1989-1990 Tracker, Sunrunner Distributor: Oil Leaks, Symptoms, and Replacement Timing
Your definitive guide to diagnosing and replacing the distributor in the 1989-1990 Chevrolet Tracker, Geo Tracker, and Pontiac Sunrunner, with a focus on the common oil leak and correct timing procedure.
- This distributor fits the 1.6L 8-valve engine ONLY. It will not fit later 16-valve engines.
- The most common problem is an oil leak from a hardened O-ring between the distributor housing and the engine head.
- When replacing the distributor, the engine MUST be set to Top Dead Center (TDC) for cylinder #4 (closest to firewall), not cylinder #1.
- A high-quality used OEM distributor with a new O-ring, cap, and rotor is often a better choice than a cheap new aftermarket unit.
Symptoms of a Failing Distributor
A bad distributor can cause a range of problems, from subtle to severe. If you notice any of these signs, it's time to inspect your ignition system.
Engine Performance Issues
The most common signs of a failing distributor are related to engine performance. Because the distributor is responsible for spark delivery, any issues will immediately affect how the engine runs. Symptoms include:
- Engine Misfires: You might feel a stumbling or shaking, especially when accelerating. This happens when worn components like the cap or rotor cause a weak or inconsistent spark.
- Rough Idle and Stalling: The engine may vibrate or shake at idle, and could even stall unexpectedly at a stop light.
- Difficulty Starting: A failing distributor can make it hard to start the engine. You may experience long cranking times, or the engine may crank but not start at all.
- Check Engine Light: Your vehicle's computer can detect misfires, which will trigger the check engine light.
The Common Oil Leak
One of the most frequent issues with the distributor on the 1989-1990 Tracker, Sunrunner, and their Suzuki counterparts is an oil leak from the back of the engine. This is almost always caused by a small, hardened O-ring that seals the distributor housing to the cylinder head. Over time, this rubber O-ring becomes brittle, cracks, and allows engine oil to seep out, dripping down the back of the engine and onto the transmission bellhousing. While messy, the fix is often just a new O-ring, which is very inexpensive.
Known Issues, TSBs, and Recalls
There are no recalls or Technical Service Bulletins (TSBs) from General Motors or Suzuki that specifically address distributor failure on these vehicles. Searches of the National Highway Traffic Safety Administration (NHTSA) database show recalls for the 1989-1990 Geo and Chevrolet Tracker related to seat belts and incorrect emissions labels, but none for the ignition system. The most well-documented 'known issue' is the aforementioned oil leak from the distributor housing O-ring, widely discussed in owner forums and repair videos.
Buying a Used Distributor
Since new OEM distributors have been discontinued, your main options are new aftermarket, remanufactured, or a used OEM unit. For these specific vehicles, a used OEM distributor can be an excellent, cost-effective choice, especially since the most common failure point is a simple O-ring.
What to Inspect on a Used Part:
- Check for Oil Saturation: The unit should be relatively clean. If it's caked in old, black oil, it was definitely leaking. This isn't a deal-breaker, as you should plan to replace the O-ring anyway, but it confirms the common failure.
- Inspect the Housing: Look for any cracks in the aluminum distributor body and the plastic cap.
- Examine Electrical Connectors: Ensure the connectors are not cracked, broken, or corroded. The wiring should be flexible and not brittle.
- Check the Shaft: The distributor shaft should spin freely by hand with no binding or excessive side-to-side play.
- Cap and Rotor Condition: While you should plan to replace the cap and rotor as part of the job, check their condition. Heavy corrosion or carbon tracking on the terminals can indicate a long period of neglect.
Pro Tip: Given that the primary failure is often the inexpensive O-ring, a high-quality used OEM distributor with a new O-ring, cap, and rotor is often a more reliable and durable solution than a cheap, new aftermarket unit.
Replacement Guide & Setting Timing
Replacing the distributor is a moderately difficult job for a DIYer, mainly because it requires setting the engine's ignition timing. If you are not comfortable with this process, it's best to leave it to a professional. Physical access to the distributor is relatively easy, as it's located at the back of the engine on the driver's side, mounted to the cylinder head.
Warning: There is significant conflicting information online and in some repair manuals about timing this specific 1.6L 8-valve engine. Many sources incorrectly state to time the engine to cylinder #1. For this Suzuki-based engine, you must set the engine to Top Dead Center (TDC) on the compression stroke for cylinder #4 before removing the old distributor.
Step-by-Step Overview:
- Set Engine to TDC on Cylinder #4: Rotate the crankshaft pulley until the timing marks are aligned. To confirm you are on the compression stroke for cylinder #4 (the cylinder closest to the firewall), remove the spark plug and feel for pressure building as you approach the mark.
- Mark Everything: Before removing anything, use a paint pen to mark the position of the distributor housing relative to the engine, and the position of the rotor relative to the distributor housing. Label the spark plug wires so you know where they go on the new cap.
- Remove the Old Distributor: Disconnect the negative battery terminal. Disconnect the electrical connectors and vacuum hose from the distributor. Remove the cap. Unbolt the single 12mm bolt holding the distributor to the head and pull the distributor straight out.
- Install the New Distributor: If you're fixing an oil leak, now is the time to replace the O-ring on the housing. Lubricate the new O-ring with fresh oil. Insert the new distributor, making sure the rotor is pointing to your previous mark. As you insert it, the helical gear will cause the rotor to turn slightly, so you may need to try a few times to get the final position correct.
- Set Initial Timing: Align the housing with your original marks and lightly tighten the hold-down bolt. Reinstall the cap, wires, and connectors.
- Final Timing with a Timing Light: Start the engine. With the engine warm and at idle, connect a timing light. Loosen the distributor hold-down bolt and rotate the entire distributor until the timing is set to the specification on the under-hood emissions label (typically 8 degrees BTDC). Tighten the bolt and re-check the timing.
| Part or Service | Estimated Cost |
|---|---|
| New OEM | $0 (Discontinued) |
| New Aftermarket | $90 - $150 |
| Remanufactured | $100 - $180 |
| Used OEM | $45 - $140 |
| Shop Labor | $150 - $300 |
Frequently Asked Questions (FAQ)
Is the oil leak from my distributor serious?
The leak itself is usually slow, but it should be addressed. It can make a mess of your engine and driveway, and if it gets bad enough, it could lead to low oil levels. More importantly, the oil can degrade rubber hoses and wiring harnesses it drips on. The fix is very cheap—just a new O-ring—so it's worth doing.
Why do some guides say to time the engine to cylinder #1 and others say #4?
This is a common point of confusion. Many general repair manuals use a standard procedure based on cylinder #1. However, for the Suzuki 1.6L 8-valve engine used in these vehicles, the factory procedure and the consensus among experienced owners is to time it based on cylinder #4 being at Top Dead Center on its compression stroke. Following the wrong procedure will result in the engine not starting.
Do I need to replace the whole distributor if only the cap is bad?
No. The distributor cap and rotor are considered maintenance items, like spark plugs. They wear out and are designed to be replaced separately. If you are only experiencing symptoms like misfiring under acceleration, you may only need a new cap and rotor. If you have a no-start condition or a severe oil leak from the housing, then replacing the entire assembly might be necessary.
Is a used OEM distributor better than a new aftermarket one?
Often, yes. The original OEM distributors are generally high-quality units. Their most common failure point is the external O-ring, not the internal electronics. A cheap new aftermarket distributor may use lower-quality internal components (like the ignition module or pickup coil) that can fail prematurely. A good used OEM unit with a new cap, rotor, and O-ring can be a very reliable and budget-friendly option.
Technical Specifications
OEM Part Numbers: 96062560 33100-58B10 33100-60A10
Fits 1.6L SOHC 8-Valve G16A engine. Uses a vacuum advance mechanism.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Chevrolet Tracker:
- Geo Tracker:
- Pontiac Sunrunner: