1996 GMC Sonoma Problems
RepairPal has identified the most common problems with the 1996 GMC Sonoma based on complaints from actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.
The distributor may develop internal faults. This can cause a rough running engine or stalling condition and the Check Engine Light may or may not illuminate. The distributor should be overhauled or replaced to correct this concern.
The heater core under the right side of the dashboard may leak engine coolant which can puddle on the passenger front floor. The loss of coolant may cause an engine overheating condition. Our technicians tell us that removal of the dash board is necessary to replace the heater on these vehicles.
The headlight switch used on the GMC Sonoma is known to fail through normal operation. Since the headlight switch is also integrated into the interior lights, a malfunctioning switch can cause issues with interior lights as well.
- Symptoms of a failed headlight switch include:
- Headlights and taillights failing to turn on or off
- Interior lights flicker, or fail to turn on or off
- Gauge cluster lighting off or flickering with headlights on
- Parking light malfunctions
This issue is well known with General Motors Trucks and SUVs, and is solved by testing and, if needed, replacing the headlight/dimmer switch. Bad grounding wires at the tail-lights, and dirty/corroded tow package wires can also lead to some of these issues.
A fluid leak may develop from the transmission output shaft seal. This leak may cause the transmission mount to become oil soaked and require replacement of the mount along with the leak repair.
Vehicles equipped whit a 4 speed automatic transmission may develop a harsh 1-2 shift and/or illumination of the Check Engine Light with code P1870 stored. This can be caused by wear of the bore for the TCC isolator and regulator valves in the valve body. This condition does not commonly occur until the transmission reaches normal operating temperature. If the valve body is worn, replacement will be necessary to correct this concern.
A Loose or worn gas cap may cause Check Engine Light to illuminate.
The serpentine belt tensioner can fail; it may become noisy and/or the belt may jump off. Replacement of the failed tensioner will be necessary.
A door window may move slowly or stop in mid travel due to a failing power window motor. The affected window may start working again after the motor cools off. Replacing the faulty window motor will commonly correct this concern.
The intake manifold gasket may develop and external engine oil or coolant leak. In some cases, an internal coolant leak may occur causing coolant to mix with the engine oil. Running the engine with a coolant/oil mix may result in engine damage. Replacing the intake manifold gasket should correct this issue.