Why is this happening?
Several things can cause torque converter lockup problems:
* Low Transmission Fluid: This is the *easiest and cheapest* thing to check first. Low fluid leads to overheating and can damage the lockup clutch. Check the fluid level *while the engine is running* (consult your owner's manual for the proper procedure). If low, top it off with the correct type of transmission fluid (Dexron III or equivalent for a 1989, check your owner's manual). If the level is low and the fluid is dark brown or burnt smelling, you likely have a bigger issue.
* Faulty Torque Converter Lockup Solenoid: This is a relatively inexpensive part and fairly accessible. The solenoid electrically controls the lockup clutch. A failing solenoid can prevent lockup or cause intermittent lockup. Replacing this is a moderate repair.
* Worn Torque Converter Clutch: This is a more serious and costly repair. The clutch itself within the torque converter might be worn out or damaged. It may require removing the transmission to replace the converter.
* Transmission Control Module (TCM) Problems: The TCM is the "brain" controlling the transmission. A faulty TCM can prevent the lockup from engaging correctly. Testing this requires specialized tools and often a replacement is necessary. This is a more complex repair.
* Wiring Issues: Check the wiring harness leading to the torque converter lockup solenoid for any broken wires, corrosion, or loose connections.
Easiest Repair First:
1. Check and Top Off Transmission Fluid: This is the absolute first step. It's the simplest and cheapest check, and often solves the problem.
2. Inspect Wiring: Look for obvious damage to the wiring harness related to the lockup solenoid.
Moderate Repairs (if the easy checks fail):
3. Replace the Torque Converter Lockup Solenoid: This is usually easier and cheaper than tackling the torque converter itself. You'll need to access the transmission and locate the solenoid (consult a repair manual for your specific vehicle).
More Difficult Repairs (require specialized tools and/or transmission removal):
4. Torque Converter Replacement: This is involved, and you likely need professional help unless you have considerable mechanical experience and the right tools.
5. TCM Replacement/Repair: Requires diagnostics and often professional help.
Before you start any repairs:
* Consult a Repair Manual: Get a repair manual specifically for your 1989 Chevrolet Corsica. This will provide detailed instructions, diagrams, and torque specifications.
* Gather the Right Tools: You'll need basic tools like wrenches, sockets, screwdrivers, and possibly a transmission jack (depending on the repair).
* Safety First: Always disconnect the battery's negative terminal before working on any electrical components or near the transmission.
In short: Start with the simplest checks (fluid level and wiring). If those don't solve the issue, a new lockup solenoid is often the next step before you start considering major transmission work. If you're not comfortable working on your transmission, it's best to take your car to a qualified mechanic. They can diagnose the problem accurately and perform the necessary repairs.
