Check trouble codes - see the sticky at the top of the 4.x engine section for instructions and what the codes mean. The one you need to especially watch for is E39, VCC engagement problem. That's the first sign of a failing transmission.
An '88 is a 4.5 engine car - very reliable and durable engine if it's been well maintained. Get a service history if one is available.
Check for milky or lumpy oil on the dipstick, or oil slicks in the coolant. Both are signs of head or intake gasket issues. If the coolant has been changed according to the GM recommendation, and the sealant used, the 4.5 is good to go for 250k+. Other expensive items are struts, self-leveling rear suspension, A/C.
An '88 is a 4.5 engine car - very reliable and durable engine if it's been well maintained. Get a service history if one is available.
Check for milky or lumpy oil on the dipstick, or oil slicks in the coolant. Both are signs of head or intake gasket issues. If the coolant has been changed according to the GM recommendation, and the sealant used, the 4.5 is good to go for 250k+. Other expensive items are struts, self-leveling rear suspension, A/C.
