the 3100 SFI motor is very responsive from a stop, has adequate power for city driving, and has excellent power climbing hills. Unfortunately, from the factory it suffers from a large amount of flow restriction and because of this lacks the high end passing power the 3.4L DOHC can deliever. When accelerating in the 4,000 to 6,000 RPM range you can feel the motor working harder, but the car does not seem to accelerate more briskly with the added work. Replacing the stock air box and stock exhaust with high flowing models can offer a large performance improvement, and porting and polishing the throttle body, upper intake plenum, and lower intake manifold will allow the 3100 to approach and achieve the high end performance of the larger 3.4L DOHC.
Performance flaws aside, the car rides great, and has a very soft, easy feel when cruising at all, but extremely high speeds, but does not feel loose in cornering. It holds the road very well for a car of its size and weight and I was impressed with its stopping ability for a large GM W-Body vehicle once my brakes had been repaired. The ABS system works very well and had saved me from accidents under wet conditions on two occasions.
The interior is very nicely designed, the leather seats are very soft and plush, and all of the controls are at easy access. Many of my passengers complain that the doors are huge and very heavy, but I do not have a problem with them. The back seat is very large, and the large trunk pass-thru is very functional and I use it often. The Delco factory CD Player works well and produces good clear sound. I enjoy listening to it, and don't feel a need to replace it with aftermarket equipment.
Overall I am very happy with my Monte Carlo, and would strongly recommend the car to anyone considering one. I suggest that you test drive both a Z34 and an LS before you buy and decide of the added power is worth the very high maintenance costs that come with the Z34. You may be happier with an LS that has some basic modifications to free up air flow and regain the high end power.